Prenatal care

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1. Factors of care during pregnancy,
screenings
Attila Molvarec, MD, PhD
1st Department of Obstetrics and Gynecology
Semmelweis University, Budapest, Hungary

2. Prenatal care
•A comprehensive antepartum care program that involves a
coordinated approach to medical care and psychosocial
support
•Optimally begins before conception and extends
throughout the antepartum period
•One of the most frequently used health services in
developed countries
•The average number of prenatal care visits is 12 per
pregnancy
•More than 80 percent of women initiate prenatal care in
the first trimester

3. Prenatal care
Contents:
•Preconceptional care
•Prompt diagnosis of pregnancy
•Initial presentation for pregnancy care
•Follow-up prenatal visits

4. Diagnosis of pregnancy
•Cessation of menses
•Positive home urine pregnancy test
•Detection of hCG in maternal blood or urine: 8-9
days after ovulation
•Ultrasonic recognition of pregnancy –0. (zero)
screening (transvaginal): gestational sac, yolk sac,
embryo with heartbeat

5. Diagnosis of pregnancy: ultrasonography

6. Initial prenatal care visit
Prenatal care should be initiated as soon as there is a
reasonable likelihood of pregnancy
The major goals:
•To define the health status of the mother and fetus
•To determine the gestational age of the fetus
•To initiate a plan for continuing obstetrical care

7. Recommended components of the initial
prenatal care visit (ACOG)
•Risk assessmentto include genetic, medical, obstetrical
and psychosocial factors
•Estimated due date
•General physical examination
•Laboratory tests:hematocrit (hemoglobin), urinanalysis,
urine culture, blood grouping, Rh, antibody screen, rubella
status, syphilis screen, Pap smear, HBsAg testing; offer
HIV testing
•Patient education, e.g. use of seatbelts, avoidance of
alcohol and tobacco

8. Assessment of gestational age
•The duration of pregnancy from the first day of the last
normal menstrual period (LMP) is 280 days or 40 weeks
(266 days (38 weeks) from conception)
•Naegele ruleto estimate the expected date of delivery
(EDD): add 7 days to the date of the first day of the LMP
and count back 3 months (menstrual history!)
•LMP: 20 September → EDD: 27 June
•We divide pregnancy into 3 trimesters of appx. 3 calendar
months (1-12, 13-24, 25-40)
•Clinicians designate gestational age using completed
weeks and days: 33+3 means 33 completed weeks and 3
days

9. Determination of fetal age: ultrasonography in the
first trimester –crown-rump length (CRL)

10. Taking a maternal history
•Almost a fourth of pregnant women have significant,
identifiable, treatable complications
•Major categories for increased risk:
(1) Preexisting medical illness
(2) Previous poor pregnancy outcome (perinatal mortality,
preterm delivery, IUGR, malformations, placental
accidents, maternal hemorrhage)
(3) Evidence of maternal undernutrition
•Detailed information concerning past obstetrical history is
crucial because most prior pregnancy complications tend
to recur in subsequent pregnancies

11. Psychosocial issues
•Cigarette smoking:spontaneous abortion, low birthweight
due to either preterm delivery or IUGR, infant and fetal
deaths, placental abruption, attention-deficit/hyperactivity
•Alcohol use:ethanol is a potent teratogen and causes the
fetal alcohol syndrome (IUGR, facial abnormalities, CNS
dysfunction-mental retardation)
•Illicit drugs(opium derivatives, barbiturates,
amphetamines): fetal distress, low birthweight, drug
withdrawal soon after birth
•Domestic violence:violence against adolescent and adult
females within the context of family or intimate
relationships
Increased risk of antepartum hemorrhage, IUGR, perinatal
death

12. Physical examination
Obstetrical examination
•The cervix is visualized using a speculum (bluish-red hyperemia is
characteristic of pregnancy), colposcopy
Chadwick sign: the vaginal mucosa appears dark bluish or purplish-
red and congested
•Pap smear, vaginal smear, specimens for identification of Neisseria
gonorrhoeae and Chlamydia trachomatis if screening is indicated
•Bimanual pelvic examination: cervix, corpus, bony architecture of
the pelvis
Hegar sign: softening at the isthmus; Piskacek sign: soft prominence
over the site of implantation
•Examination of the breasts
A thorough general physical examination with BMI, blood pressure,
pulse rate, ECG (family physician), dental examination

