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Question 1Antepartum Care

Using Naegele's rule, how is the estimated due date calculated from the last menstrual period?

  1. Subtract 3 months and add 7 days to the first day of the LMP Correct answer.
  2. Add 10 months and add 14 days to the first day of the LMP
  3. Subtract 7 days and add 3 months to the last day of the LMP
  4. Add 9 months and subtract 7 days from the last day of the LMP

Explanation

Naegele's rule estimates the due date from the first day of the last menstrual period by subtracting 3 months, adding 7 days, and advancing 1 year. It assumes a 28-day cycle with ovulation on day 14.

Question 2Antepartum Care

At what gestational age is routine screening for gestational diabetes performed in a woman with no prior diagnosis?

  1. 16 to 18 weeks
  2. 24 to 28 weeks Correct answer.
  3. 32 to 34 weeks
  4. 20 to 22 weeks

Explanation

Routine screening with a glucose challenge test is performed at 24 to 28 weeks, when insulin resistance from placental hormones is near its peak. Women with major risk factors may be screened earlier in pregnancy.

Question 3Antepartum Care

In a first pregnancy, a woman typically first perceives fetal movement at which gestational age?

  1. 22 to 24 weeks
  2. 12 to 14 weeks
  3. 18 to 20 weeks Correct answer.
  4. 26 to 28 weeks

Explanation

Quickening is usually appreciated at about 18 to 20 weeks in a first pregnancy and somewhat earlier in subsequent pregnancies. Perception before 16 weeks is uncommon.

Question 4Antepartum Care

Tdap vaccination is recommended during each pregnancy within which gestational window?

  1. 37 to 40 weeks
  2. 8 to 12 weeks
  3. 18 to 24 weeks
  4. 27 to 36 weeks Correct answer.

Explanation

A dose of Tdap is given in every pregnancy, ideally between 27 and 36 weeks, so that maternal antibody is transferred across the placenta before birth.

Question 5Antepartum Care

Which statement about inactivated influenza vaccination during pregnancy is correct?

  1. The live attenuated vaccine is preferred after 20 weeks
  2. It is recommended in any trimester during influenza season Correct answer.
  3. It is not recommended during pregnancy
  4. It is given only after the first trimester

Explanation

Inactivated influenza vaccine is recommended for all pregnant women in any trimester when influenza is circulating. The live attenuated intranasal vaccine is contraindicated in pregnancy.

Question 6Antepartum Care

Which food should be avoided during pregnancy because of the risk of listeriosis?

  1. Washed fresh fruit
  2. Unpasteurized soft cheese Correct answer.
  3. Well-cooked chicken
  4. Pasteurized yogurt

Explanation

Listeria monocytogenes survives refrigeration and contaminates unpasteurized dairy products and ready-to-eat foods. Infection can cause fetal loss, preterm birth, or neonatal sepsis.

Question 7Antepartum Care

For an uncomplicated pregnancy, the standard visit schedule is every 4 weeks until 28 weeks, then:

  1. Every 3 weeks until 38 weeks, then weekly
  2. Monthly until 36 weeks, then weekly
  3. Every 2 weeks until 36 weeks, then weekly Correct answer.
  4. Every week until 36 weeks, then every 2 weeks

Explanation

Routine prenatal visits occur every 4 weeks until 28 weeks, every 2 weeks until 36 weeks, and weekly from 36 weeks until delivery.

Question 8Antepartum Care

What daily folic acid dose is recommended before conception and in early pregnancy for a woman at average risk of a neural tube defect?

  1. 400 mcg Correct answer.
  2. 1 mg
  3. 2 mg
  4. 4 mg

Explanation

Women at average risk should take 400 mcg of folic acid daily, beginning at least 1 month before conception and continuing through the first trimester. Higher doses are reserved for women with specific risk factors.

Question 9Antepartum Care

A woman is currently pregnant. She had one term delivery at 39 weeks and one spontaneous abortion at 10 weeks. Using GTPAL, how is she classified?

  1. G2 P1011
  2. G3 P1111
  3. G3 P1001
  4. G3 P1011 Correct answer.

Explanation

GTPAL counts all pregnancies including the current one, then lists term, preterm, abortions, and living children separately. This woman has three pregnancies, one term birth, no preterm births, one abortion, and one living child.

Question 10Antepartum Care

When should an Rh-negative, unsensitized pregnant woman receive Rho(D) immune globulin?

