Factors of care during pregnancy,

screenings

Attila Molvarec, MD, PhD

1st Department of Obstetrics and Gynecology

Semmelweis University, Budapest, Hungary

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

Prenatal care

Contents:

• Preconceptional care

• Prompt diagnosis of pregnancy

• Initial presentation for pregnancy care

• Follow-up prenatal visits

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

Diagnosis of pregnancy: ultrasonography

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

Recommended components of the initial

prenatal care visit (ACOG)

• Risk assessment to 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

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 rule to 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

Determination of fetal age: ultrasonography in the

first trimester – crown-rump length (CRL)

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

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

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

Hegar and Piskacek sign

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

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)

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

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)

Leopold maneuvers

Zangemeister maneuver

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

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)

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

Subsequent laboratory tests

• Complete blood count: each trimester

• Irregular antibody screening: 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 diabetes screening (WHO): 75 g oral glucose tolerance test (OGTT) at 24-28 weeks

• Urine sediment or culture for 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)

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)

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)

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

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

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/day is

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 protein are

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

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 mg for erythropoiesis), of which nearly all is used after midpregnancy

• At least 30 mg of ferrous iron supplement should be given daily from the second trimester, which amount is contained in most prenatal vitamins

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)

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

Recommended daily dietary allowances

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

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)

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

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)

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

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 A1C to compute risks for major congenital anomalies)

• General physical, gynecological, dental examination