00:01
So now let's discussed routine
screening in pregnancy.
00:04
So here's a case.
00:06
A 23 year old G1 P0 intrauterine
pregnancy at 8 weeks and 5 days
presents for her
initial prenatal visit.
00:15
Which of the following test
would you not order as part
of her routine pintail
prenatal labs?
A. Complete blood count.
00:23
B. Maternal serum
alpha-fetoprotein.
00:26
C. Blood type and Rh factor.
00:29
or D. Human immunodeficient Virus (HIV) status.
00:32
Let's go throughout the lecture to find that answer.
00:36
So initial prenatal visit routine screening
this is actually discussed in
another lecture slide.
00:42
But we'll go through
this briefly.
00:44
First, blood type and Rh factor.
00:46
We do want to know a patient's
blood type and if they are
Rh negative or Rh positive.
00:52
Why is that?
Well if the patient is Rh
negative and the baby,
remember whose blood type
we don't know is Rh positive.
00:58
Mom can make antibodies against
positive blood types
and during her next pregnancy
if that baby is positive,
those antibodies will go
and attack that pregnancy.
01:08
So we want to know that we can
do preventive things during
the pregnancy, so that those
antigens and antibodies
don't cross.
01:15
So complete blood count.
01:18
We want to establish a normal
hemoglobin hematocrit
for the beginning of pregnancy.
01:22
Because we do know that
physiologically,
pregnant women do experience
anemias.
01:27
So we want to know
where they are starting.
01:29
So during our initial prenatal
visit routine screening,
there are some infections
that we need to screen for.
01:35
Let's talk about these
in a little detail.
01:38
First is rubella.
01:39
Now most women are rubella
immune because they did receive
vaccinations as children.
01:44
However, sometimes even with
the vaccines,
we do not build up the immunity
to rubella.
01:49
And to contract rubella during
pregnancy can means some
adverse outcomes for the fetus.
01:53
So it is recommended we screened
to determine if the patient is
rubella immune or non-immune
in the 1st trimester.
02:00
Unfortunately, if they are
non-immune, we're still not able
to give the vaccine
until after the delivery.
02:06
For HIV, the CDC says
that 50,000 people will be infected
by HIV every year.
02:13
So it is recommended that all
pregnant women get screened
as part of their initial prenatal visit.
02:18
If they are on a risk an area
that's high risk for HIV
or if they participate in
behaviors that will increase
their risk of contracting HIV,
it is recommended that
they also get screened in
the 3rd third trimester,
because of the affects it can
have on the fetus.
02:31
Moving on from there is
recommended that all women get
screened for syphilis
through the RPR or VDRL
in the 1st trimester.
02:41
If they are in a high risk area
for contracting syphilis,
it's recommended they get
screened in the 2nd and 3rd
trimester as well.
02:49
And for hepatitis B.
02:50
Because of the risk of
transmission to the fetus,
it's recommended that pregnant
women get screened for
hepatitis B at their initial prenatal visit.
02:58
And for hepatitis.
02:59
Because of the risk of transmission
to the fetus, ACOG
recommends that pregnant women
not only get screened for hepatitis B,
but also for hepatitis C
at their initial prenatal visit.
03:11
Now also as part of the initial
prenatal visit screening,
if the patient has not has
a pap smear in the last 3 years
and they are 21 years old,
it is recommended
they get pap smear for their
baseline labs.
03:25
As well as cultures for
gonorrhea and chlamydia.
03:28
Women should also be screened
for hemoglobinopathies
and genetic diseases.
03:34
In particular African American
women, they should be screened
for sickle-cell trait.
03:39
For Ashkenazi Jews,
they should be screened
for canavan's disease.
03:43
For Caucasian women they should
be screened for cystic fibrosis.
03:50
So back to our question A 23
year old G1 P0 intrauterine
pregnancy at 8 weeks 5 days
presents for her initial
prenatal visit.
