Pregnancy: Diagnosis, Physiology, and Care

Overview

Definition

Pregnancy is defined as the time period between fertilization Fertilization To undergo fertilization, the sperm enters the uterus, travels towards the ampulla of the fallopian tube, and encounters the oocyte. The zona pellucida (the outer layer of the oocyte) deteriorates along with the zygote, which travels towards the uterus and eventually forms a blastocyst, allowing for implantation to occur. Fertilization and First Week of an oocyte and delivery of a fetus approximately 9 months later.

Terminology

• Gravidity: the number of times a woman has been pregnant
• Parity: 
  • The total number of deliveries
  • More specifically, the total number of pregnancies reaching the age of viability regardless of the outcome (live birth, stillborn, cesarean delivery Cesarean Delivery Cesarean delivery (CD) is the operative delivery of ≥ 1 infants through a surgical incision in the maternal abdomen and uterus. Cesarean deliveries may be indicated for a number of either maternal or fetal reasons, most commonly including fetal intolerance to labor, arrest of labor, a history of prior uterine surgery, fetal malpresentation, and placental abnormalities. Cesarean Delivery, etc ETC The electron transport chain (ETC) sends electrons through a series of proteins, which generate an electrochemical proton gradient that produces energy in the form of adenosine triphosphate (ATP). Electron Transport Chain (ETC).)
• Abortion Abortion Expulsion of the product of fertilization before completing the term of gestation and without deliberate interference. Spontaneous Abortion: 
  • Number of lost pregnancies prior to the age of viability
  • Includes both spontaneous abortions (i.e., miscarriages) and induced terminations of pregnancy
• Last menstrual period (LMP): the 1st day of a woman’s LMP
• Gestational age: the age of pregnancy calculated from the LMP
• Embryonic age: the age of pregnancy calculated from the day of fertilization Fertilization To undergo fertilization, the sperm enters the uterus, travels towards the ampulla of the fallopian tube, and encounters the oocyte. The zona pellucida (the outer layer of the oocyte) deteriorates along with the zygote, which travels towards the uterus and eventually forms a blastocyst, allowing for implantation to occur. Fertilization and First Week (not used in obstetric clinical practice)
• Estimated date of delivery (EDD): also known as the estimated date of confinement

Sequence of events

• Fertilization Fertilization To undergo fertilization, the sperm enters the uterus, travels towards the ampulla of the fallopian tube, and encounters the oocyte. The zona pellucida (the outer layer of the oocyte) deteriorates along with the zygote, which travels towards the uterus and eventually forms a blastocyst, allowing for implantation to occur. Fertilization and First Week of the oocyte by a sperm → embryo Embryo The entity of a developing mammal, generally from the cleavage of a zygote to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the fetus. Fertilization and First Week
• Implantation Implantation Endometrial implantation of embryo, mammalian at the blastocyst stage. Fertilization and First Week of the early embryo Embryo The entity of a developing mammal, generally from the cleavage of a zygote to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the fetus. Fertilization and First Week into the uterine wall
• Fetal and placental differentiation, growth, and development
• Concurrent changes occur in the mother’s body to support the developing fetus and prepare for delivery.
• Labor Labor Labor is the normal physiologic process defined as uterine contractions resulting in dilatation and effacement of the cervix, which culminates in expulsion of the fetus and the products of conception. Normal and Abnormal Labor and delivery of the infant
• Puerperium: return of the mother’s body to the prepregnant state

Pregnancy duration

• Pregnancy is counted by completed weeks + completed days of the current week since the LMP:
  • Known as weeks gestational age (wga)
  • E.g., 35 + 4 wga would indicate that an infant is 35 weeks and 4 days gestational age
• Duration of normal pregnancy: 
  • Full-term pregnancy: 37–42 wga
  • Preterm pregnancy: < 37 wga
  • Post-term pregnancy: > 42 wga
  • Notes: Only about 5% of women deliver on their EDD.
• Classified into trimesters:
  • 1st trimester: 0–13 + 6 wga 
  • 2nd trimester: 14 + 0 to 27 + 6 wga
  • 3rd trimester: 28 + 0 wga through delivery

Clinical Presentation

Individuals trying to get pregnant will typically present with a positive home pregnancy test. Many others may not know they are pregnant and will present with symptoms of early pregnancy, which may include:

• Missed periods ( amenorrhea Amenorrhea Absence of menstruation. Congenital Malformations of the Female Reproductive System)
• Irregular bleeding (especially in cases of ectopic pregnancy Ectopic pregnancy Ectopic pregnancy refers to the implantation of a fertilized egg (embryo) outside the uterine cavity. The main cause is disruption of the normal anatomy of the fallopian tube. Ectopic Pregnancy and/or miscarriage Miscarriage Spontaneous abortion, also known as miscarriage, is the loss of a pregnancy before 20 weeks’ gestation. However, the layperson use of the term “abortion” is often intended to refer to induced termination of a pregnancy, whereas “miscarriage” is preferred for spontaneous loss. Spontaneous Abortion)
• Pelvic or abdominal pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways/discomfort
• Breast engorgement Engorgement Mastitis and tenderness
• Nausea Nausea An unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses. Antiemetics and vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia
• Fatigue Fatigue The state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli. Fibromyalgia
• Frequent urination (typically later in pregnancy)

Diagnosis of Pregnancy and Establishing the EDD

Pregnancy is confirmed based on lab tests and obstetric ultrasound imaging. 