13. Hegar and Piskacek sign

14. Laboratory tests at the initial visit
•Complete blood count (WBC, Hb, Htc, Plt)
•Fasting glucose
•Liver and renal function parameters, coagulogram (if
indicated)
•Blood group, Rh, irregular antibody screening
•Lues serology
•HBsAg
•Urinanalysis: gravity, protein, glucose, pus, ubg, ketones

15. Subsequent prenatal visits
•At intervals of 4 weeks until 28 weeks
•Then every 2 weeks until 36 weeks
•Weekly thereafter
•In high-risk pregnancies: return visits at 1 to 2 week
intervals
•At each return visit,steps are taken to determine the well-
being of both the mother and her fetus (prenatal
surveillance)

16. Prenatal surveillance –fetal
•Heart rate(s): fetal stethoscope from 16-19 weeks, Doppler
equipment from 10 weeks, transvaginal US from 5-6
weeks
•Size –current and rate of change
•Amount of amnionic fluid
•Presenting part and station (late in pregnancy)
•Activity (fetal movements from 18-20 weeks)
•Non-stress test: from 35 weeks weekly, from 38 weeks
twice in a week, from 40 weeks daily
•Amnioscopy: from 40 weeks every second day

17. Leopold maneuvers –abdominal palpation
•First maneuver:height of the fundus, which fetal pole
(breech or head) occupies the uterine fundus
•Second maneuver:fetal lie and position
•Third maneuver:fetal presenting part (head, breech) and
its relationship to the pelvic inlet (engagement)
•Fourth maneuver:presenting part, engagement, descensus
of the head into the pelvis
•Fifth (Zangemeister) maneuver:cephalopelvic
disproportion (the head lies at the same level as or even
projects above the symphysis)

18. Leopold maneuvers

19. Zangemeistermaneuver

20. Non-stress test
A: Fetal heartbeat; B: Indicator showing movements felt by mother
(caused by pressing a button); C: Fetal movement; D: Uterine
contractions
Reactive NST:two or more accelerations of 15 beats/min or more,
each lasting at least 15 seconds within 20 minutes

21. Prenatal surveillance –maternal
•Blood pressure, pulse rate
•Weight: current and amount of change
•Complaints: headache, altered vision, abdominal pain, nausea and
vomiting, bleeding, vaginal fluid leakage, dysuria
•Height in centimeters of uterine fundus from symphysis (between 18
and 30 weeks in agreement with gestational age in weeks)
•Vaginal examination late in pregnancy:
Confirmation of the presenting part
Station of the presenting part
Clinical estimation of pelvic capacity and its general configuration
Consistency, effacement and dilatation of the cervix (CI)

22. Uterine fundal height
•20 weeks: 2 finger widths below
umbilicus
•24 weeks: at umbilicus
•28 weeks: 2 finger widths above
umbilicus
•32 weeks: 4 finger widths above
umbilicus
•35 weeks: between umbilicus and
xyphoid process
•36 weeks: 4 finger widths below
xyphoid process (xy/4)
•37 weeks: xy/3
•38 weeks: xy/2
•39 weeks: xy/3
•40 weeks: xy/4

23. Subsequent laboratory tests
•Complete blood count:each trimester
•Irregular antibodyscreening: Rh-negative women –each trimester
(Anti-D at 28 weeks), Rh-positive women –first and third trimester
•Serum alpha-fetoprotein (AFP)for open neural tube defects: at 16
weeks (15-20 weeks)-discontinued
•Gestational diabetesscreening (WHO): 75 g oral glucose tolerance
test (OGTT) at 24-28 weeks
•Urine sediment or culturefor bacteriuria: each trimester
•Vaginal smear(for bacterial vaginosis): each trimester
•Group B Streptococcus(GBS): vaginal and rectal cultures between
35 and 37 weeks (culture-based approach, ACOG recommendation)
•Screening for chlamydial and gonococcal infection(ACOG):
cervical culture in the first and third trimester in high-risk women
(unmarried, recent partner change, multiple partners, <25 years,
other STD)