03:59
Which of the following labs
would you not order as par
of her routine initial
prenatal labs?
A. Complete blood cell count
or CBC.
04:09
B. Maternal serum
alpha-fetoprotein.
04:11
C. Blood type and Rh factor.
04:14
or D. Human immunodeficient
Virus (HIV) status.
04:17
The answer is B.
04:19
Maternal serum
alpha-fetoprotein.
04:21
This is not part of the routine
screening lab.
04:26
Now, let's move on for
screening for Down syndrome.
04:29
We're going to discuss this in
great detail in another lecture.
04:33
But it's important to know that
while women of advance maternal
age are at increased risk for
having an infant with
Down's syndrome, all women
should be offered screening
in the 1st trimester.
04:45
So there are other routine
screening test that are done
through pregnancy.
04:48
One is the anatomy ultrasound.
04:50
This is done between 18
weeks and 22 weeks gestation.
04:53
And at this anatomy ultrasound,
we look at all structures of
the fetus to make sure they are
within normal limit.
04:59
We look at the brain.
05:00
We look at the heart,
the intestines.
05:03
Again, looking to see if there
is any structural abnormalities.
05:07
Screening for gestational
diabetes.
05:09
Now we have a look whole lecture
that's devoted
to gestational diabetes.
05:13
But into keep with our theme
and discuss about
how we screen for it,
this is done between 24
and 28 of weeks of pregnancy.
05:20
In the states, we do the 50 gram
glucola test.
05:23
And if a patient has a random
glucose level of 140 milligrams
per decaliter, they are
considered to have a positive
screen for gestational diabetes.
05:31
Though I should mention one caveat
based on current
guidelines, individual testing centers
are given the freedom to set their own
individual positive threshold,
which is usually between 130 and 140.
05:43
And this is really based on their patient
population and the prevalence of the disease.
05:48
So any value over 140 is considered
a positive screen, and certain patients
may also get a positive screen with values
slightly lower.
05:58
And then you need the
confirmation test which is
a 3 hour test.
06:01
In this test, they come
and get fasting blood sugar.
06:05
Drinking 100 gram glucola test
and they have blood sugar
at 1 hour, 2 hours and 3 hours.
06:12
If they have two values out of
those four lab values
that are abnormal, they have
gestational diabetes.
06:18
Now for women that are Rh
negative, again we discuss
the ill affects that can happen
in a pregnancy when a patient is
Rh negative.
06:29
And some of the preventive
measures that we do.
06:31
We give Rhogam at 28 weeks to
again help bind those antigens.
06:36
Since antibodies don't form
against an Rh positive fetus
in the next pregnancy.
06:41
So this is not a screening test,
but this is something that's
also recommended
for pregnant women.
06:47
That's the pertussis vaccination.
06:49
Because there's been a
resurgence of whopping cough,
the CDC recommends all women get
that vaccinated for pertussis
in the 3rd trimester.
06:57
And they're able to pass some
of that immunity on to the baby.
07:00
Now lastly,
we screen for group B beta streptococcus
for GB s at 36 to 38 weeks.
07:07
Historically, we have screen for GBS
between the gestational ages of 35 to 37 weeks.
07:14
However, ACOG and CDC have recommended
that we now screen later in pregnancy
beginning at 36 weeks
because we are allowing our mothers
to continue their pregnancy until 41 weeks.
07:28
For a mom that has a delivery at 41 weeks.
07:31
If she is screened at 35 weeks,
that culture is no longer valid.
07:37
So for this reason, ACOG
and the CDC have recommended
that we delay screening until 36 weeks.
07:43
Now GBS is a bacteria that's
part of the normal
vaginal flora.
07:47
However, if it's not treated
during delivery time,
specially a vaginal delivery,
then the [?] can contract this disease
and it can lead to
meningitis or pneumonia.
07:57
So it's very important to know
if a patient is positive for GBS
so that they can receive
the appropriate treatment.