Table of Contents
Confirming and Dating Pregnancy and Establishing Gestational Age
After a successful conception, the fertilized ovum is implanted into the endometrium where the placenta forms. It is responsible for the production of the hormone beta-HCG (human chorionic gonadotropin) which is typical for pregnancies. The increased amount of this hormone is used for the detection of pregnancies. It is considered as a reliable proof of pregnancy. The most reliable proof, though, is a sonographic examination.
Less reliable signs of pregnancy are the first movements of the child, palpation of the uterus, and first subjective signs of pregnancy. Among these signs is the growth of the mammary glands with a feeling of tightness and morning sickness (emesis).
During the 1st examinations, the expected date of birth is supposed to be calculated. However, the results of the sonographic examination are not very helpful yet, because the amniotic sac is too small and the crown-rump length cannot be measured yet. Therefore, the 1st day of the last menstruation is used to calculate the date. The following formula is called Naegele’s rule.
This rule is used for a normal cycle length (28 days). If the menstrual cycle deviates, days should be subtracted or added (extension of Naegele’s rule).
Preventive examinations should take place every 4 weeks in the first 4 months. In the following 3 months every 3 weeks, in the next 2 months every 2 weeks and in the last month once per week.
During every examination, blood pressure is controlled to preclude hypertension. The weight, the urine, and the hemogram are examined regularly.
As around 5% of all pregnant women develop gestational diabetes for the first time, blood glucose is tested routinely.
Ultrasound examinations take place in the 10th, 20th, and 30th weeks of pregnancy. Several parameters are controlled. Control of vitality and detection of malformations, as well as malpresentation of the fetus, are essential. In advanced pregnancy, malpresentation of the fetus is particularly important. Moreover, the placenta and the quantity of amniotic fluid are evaluated.
The bimanual gynecological examination is also important for prenatal care. It is carried out until the 16th week of pregnancy. After this, the so-called Leopold’s maneuvers are used. These serve to determine the fundal height, the position, the size of the child, and the quantity of amniotic fluid.
The first maneuver is used to determine the position of the child. Both hands of the examiner are placed close to the fundus. The fundal height can be estimated with this as well. Navel, xiphoid, and costal arches are used for orientation.
The second maneuver is carried out by placing the hands on both sides of the uterus. While doing this, the examiner can estimate the position of the back.
While carrying out the third maneuver, the right hand is placed at the pelvis. The thumb and fingers are used to identify the child’s head and other body parts. Through slightly sudden movements (ballottement) the flexibility of the head can be tested. If there is no flexibility, the child’s head already entered the pelvis.
The fourth maneuver is important to determine the relationship between the pelvis and the preceding part. The examiner faces the woman’s feet. Both hands are placed on the ulnar side in direction to the pubic bone.
To evaluate the cervix, vaginal examinations are carried out during the preventive appointments. During these appointments, it is important to estimate the width of the uterine orifice, the length of the cervix, the level, and the consistency of the cervix.
Control of fetal vitality is also an important part of the examination. This is assessed using ultrasound at the beginning of the pregnancy. The first heartbeat can be identified in the 5th week of pregnancy. The movements of the child are also signs of vitality. Typically, these can be determined by CTG (= cardiotocography).
First Trimester Bleeding
Bleedings during pregnancy can have different reasons. They are categorized according to the stages.
In the first half of the pregnancy, the reasons for bleeding can be abortion, nidation bleedings, trophoblastic tumors, ectopic pregnancy or cervical carcinoma.
If bleedings occur in the second half of the pregnancy, a placenta previa, a premature placenta abruption, a uterine rupture, a placental edge bleeding or a bloody show during feared delivery should be differentially diagnosed.
During birth, bleedings can occur as well. The reasons for this can be the uterine rupture, the bloody show, the premature placenta abruption or the insertio velamentosa. The insertio velamentosa is characterized by strong bleeding after the rupturing of the membranes and is a life-threatening danger to the child.
In the case of emergency, shock prevention, which would include a volume substitution, would be carried out. In a clinic, a surgical stopping of the bleeding would be attempted. If none of the measures are successful, a hysterectomy would be considered.
Fetal Alcohol Syndrome (FAS)
Etiology and epidemiology of the FAS
In all stages of pregnancy, alcohol is harmful to the embryo and the fetus. With a prevalence of 1:300, the FAS occurs more often than innate malformations such as Down’s syndrome.
However, the effects of alcohol, which affect the most sensitive human organ, are more frequent than FAS. The effects are characterized by, inter alia, brain achievement weakness, behavioral changes, and behavioral problems.
Alcohol and its metabolites harm the body’s cells, especially tissues with a high regenerative capacity. The substance can be compared to a mitotic toxin. Consequently, the growth of the child is restricted and results in hypoplasia or hypotrophy.
An important aspect of the cumulative occurrence of alcohol abuse is social class. Studies proved that socially disadvantaged women give birth to children with growth restriction more frequently. In middle-class women, this phenomenon occurred only rarely.
Affected children are usually smaller and have low body weight. In this context, the reduced weight can be traced back to muscle hypertrophy.
Typical characteristics are craniofacial changes of the children. In various tissues the hypertrophy expresses itself in a particularly strong way: frequently, the lower jaw is shifted back (maxillary hypertrophy), the lips are narrow and drawn-in. Rarely, the mouth is large and broad. The philtrum is narrow and frequently grouped due to the maxillary hypertrophy. Usually, the nasal bridge is missing, which gives the impression of a ‘snub nose’. Very often, the palpebral fissure at the eyes is narrowed and horizontally shortened.
The FAS is characterized by growth disorders, organic damages of the cerebrum and the cerebellum as well as minor and major abnormalities. These disorders occur in particular after heavy abuse of alcohol by the pregnant woman.
Embryopathies caused by infections
The infections that are most feared are members of the TORCHES complex which pose a risk to the mother and an additional risk of inducing embryologic abnormalities in the fetus. The effects of these infections range from abortion through embryopathy and fetopathy to long-term damage to the child.
Amniotic infection syndrome
During amniotic infection syndrome, bacterial colonization of the fetal membranes occurs. Usually, this happens due to the ascension of bacteria through the vagina. Moreover, a hematogenic spread of bacteria from another source of infection is possible. For example, a spread from the urogenital tract.
Infections signs such as fever, a painful uterus, and bad-smelling fluorine can be determined. The rupture of the membrane is also possible.
Premature rupture is excluded diagnostically and a bacteriological smear is taken from the pregnant woman. In certain periods, infectious disease markers such as C-reactive protein (CRP), leukocytes, and the blood sedimentation speed should be controlled. The fetus should be monitored by cardiotocography. During this procedure, it is very important to monitor a loss of oscillation or a rise in the baseline.
After birth, all findings should be given to the pediatrician to assure the intensive care of the newborn child.
Typical causes of the amniotic infection syndrome are, inter alia, Gardnerella vaginalis, Enterobacteriaceae, and Streptococci.
In a case of suspected streptococcus infection (type B) of the mother sub, part ampicillin should be given. After birth, the newborn child should be monitored for infection signs.