Laboratory

The major analyte Analyte The molecule of interest (antigen) Immunoassays used to establish pregnancy is β-hCG. 

• β-hCG is a hormone produced early by the developing embryo Embryo The entity of a developing mammal, generally from the cleavage of a zygote to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the fetus. Fertilization and First Week.
• The presence of β-hCG indicates pregnancy.
• β-hCG tests may be:
  • Qualitative: to detect the presence or absence of β-hCG
    • Urine tests (available as over-the-counter kits) or a test at a medical lab
    • Reliable approximately 2 weeks after fertilization Fertilization To undergo fertilization, the sperm enters the uterus, travels towards the ampulla of the fallopian tube, and encounters the oocyte. The zona pellucida (the outer layer of the oocyte) deteriorates along with the zygote, which travels towards the uterus and eventually forms a blastocyst, allowing for implantation to occur. Fertilization and First Week
  • Quantitative: to determine serum β-hCG levels
    • Serum tests
    • More sensitive, reliable 6–10 days after fertilization Fertilization To undergo fertilization, the sperm enters the uterus, travels towards the ampulla of the fallopian tube, and encounters the oocyte. The zona pellucida (the outer layer of the oocyte) deteriorates along with the zygote, which travels towards the uterus and eventually forms a blastocyst, allowing for implantation to occur. Fertilization and First Week 
    • Can be used to track β-hCG levels when there is a concern for an abnormal pregnancy (e.g., ectopic pregnancy Ectopic pregnancy Ectopic pregnancy refers to the implantation of a fertilized egg (embryo) outside the uterine cavity. The main cause is disruption of the normal anatomy of the fallopian tube. Ectopic Pregnancy or miscarriage Miscarriage Spontaneous abortion, also known as miscarriage, is the loss of a pregnancy before 20 weeks’ gestation. However, the layperson use of the term “abortion” is often intended to refer to induced termination of a pregnancy, whereas “miscarriage” is preferred for spontaneous loss. Spontaneous Abortion)
    • Levels should roughly double every 24–48 hours during the 1st month.

Imaging

• Ultrasound is the obstetric imaging Obstetric imaging Obstetric imaging refers to imaging of the female reproductive tract and developing fetus during pregnancy. Ultrasonography is the 1st-line imaging modality during pregnancy as it does not emit radiation; thus, it is the safest option for the developing fetus. Obstetric Imaging modality of choice to diagnose and date a pregnancy.
• Purpose of early ultrasounds:
  • Viability: to establish if a viable pregnancy is present
  • To determine the number of fetuses
  • To establish the location of the pregnancy (e.g., rule out ectopic pregnancy Ectopic pregnancy Ectopic pregnancy refers to the implantation of a fertilized egg (embryo) outside the uterine cavity. The main cause is disruption of the normal anatomy of the fallopian tube. Ectopic Pregnancy)
  • Dating
• 1st-trimester findings: 
  • Presence of a gestational sac:
    • 1st visible finding of pregnancy is seen around 4.5–5 wga.
    • A hypoechoic Hypoechoic A structure that produces a low-amplitude echo (darker grays) Ultrasound (Sonography) circle within the uterine cavity, surrounded by hyperechoic Hyperechoic A structure that produces a high-amplitude echo (lighter grays and white) Ultrasound (Sonography) endometrium Endometrium The mucous membrane lining of the uterine cavity that is hormonally responsive during the menstrual cycle and pregnancy. The endometrium undergoes cyclic changes that characterize menstruation. After successful fertilization, it serves to sustain the developing embryo. Embryoblast and Trophoblast Development
    • Should be visible in the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy if quantitative serum β-hCG is > 2,000
  • Presence of a yolk sac Yolk Sac The first of four extra-embryonic membranes to form during embryogenesis. In reptiles and birds, it arises from endoderm and mesoderm to incorporate the egg yolk into the digestive tract for nourishing the embryo. In placental mammals, its nutritional function is vestigial; however, it is the source of intestinal mucosa; blood cells; and germ cells. It is sometimes called the vitelline sac, which should not be confused with the vitelline membrane of the egg. Embryoblast and Trophoblast Development: 
    • A thin hyperechoic Hyperechoic A structure that produces a high-amplitude echo (lighter grays and white) Ultrasound (Sonography) ring within the gestational sac
    • 1st seen approximately 5–6 wga and disappears around 10 wga
  • Presence of a fetal pole with a heartbeat: seen around 5.5–6 wga
• Dating a pregnancy using ultrasound:
  • 1st trimester: measuring the crown-rump length Crown-Rump Length Obstetric Imaging of the fetal pole 
  • 2nd and 3rd trimesters: calculated using a formula by considering measurements of biparietal diameter, abdominal circumference, and femur length

Establishing the EDD

Establishing the EDD is one of the most important factors to accomplish after diagnosing a pregnancy. Dating a pregnancy is usually done by calculating the EDD from the LMP and comparing that date with the EDD obtained from early ultrasound measurements.