24. Special screening for genetic diseases
Screening methods for aneuploidies (optional):
•Combined test:pregnancy-associated plasma protein-A
(PAPP-A), free ß-human chorionic gonadotropin (free ß-
hCG) and nuchal translucency (NT) at 11 (10-13)weeks
•Quadruple test:alpha-fetoprotein (AFP), total hCG,
unconjugated oestriol (uE3) and inhibin-A at 15-16 (14-
22)weeks
•Integrated test:NT and PAPP-A at 11 (10-13)weeks +
AFP, total hCG, uE3 and inhibin-A at 15-16 (14-22)
weeks
Cystic fibrosis, Tay-Sachs disease, β-and α-thalassemia,
sickle-cell anemia:screening can be offered based on
family history, or the ethnic or racial background of the
couple, ideally in the preconceptional period (ACOG)

25. Ultrasound screening (Hungarian protocol)
•0. screening: transvaginal diagnostic US in early
pregnancy
•1. screening (12-13 weeks):CRL (gestational age), nuchal
translucency, nasal bone
•2. screening (18-19 weeks):survey of fetal anatomy
(„genetic US”)
•3. screening (30-31 weeks):fetal size (IUGR)
•4. screening (36-37 weeks):information for delivery (fetal
lie, presentation, fetal size, location and maturity of
placenta, amnionic fluid volume)

26. Nutrition during pregnancy
•Maternal weight gain during pregnancy influences birthweight of the
infant
•Underweight women deliver smaller infants, whereas the opposite is
true for overweight women
•Excessive weight gain: hypertensive disorders, fetal macrosomia
•Limited weight gain: preterm birth, IUGR
•During the severe European winter of 1944-1945 in the Netherlands
occupied by the German military („Hunger Winter”), starvation was
associated with a decrease in median birthweight about 250 g, a
decline in the frequency of „toxemia”, but the perinatal mortality
rate was unchanged

27. Recommended total weight gain for singleton
pregnancies based on pre-pregnancy BMI
•Low(BMI<19.8): 12.5-18 kilograms
•Normal(19.8-26): 11.5-16 kg
•High(>26-29): 7-11.5 kg
•Obese(>29): <7 kg
•For women with twins: 16-20 kg
•The rate of weight gain should be about 0.7 pound (320
grams)/week from 8 to 20 weeks, while after 20 weeks
about 1 pound (450 grams)/week

28. Recommended dietary allowances
•Pregnancy requires an additional 80.000 kcal, which are
accumulated primarily in the last 20 weeks
•To meet this demand, a caloric increase of 100-300 kcal/dayis
recommended during pregnancy
•There are extra protein demands for growth and repair of the fetus,
placenta, uterus, breasts and increased maternal blood volume
•During the second half of pregnancy, about 1000 g of proteinare
deposited , amounting to 5-6 g/day
•Most protein should be supplied from animal sources, such as meat,
milk, eggs, cheese, poultry and fish, because they furnish amino
acids in optimal combinations
•Milk and dairy products are ideal sources of nutrients, especially
protein and calcium for pregnant or lactating women

29. Prenatal mineral supplementation
•With the exception of iron, practically all diets that supply
sufficient calories for appropriate weight gain will contain
enough minerals to prevent deficiency if iodized food is
used
•The iron requirements of normal pregnancy total appx.
1000 mg(300 mg transferred to the fetus and placenta,
200 mg lost through excretion, 500 mgfor
erythropoiesis), of which nearly all is used after
midpregnancy
•At least 30mg of ferrous iron supplementshould be given
daily from the second trimester, which amount is
contained in most prenatal vitamins

30. Prenatal vitamin supplementation
•The increased requirements for vitamins usually are
supplied by any general diet that provides adequate
calories and protein, except for folic acid
•Daily intake of 400 µg of folic acid throughout the
periconceptional period to prevent neural tube defects (4
mg/day for a woman with prior NTD)
•Routine multivitamin supplementation is not
recommended unless the maternal diet is questionable
(multiple gestation, substance abuse, complete
vegetarians, epileptics)

31. Pragmatic nutritional surveillance
•In general, advise the pregnant woman to eat what she wants in
amounts she desires and salted to taste
•Make sure that there is ample food to eat, especially in the case of
the socio-economically deprived woman
•Monitor weight gain, with a goal of about 11.5-16 kg in women
with a normal BMI
•Periodically explore food intake by dietary recall to discover the
occasional nutritionally absurd diet
•Give tablets of simple iron salts that provide at least 30 mg of
elemental iron daily. Give 400 µg daily of folate supplementation
before and in the early weeks of pregnancy
•Recheck the hematocrit (hemoglobin) at 28-32 weeks to detect any
significant decrease