• Calculating the EDD from the LMP:
  • The date that falls exactly 40 weeks after the LMP
  • Calculated by adding 280 days (or 9 months and 7 days) to the LMP
• Dating by ultrasound:
  • Measure the crown-rump length Crown-Rump Length Obstetric Imaging and look up the associated date in a table (most ultrasound machines will show this along with the measurement).
  • Ultrasound dating is most accurate in the 1st trimester before genetic variation and the effects of intrauterine environment begin to have greater effects on fetal growth.
• Establishing the final EDD:
  • Use the EDD obtained from the LMP if the EDD obtained from the crown-rump length Crown-Rump Length Obstetric Imaging measurement is within:
    • 5 days of the LMP-EDD for pregnancies < 9 wga
    • 7 days of the LMP-EDD for pregnancies 9–13 + 6 wga
    • Approximately 2 weeks in the 2nd trimester
    • Approximately 3 weeks in the 3rd trimester
  • Use the EDD obtained from ultrasound if the EDDs are further apart from each other than the dates listed above.
• Calculating the EDD from the LMP is the most accurate method to date a pregnancy if that EDD is consistent with the dates obtained from the ultrasound.
• If the LMP is unknown, a 1st-trimester ultrasound is the next most accurate way to date a pregnancy.

Physiological Changes During Pregnancy

To support fetal growth and development and prepare the mother’s body for eventual delivery, numerous anatomic and physiologic changes occur within a woman’s body during pregnancy.

Reproductive tract

Uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy:

• Increased uterine size:
  • Mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast ↑ from approximately 70 grams to 1100 grams
  • Volume capacity ↑ from approximately 10 mL to 5 L
  • Hypertrophy Hypertrophy General increase in bulk of a part or organ due to cell enlargement and accumulation of fluids and secretions, not due to tumor formation, nor to an increase in the number of cells (hyperplasia). Cellular Adaptation of the uterine wall with an accumulation of fibrous Fibrous Fibrocystic Change and elastic Elastic Connective Tissue: Histology tissue
  • Growth is initiated through ↑ estrogen Estrogen Compounds that interact with estrogen receptors in target tissues to bring about the effects similar to those of estradiol. Estrogens stimulate the female reproductive organs, and the development of secondary female sex characteristics. Estrogenic chemicals include natural, synthetic, steroidal, or non-steroidal compounds. Ovaries: Anatomy levels
  • By 28 wga, uterine growth slows and the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy continues to stretch and become thinner.
• Blood flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure: ↑ from 50 mL/min to 450–750 mL/min at term 
• Muscle contraction:
  • Uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy is maintained in a passive noncontractile state through ↑ levels of progesterone Progesterone The major progestational steroid that is secreted primarily by the corpus luteum and the placenta. Progesterone acts on the uterus, the mammary glands and the brain. It is required in embryo implantation; pregnancy maintenance, and the development of mammary tissue for milk production. Progesterone, converted from pregnenolone, also serves as an intermediate in the biosynthesis of gonadal steroid hormones and adrenal corticosteroids. Gonadal Hormones (a smooth muscle relaxant)
  • Braxton-Hicks contractions: 
    • Irregular contractions that do not cause cervical change
    • More noticeable as the pregnancy progresses 
• Uterine involution: return of the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy to its pre-pregnant state in the 1st several weeks postpartum

Cervix Cervix The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Externally, the cervix is lined by stratified squamous cells; however, the cervical canal is lined by columnar epithelium. Uterus, Cervix, and Fallopian Tubes: Anatomy:

• Cervix Cervix The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Externally, the cervix is lined by stratified squamous cells; however, the cervical canal is lined by columnar epithelium. Uterus, Cervix, and Fallopian Tubes: Anatomy softens and can become bluish due to:
  • Edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema
  • Increased vascularization
  • Hypertrophy Hypertrophy General increase in bulk of a part or organ due to cell enlargement and accumulation of fluids and secretions, not due to tumor formation, nor to an increase in the number of cells (hyperplasia). Cellular Adaptation and hyperplasia Hyperplasia An increase in the number of cells in a tissue or organ without tumor formation. It differs from hypertrophy, which is an increase in bulk without an increase in the number of cells. Cellular Adaptation of the cervical glands
• May undergo eversion Eversion Chronic Apophyseal Injury:
  • Glandular cells normally lining the cervical canal Cervical canal Uterus, Cervix, and Fallopian Tubes: Anatomy become visible on the surface of the cervix Cervix The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Externally, the cervix is lined by stratified squamous cells; however, the cervical canal is lined by columnar epithelium. Uterus, Cervix, and Fallopian Tubes: Anatomy.
  • Can cause benign Benign Fibroadenoma bleeding (all bleeding in pregnancy should be fully worked up)
• Endocervical mucosal cells produce a mucus plug, an immunological barrier for uterine contents.

Ovaries Ovaries Ovaries are the paired gonads of the female reproductive system that contain haploid gametes known as oocytes. The ovaries are located intraperitoneally in the pelvis, just posterior to the broad ligament, and are connected to the pelvic sidewall and to the uterus by ligaments. These organs function to secrete hormones (estrogen and progesterone) and to produce the female germ cells (oocytes). Ovaries: Anatomy:

• Ovulation Ovulation The discharge of an ovum from a rupturing follicle in the ovary. Menstrual Cycle and follicle development are suppressed by ↑ estrogen Estrogen Compounds that interact with estrogen receptors in target tissues to bring about the effects similar to those of estradiol. Estrogens stimulate the female reproductive organs, and the development of secondary female sex characteristics. Estrogenic chemicals include natural, synthetic, steroidal, or non-steroidal compounds. Ovaries: Anatomy levels
• The corpus luteum Corpus Luteum The yellow body derived from the ruptured ovarian follicle after ovulation. The process of corpus luteum formation, luteinization, is regulated by luteinizing hormone. Ovaries: Anatomy supplies progesterone Progesterone The major progestational steroid that is secreted primarily by the corpus luteum and the placenta. Progesterone acts on the uterus, the mammary glands and the brain. It is required in embryo implantation; pregnancy maintenance, and the development of mammary tissue for milk production. Progesterone, converted from pregnenolone, also serves as an intermediate in the biosynthesis of gonadal steroid hormones and adrenal corticosteroids. Gonadal Hormones during the 1st part of pregnancy until the placenta Placenta A highly vascularized mammalian fetal-maternal organ and major site of transport of oxygen, nutrients, and fetal waste products. It includes a fetal portion (chorionic villi) derived from trophoblasts and a maternal portion (decidua) derived from the uterine endometrium. The placenta produces an array of steroid, protein and peptide hormones (placental hormones). Placenta, Umbilical Cord, and Amniotic Cavity is developed enough to take over this function.

Anatomic and physiologic changes in pregnancy by system

Skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions changes

• Stretch marks
• Hyperpigmentation Hyperpigmentation Excessive pigmentation of the skin, usually as a result of increased epidermal or dermal melanin pigmentation, hypermelanosis. Hyperpigmentation can be localized or generalized. The condition may arise from exposure to light, chemicals or other substances, or from a primary metabolic imbalance. Malassezia Fungi of:
  • Face (known as melasma Melasma Melasma is a benign skin condition characterized by hyperpigmentation of sun-exposed regions due to excess melanin production and deposition. The condition mainly affects women during their reproductive years, particularly those with darker skin tones. Melasma, or the “mask of pregnancy”)
  • Nipples
  • Perineum Perineum The body region lying between the genital area and the anus on the surface of the trunk, and to the shallow compartment lying deep to this area that is inferior to the pelvic diaphragm. The surface area is between the vulva and the anus in the female, and between the scrotum and the anus in the male. Vagina, Vulva, and Pelvic Floor: Anatomy
  • Abdominal line (known as the linea nigra)
  • Umbilicus
• Spider angiomata Spider Angiomata Portal Hypertension
• Palmar erythema Erythema Redness of the skin produced by congestion of the capillaries. This condition may result from a variety of disease processes. Chalazion

Normal Prenatal Care

Appointment schedule

The typical schedule of prenatal visits for low-risk individuals:

• Every 4 weeks up through 28 wga
• Every 2 weeks from 28–36 wga
• Every week from 36 wga until delivery

Prenatal visits

Parameters to measure/monitor for healthy, uncomplicated individuals at routine prenatal visits:

• 1st visit:
  • Ultrasound to confirm the estimated date of confinement (either in-office or ordered)
  • Full physical exam, including a pelvic exam
  • Recommend supplements: 
    • Folic acid (best if started prior to pregnancy)
    • Multivitamins with iron Iron A metallic element with atomic symbol fe, atomic number 26, and atomic weight 55. 85. It is an essential constituent of hemoglobins; cytochromes; and iron-binding proteins. It plays a role in cellular redox reactions and in the transport of oxygen. Trace Elements
• All visits:
  • Weight
  • Blood pressure
  • Fetal HR (using doppler Doppler Ultrasonography applying the doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. Ultrasound (Sonography) auscultation)
  • Ask the mother about:
    • Abnormal bleeding
    • Contraction-like or cramping abdominal pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways
    • Abnormal loss of fluid
• Starting at 20 wga: fundal height measurements
• Starting at 28 wga, ask the mother about: 
  • Fetal movements:
    • Should experience 10 movements in a 2-hour period at least once daily
    • Individuals who report decreased fetal movement should be evaluated.
  • TDaP immunization (once)
  • Rh immunoglobulin to Rh-negative women
• Starting at 34–36 wga: Assess fetal presentation Fetal presentation Fetal presentation describes which part of the fetus will enter through the cervix first, while position is the orientation of the fetus compared to the maternal bony pelvis. Presentations include vertex (the fetal occiput will present through the cervix first), face, brow, shoulder, and breech. Fetal Malpresentation and Malposition (vertex or breech).

Routine pregnancy laboratory and imaging studies

All pregnant individuals should have certain labs done at different points during their pregnancy. These include:

• At their 1st obstetrics appointment:
  • CBC
  • Blood type and screen (may indicate future compatibility issues with fetal blood type)
  • Urinalysis Urinalysis Examination of urine by chemical, physical, or microscopic means. Routine urinalysis usually includes performing chemical screening tests, determining specific gravity, observing any unusual color or odor, screening for bacteriuria, and examining the sediment microscopically. Urinary Tract Infections (UTIs) in Children
  • Rubella Rubella An acute infectious disease caused by the rubella virus. The virus enters the respiratory tract via airborne droplet and spreads to the lymphatic system. Rubella Virus immunity status
  • HIV HIV Anti-HIV Drugs
  • Hepatitis B Hepatitis B Hepatitis B virus (HBV) is a partially double-stranded DNA virus, which belongs to the Orthohepadnavirus genus and the Hepadnaviridae family. Most individuals with acute HBV infection are asymptomatic or have mild, self-limiting symptoms. Chronic infection can be asymptomatic or create hepatic inflammation, leading to liver cirrhosis and hepatocellular carcinoma (HCC). Hepatitis B Virus surface antigen Antigen Substances that are recognized by the immune system and induce an immune reaction. Vaccination
  • Rapid plasma reagin test Rapid plasma reagin test Treponema for syphilis Syphilis Syphilis is a bacterial infection caused by the spirochete Treponema pallidum pallidum (T. p. pallidum), which is usually spread through sexual contact. Syphilis has 4 clinical stages: primary, secondary, latent, and tertiary. Syphilis
  • Gonorrhea Gonorrhea Gonorrhea is a sexually transmitted infection (STI) caused by the gram-negative bacteria Neisseria gonorrhoeae (N. gonorrhoeae). Gonorrhea may be asymptomatic but commonly manifests as cervicitis or urethritis with less common presentations such as proctitis, conjunctivitis, or pharyngitis. Gonorrhea and chlamydia Chlamydia Chlamydiae are obligate intracellular gram-negative bacteria. They lack a peptidoglycan layer and are best visualized using Giemsa stain. The family of Chlamydiaceae comprises 3 pathogens that can infect humans: Chlamydia trachomatis, Chlamydia psittaci, and Chlamydia pneumoniae. Chlamydia testing
  • Pap smear Pap smear Cytological preparation of cells collected from a mucosal surface and stained with Papanicolaou stain. Cervical Cancer Screening (only if due for routine Pap screening Screening Preoperative Care)
  • Screening Screening Preoperative Care for inherited diseases based on ethnicity (e.g., hemoglobinopathies Hemoglobinopathies A group of inherited disorders characterized by structural alterations within the hemoglobin molecule. Anemia: Overview and Types, cystic fibrosis Cystic fibrosis Cystic fibrosis is an autosomal recessive disorder caused by mutations in the gene CFTR. The mutations lead to dysfunction of chloride channels, which results in hyperviscous mucus and the accumulation of secretions. Common presentations include chronic respiratory infections, failure to thrive, and pancreatic insufficiency. Cystic Fibrosis)
• Screening Screening Preoperative Care for fetal aneuploidy (e.g., trisomy Trisomy The possession of a third chromosome of any one type in an otherwise diploid cell. Types of Mutations 21):
  • Multiple options available
  • Options include different combinations of multiple serum analytes and ultrasound.
  • A common option used is a test assessing the cell-free fetal DNA DNA A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine). DNA Types and Structure found in maternal serum (often referred to as noninvasive prenatal testing (NIPT)).
• Other tests:
  • Full anatomic assessment of the fetus, placenta Placenta A highly vascularized mammalian fetal-maternal organ and major site of transport of oxygen, nutrients, and fetal waste products. It includes a fetal portion (chorionic villi) derived from trophoblasts and a maternal portion (decidua) derived from the uterine endometrium. The placenta produces an array of steroid, protein and peptide hormones (placental hormones). Placenta, Umbilical Cord, and Amniotic Cavity, and uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy/ cervix Cervix The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Externally, the cervix is lined by stratified squamous cells; however, the cervical canal is lined by columnar epithelium. Uterus, Cervix, and Fallopian Tubes: Anatomy at 18–22 wga 
  • 1-hour glucose tolerance test Glucose Tolerance Test A test to determine the ability of an individual to maintain homeostasis of blood glucose. It includes measuring blood glucose levels in a fasting state, and at prescribed intervals before and after oral glucose intake (75 or 100 g) or intravenous infusion (0. 5 g/kg). Physical Examination of the Newborn (GTT) at 24–28 wga
  • CBC is often repeated with GTT.
  • Group B Streptococcus Streptococcus Streptococcus is one of the two medically important genera of gram-positive cocci, the other being Staphylococcus. Streptococci are identified as different species on blood agar on the basis of their hemolytic pattern and sensitivity to optochin and bacitracin. There are many pathogenic species of streptococci, including S. pyogenes, S. agalactiae, S. pneumoniae, and the viridans streptococci. Streptococcus culture at 35–37 wga
  • Bedside ultrasound to check fetal presentation Fetal presentation Fetal presentation describes which part of the fetus will enter through the cervix first, while position is the orientation of the fetus compared to the maternal bony pelvis. Presentations include vertex (the fetal occiput will present through the cervix first), face, brow, shoulder, and breech. Fetal Malpresentation and Malposition (vertex/head down, breech/buttocks down) around 35 wga

Diet, exercise, and weight gain

Weight gain:

The recommended weight gain during pregnancy is based on the individual’s prepregnancy BMI BMI An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity. Normal weight-gain recommendations:

• Underweight ( BMI BMI An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity < 18.5): 28–40 lbs
• Normal weight ( BMI BMI An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity 18.5–24.9): 25–35 lbs
• Overweight ( BMI BMI An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity 25–29.9): 15–25 lbs
• Obese ( BMI BMI An indicator of body density as determined by the relationship of body weight to body height. Bmi=weight (kg)/height squared (m2). Bmi correlates with body fat (adipose tissue). Their relationship varies with age and gender. For adults, bmi falls into these categories: below 18. 5 (underweight); 18. 5-24. 9 (normal); 25. 0-29. 9 (overweight); 30. 0 and above (obese). Obesity > 30): 11–20 lbs
• Note: Weight loss Weight loss Decrease in existing body weight. Bariatric Surgery is not recommended during pregnancy.

Exercise:

• Purpose: controls weight gain, improves delivery, improves weight loss Weight loss Decrease in existing body weight. Bariatric Surgery after pregnancy
• Recommendation: moderate exercise for 30 minutes on most days of the week
• In general, women can continue performing exercises they were doing prior to pregnancy at the same level of intensity (goal: maintain fitness level rather than increasing exercise intensity).
• Avoid contact sports and/or activities associated with the risk of falling or abdominal trauma (e.g., soccer, horseback riding, downhill skiing).
• Avoid exercising in hot weather.

Safety

• Air travel is safe for up to 36 weeks (after which, the risk of labor Labor Labor is the normal physiologic process defined as uterine contractions resulting in dilatation and effacement of the cervix, which culminates in expulsion of the fetus and the products of conception. Normal and Abnormal Labor or complications on board ↑).
• Precautions to prevent deep vein thrombosis Deep vein thrombosis Deep vein thrombosis (DVT) usually occurs in the deep veins of the lower extremities. The affected veins include the femoral, popliteal, iliofemoral, and pelvic veins. Proximal DVT is more likely to cause a pulmonary embolism (PE) and is generally considered more serious. Deep Vein Thrombosis during long trips (both flights and road trips):
  • Compression Compression Blunt Chest Trauma stockings
  • Frequent hydration
  • Frequent ambulation in the airplane or at rest stops (every 1–2 hours)
• Frequent handwashing
• Avoid kitty litter (to ↓ risk of toxoplasmosis Toxoplasmosis Toxoplasmosis is an infectious disease caused by Toxoplasma gondii, an obligate intracellular protozoan parasite. Felines are the definitive host, but transmission to humans can occur through contact with cat feces or the consumption of contaminated foods. The clinical presentation and complications depend on the host’s immune status. Toxoplasma/Toxoplasmosis).

Common Discomforts of Pregnancy

Pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways

• Pregnancy hormones Hormones Hormones are messenger molecules that are synthesized in one part of the body and move through the bloodstream to exert specific regulatory effects on another part of the body. Hormones play critical roles in coordinating cellular activities throughout the body in response to the constant changes in both the internal and external environments. Hormones: Overview and Types (e.g., progesterone Progesterone The major progestational steroid that is secreted primarily by the corpus luteum and the placenta. Progesterone acts on the uterus, the mammary glands and the brain. It is required in embryo implantation; pregnancy maintenance, and the development of mammary tissue for milk production. Progesterone, converted from pregnenolone, also serves as an intermediate in the biosynthesis of gonadal steroid hormones and adrenal corticosteroids. Gonadal Hormones, relaxin) cause ligaments to stretch more easily and ↑ water retention
• Common pains:
  • Pelvic pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways from stretching at the pubic symphysis Pubic Symphysis A slightly movable cartilaginous joint which occurs between the pubic bones. Vagina, Vulva, and Pelvic Floor: Anatomy and sacroiliac joints → maternity support belts can help
  • Round ligament Round ligament A fibromuscular band that attaches to the uterus and then passes along the broad ligament, out through the inguinal ring, and into the labium majus. Uterus, Cervix, and Fallopian Tubes: Anatomy pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways (described subsequently)
  • Foot Foot The foot is the terminal portion of the lower limb, whose primary function is to bear weight and facilitate locomotion. The foot comprises 26 bones, including the tarsal bones, metatarsal bones, and phalanges. The bones of the foot form longitudinal and transverse arches and are supported by various muscles, ligaments, and tendons. Foot: Anatomy pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways
  • Low back pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways (from shifting center of gravity)
  • Carpal tunnel Carpal Tunnel The carpal tunnel is formed by the transverse carpal ligament (flexor retinaculum) superiorly and the carpal bones inferiorly. Carpal Tunnel Syndrome syndrome
• Round ligament Round ligament A fibromuscular band that attaches to the uterus and then passes along the broad ligament, out through the inguinal ring, and into the labium majus. Uterus, Cervix, and Fallopian Tubes: Anatomy pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways: 
  • Round ligaments attach the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy to the pelvic sidewall.
  • As the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy grows, the round ligaments can stretch and cause pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways.
  • Differentiating round ligament Round ligament A fibromuscular band that attaches to the uterus and then passes along the broad ligament, out through the inguinal ring, and into the labium majus. Uterus, Cervix, and Fallopian Tubes: Anatomy pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways ( benign Benign Fibroadenoma) from more concerning pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways:
    • Round ligament Round ligament A fibromuscular band that attaches to the uterus and then passes along the broad ligament, out through the inguinal ring, and into the labium majus. Uterus, Cervix, and Fallopian Tubes: Anatomy pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways is often unilateral.
    • On exam, push the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy toward the painful side; if this maneuver relieves pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways, it is likely round ligament Round ligament A fibromuscular band that attaches to the uterus and then passes along the broad ligament, out through the inguinal ring, and into the labium majus. Uterus, Cervix, and Fallopian Tubes: Anatomy pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways.
• Analgesics:
  • Acetaminophen Acetaminophen Acetaminophen is an over-the-counter nonopioid analgesic and antipyretic medication and the most commonly used analgesic worldwide. Despite the widespread use of acetaminophen, its mechanism of action is not entirely understood. Acetaminophen is the safest analgesic.
  • Try to avoid NSAIDs NSAIDS Primary vs Secondary Headaches due to their effects on the fetal kidneys Kidneys The kidneys are a pair of bean-shaped organs located retroperitoneally against the posterior wall of the abdomen on either side of the spine. As part of the urinary tract, the kidneys are responsible for blood filtration and excretion of water-soluble waste in the urine. Kidneys: Anatomy.