32. Recommended daily dietary allowances

33. Preconceptional counseling
•Preventive medicine for obstetrics
•Factors that could potentially affect perinatal outcome are
identified, and the woman is advised of her risks
•Whenever possible, a strategy is provided to reduce or
eliminate the pathological influences revealed by her
family, medical or obstetrical history, or by specific
testing
•Has a measurable positive impact on pregnancy outcome
•By the time most women realize they are pregnant (1-2
weeks after the first missed period),the fetal spinal cord
has already formed and the heart is beating

34. Preconceptional counseling visit
•Medical history:maternal and fetal risks, pre-pregnancy
evaluation, change of medication (diabetes, hypertension,
epilepsy, heart disease, collagen vascular disorders, etc.)
•Genetic diseases:neural tube defects, phenylketonuria,
Tay-Sachs disease, thalassemias
•Reproductive history:infertility, need for assisted
reproductive technologies; outcomes of each prior
pregnancy: miscarriage, ectopic pregnancy, recurrent
pregnancy loss, preterm delivery; complications:
preeclampsia, gestational diabetes, placental abruption,
previous cesarean delivery (indication); reproductive
history of first-degree relatives (familial translocation)

35. Social history
Maternal age
•Teenagers are more likely to be anemic and are at increased risk for
IUGR, preterm labour, and consequent higher infant mortality;
STDs are more common during pregnancy; greater caloric
requirements (+400 kcal/day for normal and underweight
teenagers)
•Women over 35 are at increased risk for obstetrical complications,
perinatal morbidity and mortality if they have a chronic illness or
are in poor physical condition. For the normal weight, physically fit
woman without medical problems, the risks are not appreciably
increased. Fetal aneuploidy and dizygotic twinning increase with
maternal age, ART
Smoking, alcohol, recreational drugs
Domestic abuse:inquire about risk factors (partners abuse alcohol
or drugs, unemployed, have a poor education or low income,
history of arrest), offer intervention

36. Diet
•Many vegetarian diets are protein deficient, but can be corrected by
increasing egg and cheese consumption
•Obesity: maternal complications (hypertension, preeclampsia,
gestational diabetes, labor abnormalities, postterm pregnancy,
cesarean delivery, operative complications), adverse fetal outcomes
(spina bifida, ventral wall defects, late fetal death, preterm delivery)
•Anorexia, bulimia: nutritional deficiencies, electrolyte disturbances,
cardiac arrhythmias, gastrointestinal pathology, less weight gain,
smaller infants
Exercise:can continue (avoid supine position, augment heat
dissipation), but orthopedic injury (balance problems, joint
relaxation)
Environmental exposures:infectious organisms (CMV, RSV:
neonatal nurses; parvovirus, rubella: day-care workers), chemicals
(heavy metals, organic solvents: industrial workers; pesticides:
women living in rural areas; mercury: large fishes)

37. Family history
•The health and reproductive status of each „blood
relative” should be reviewed for medical illnesses, mental
retardation, birth defects, genetic disease, infertility and
pregnancy loss
•Certain racial or ethnic backgrounds may indicate
increased risk for specific recessive disorders
Immunizations
•Toxoids, killed bacteria and viruses have not been
associated with adverse fetal outcomes
•Live virus vaccines are not recommended during
pregnancy and ideally should be given at least 1 month
before attempts to conceive

38. Preconceptional screening tests, examinations
•Complete blood count (exclude inherited anemias)
•Rubella, varicella, hepatitis B immune status: vaccination
preconceptionally
•Carrier testing for genetic diseases based on family
history, racial or ethnic backgrounds, partners of carriers
(Tay-Sachs disease, cystic fibrosis, thalassemias, sickle-
cell anemia)
•Specific tests for chronic medical diseases: chronic renal
disease (serum creatinine can predict pregnancy
outcome), cyanotic heart disease (hemoglobin, arterial
oxygen saturation predict fetal outcome), insulin-
dependent diabetes (hemoglobin A
1C to compute risks for
major congenital anomalies)
•General physical, gynecological, dental examination