Gastrointestinal symptoms

• Nausea Nausea An unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses. Antiemetics and vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia:
  • Common especially in early pregnancy (colloquially, “morning sickness”)
  • More common in the mornings but may occur throughout the day
  • Often improves in the early 2nd trimester
  • Management:
    • Vitamin B6 Vitamin B6 Vitamin B 6 refers to several picolines (especially pyridoxine; pyridoxal; & pyridoxamine) that are efficiently converted by the body to pyridoxal phosphate which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, and aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate. Although pyridoxine and vitamin B 6 are still frequently used as synonyms, especially by medical researchers, this practice is erroneous and sometimes misleading. Most of vitamin b6 is eventually degraded to pyridoxic acid and excreted in the urine. Water-soluble Vitamins and their Deficiencies supplementation
    • Dietary changes: eat 1st thing in the morning. Consume smaller meals more frequently.
• Acid reflux/ heartburn Heartburn Substernal pain or burning sensation, usually associated with regurgitation of gastric juice into the esophagus. Gastroesophageal Reflux Disease (GERD)
• Constipation Constipation Constipation is common and may be due to a variety of causes. Constipation is generally defined as bowel movement frequency < 3 times per week. Patients who are constipated often strain to pass hard stools. The condition is classified as primary (also known as idiopathic or functional constipation) or secondary, and as acute or chronic. Constipation

Differential Diagnosis

Oligomenorrhea Oligomenorrhea Polycystic Ovarian Syndrome/ amenorrhea Amenorrhea Absence of menstruation. Congenital Malformations of the Female Reproductive System

The primary symptom of pregnancy is a “missed” menstrual cycle Menstrual cycle The menstrual cycle is the cyclic pattern of hormonal and tissular activity that prepares a suitable uterine environment for the fertilization and implantation of an ovum. The menstrual cycle involves both an endometrial and ovarian cycle that are dependent on one another for proper functioning. There are 2 phases of the ovarian cycle and 3 phases of the endometrial cycle. Menstrual Cycle. Pregnancy must always be ruled out using a simple urine-pregnancy test in reproductive-aged women presenting with abnormal bleeding. Other common causes of abnormal uterine bleeding Abnormal Uterine Bleeding Abnormal uterine bleeding is the medical term for abnormalities in the frequency, volume, duration, and regularity of the menstrual cycle. Abnormal uterine bleeding is classified using the acronym PALM-COEIN, with PALM representing the structural causes and COEIN indicating the non-structural causes. Abnormal Uterine Bleeding include:

• Polycystic ovarian syndrome Polycystic ovarian syndrome Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder of reproductive-age women, affecting nearly 5%-10% of women in the age group. It is characterized by hyperandrogenism, chronic anovulation leading to oligomenorrhea (or amenorrhea), and metabolic dysfunction. Polycystic Ovarian Syndrome: a metabolic condition resulting in abnormally elevated androgen levels that can suppress menstruation Menstruation The periodic shedding of the endometrium and associated menstrual bleeding in the menstrual cycle of humans and primates. Menstruation is due to the decline in circulating progesterone, and occurs at the late luteal phase when luteolysis of the corpus luteum takes place. Menstrual Cycle. Polycystic ovarian syndrome Polycystic ovarian syndrome Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder of reproductive-age women, affecting nearly 5%-10% of women in the age group. It is characterized by hyperandrogenism, chronic anovulation leading to oligomenorrhea (or amenorrhea), and metabolic dysfunction. Polycystic Ovarian Syndrome is typically treated with oral contraceptive Oral contraceptive Compounds, usually hormonal, taken orally in order to block ovulation and prevent the occurrence of pregnancy. The hormones are generally estrogen or progesterone or both. Benign Liver Tumors pills and lifestyle modifications to promote weight loss Weight loss Decrease in existing body weight. Bariatric Surgery.
• Hypothalamic amenorrhea Amenorrhea Absence of menstruation. Congenital Malformations of the Female Reproductive System: a condition in which the hypothalamus Hypothalamus The hypothalamus is a collection of various nuclei within the diencephalon in the center of the brain. The hypothalamus plays a vital role in endocrine regulation as the primary regulator of the pituitary gland, and it is the major point of integration between the central nervous and endocrine systems. Hypothalamus decreases gonadotropin-releasing hormone Gonadotropin-releasing hormone A decapeptide that stimulates the synthesis and secretion of both pituitary gonadotropins, luteinizing hormone and follicle stimulating hormone. Gnrh is produced by neurons in the septum preoptic area of the hypothalamus and released into the pituitary portal blood, leading to stimulation of gonadotrophs in the anterior pituitary gland. Puberty (GnRH) secretion Secretion Coagulation Studies, which in turn decreases the release Release Release of a virus from the host cell following virus assembly and maturation. Egress can occur by host cell lysis, exocytosis, or budding through the plasma membrane. Virology of follicle-stimulating hormone ( FSH FSH A major gonadotropin secreted by the adenohypophysis. Follicle-stimulating hormone stimulates gametogenesis and the supporting cells such as the ovarian granulosa cells, the testicular sertoli cells, and leydig cells. Fsh consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity. Menstrual Cycle), resulting in the suppression Suppression Defense Mechanisms of ovulation Ovulation The discharge of an ovum from a rupturing follicle in the ovary. Menstrual Cycle and menstruation Menstruation The periodic shedding of the endometrium and associated menstrual bleeding in the menstrual cycle of humans and primates. Menstruation is due to the decline in circulating progesterone, and occurs at the late luteal phase when luteolysis of the corpus luteum takes place. Menstrual Cycle. Hypothalamic amenorrhea Amenorrhea Absence of menstruation. Congenital Malformations of the Female Reproductive System most commonly arises in the setting of eating disorders and/or women athletes. Management typically involves nutritional support and psychotherapy Psychotherapy Psychotherapy is interpersonal treatment based on the understanding of psychological principles and mechanisms of mental disease. The treatment approach is often individualized, depending on the psychiatric condition(s) or circumstance. Psychotherapy.
• Premature Premature Childbirth before 37 weeks of pregnancy (259 days from the first day of the mother’s last menstrual period, or 245 days after fertilization). Necrotizing Enterocolitis ovarian insufficiency: a condition of premature Premature Childbirth before 37 weeks of pregnancy (259 days from the first day of the mother’s last menstrual period, or 245 days after fertilization). Necrotizing Enterocolitis menopause Menopause Menopause is a physiologic process in women characterized by the permanent cessation of menstruation that occurs after the loss of ovarian activity. Menopause can only be diagnosed retrospectively, after 12 months without menstrual bleeding. Menopause in which the ovarian follicles fail to ovulate starting at an abnormally young age. Management involves hormone replacement therapy Hormone Replacement Therapy Hormone replacement therapy (HRT) is used to treat symptoms associated with female menopause and in combination to suppress ovulation. Risks and side effects include uterine bleeding, predisposition to cancer, breast tenderness, hyperpigmentation, migraine headaches, hypertension, bloating, and mood changes. Noncontraceptive Estrogen and Progestins and fertility treatments as desired.

Pelvic pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways

Some individuals may present with pelvic pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways and/or bleeding, which are symptoms that are more concerning for an abnormal pregnancy. Again, pregnancy should always be tested for in these individuals using a urine-pregnancy test. If the test is positive, the differential diagnosis includes:

• Ectopic pregnancy Ectopic pregnancy Ectopic pregnancy refers to the implantation of a fertilized egg (embryo) outside the uterine cavity. The main cause is disruption of the normal anatomy of the fallopian tube. Ectopic Pregnancy: implantation Implantation Endometrial implantation of embryo, mammalian at the blastocyst stage. Fertilization and First Week of an embryo Embryo The entity of a developing mammal, generally from the cleavage of a zygote to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the fetus. Fertilization and First Week outside of the uterine cavity, most commonly in the fallopian tube Fallopian Tube A pair of highly specialized canals extending from the uterus to its corresponding ovary. They provide the means for ovum transport from the ovaries and they are the site of the ovum’s final maturation and fertilization. The fallopian tube consists of an interstitium, an isthmus, an ampulla, an infundibulum, and fimbriae. Its wall consists of three layers: serous, muscular, and an internal mucosal layer lined with both ciliated and secretory cells. Uterus, Cervix, and Fallopian Tubes: Anatomy. The growing embryo Embryo The entity of a developing mammal, generally from the cleavage of a zygote to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the fetus. Fertilization and First Week can lead to tubal rupture and internal hemorrhage, which is associated with a high rate of maternal morbidity Morbidity The proportion of patients with a particular disease during a given year per given unit of population. Measures of Health Status and mortality Mortality All deaths reported in a given population. Measures of Health Status when not treated promptly. 
• Threatened, spontaneous, incomplete, or missed abortion Missed abortion The retention in the uterus of a dead fetus two months or more after its death. Spontaneous Abortion (i.e., miscarriage Miscarriage Spontaneous abortion, also known as miscarriage, is the loss of a pregnancy before 20 weeks’ gestation. However, the layperson use of the term “abortion” is often intended to refer to induced termination of a pregnancy, whereas “miscarriage” is preferred for spontaneous loss. Spontaneous Abortion): Spontaneous abortion Spontaneous abortion Spontaneous abortion, also known as miscarriage, is the loss of a pregnancy before 20 weeks’ gestation. However, the layperson use of the term “abortion” is often intended to refer to induced termination of a pregnancy, whereas “miscarriage” is preferred for spontaneous loss. Spontaneous Abortion (SAB) refers to the spontaneous loss of a pregnancy with complete expulsion of the fetal tissue. A threatened abortion Threatened abortion Uterine bleeding from a gestation of less than 20 weeks without any cervical dilatation. It is characterized by vaginal bleeding, lower back discomfort, or midline pelvic cramping and a risk factor for miscarriage. Spontaneous Abortion means that symptoms are present (pelvic pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways and bleeding), suggesting an SAB is possible. A missed abortion Missed abortion The retention in the uterus of a dead fetus two months or more after its death. Spontaneous Abortion refers to a fetus that has died in utero but has not yet been expelled. An incomplete abortion Incomplete abortion Premature loss of pregnancy in which not all the products of conception have been expelled. Spontaneous Abortion refers to a fetus that has died but only a part of the fetal tissue has been expelled. Individuals are diagnosed and followed up with serial ultrasounds and, sometimes, by monitoring β-hCG levels.