  1. At 28 weeks' gestation and within 72 hours after delivery of an Rh-positive infant Correct answer.
  2. Only if the newborn is found to be Rh-negative
  3. At 20 weeks' gestation and again at 32 weeks
  4. At 36 weeks' gestation only

Explanation

Prophylaxis is given at about 28 weeks and within 72 hours of delivery when the infant is Rh-positive. Additional doses are indicated after events such as amniocentesis, bleeding, or abdominal trauma.

Question 11Antepartum Care

At what gestational age is the routine rectovaginal culture for group B Streptococcus collected?

  1. 20 to 24 weeks
  2. 32 to 34 weeks
  3. 36 0/7 to 37 6/7 weeks Correct answer.
  4. 39 to 40 weeks

Explanation

GBS cultures are obtained at 36 0/7 to 37 6/7 weeks so that the result is close enough to delivery to predict intrapartum colonization. Cultures from earlier in pregnancy do not reliably reflect status at birth.

Question 12Antepartum Care

Which ultrasound measurement provides the most accurate estimate of gestational age in early pregnancy?

  1. Femur length at 36 weeks
  2. Crown-rump length at 8 weeks Correct answer.
  3. Biparietal diameter at 32 weeks
  4. Fundal height at 24 weeks

Explanation

First-trimester crown-rump length is the most accurate dating measure because biologic variation in size is minimal before 14 weeks. Later biometry carries progressively wider prediction intervals.

Question 13Antepartum Care

Which medication is considered first-line pharmacologic therapy for nausea and vomiting of pregnancy?

  1. Doxylamine with pyridoxine Correct answer.
  2. Ondansetron
  3. Metoclopramide
  4. Promethazine

Explanation

The doxylamine-pyridoxine combination is the only FDA-approved first-line pharmacologic treatment for nausea and vomiting of pregnancy. Other agents are added when symptoms persist despite first-line therapy.

Question 14Antepartum Care

Approximately how much elemental iron per day is recommended during pregnancy?

  1. 100 mg
  2. 27 mg Correct answer.
  3. 65 mg
  4. 10 mg

Explanation

Pregnancy raises iron requirements to about 27 mg per day to support the expanded maternal red cell mass and fetal iron stores. This is why a prenatal vitamin with iron is routinely recommended.

Question 15Antepartum Care

Which factor most strongly increases a woman's risk of ectopic pregnancy?

  1. Grand multiparity
  2. Obesity
  3. Prior tubal surgery Correct answer.
  4. Maternal age over 30 years

Explanation

Prior tubal surgery, prior ectopic pregnancy, and tubal infection damage the fallopian tube and impair embryo transport. Parity, age, and body mass index are much weaker predictors.

Question 16Antepartum Care

Beginning at about what gestational age does fundal height in centimeters correlate with gestational age in weeks?

  1. 20 weeks Correct answer.
  2. 12 weeks
  3. 28 weeks
  4. 32 weeks

Explanation

From roughly 20 weeks until 36 weeks, the fundal height in centimeters approximates gestational age in weeks. A discrepancy of 3 cm or more warrants further evaluation.

Question 17Antepartum Care

How many additional calories per day are recommended during the second trimester of a singleton pregnancy?

  1. 340 kcal Correct answer.
  2. 450 kcal
  3. 700 kcal
  4. 100 kcal

Explanation

An additional 340 kcal per day is recommended in the second trimester and about 450 kcal per day in the third. The first trimester requires no additional calories.

Question 18Antepartum Care

Cell-free DNA screening for fetal aneuploidy can be performed beginning at what gestational age?

  1. 15 weeks
  2. 24 weeks
  3. 6 weeks
  4. 10 weeks Correct answer.

Explanation

Cell-free DNA screening may be offered from 10 weeks, when the fetal fraction in maternal plasma is sufficient for analysis. A low fetal fraction or an abnormal result requires diagnostic testing.

Question 19Antepartum Care

Which statement about asymptomatic bacteriuria in pregnancy is correct?

  1. It resolves spontaneously in most women
  2. It is screened for at the first prenatal visit and treated Correct answer.
  3. It is screened for only in the third trimester
  4. It does not require treatment

Explanation

Asymptomatic bacteriuria affects a small but meaningful proportion of pregnant women and, if untreated, predisposes to pyelonephritis and preterm birth. A urine culture is obtained at the first prenatal visit and positive results are treated.

Question 20Antepartum Care

Angiotensin-converting enzyme inhibitors used during the second and third trimesters are associated with which fetal effect?

  1. Fetal renal failure with oligohydramnios Correct answer.
  2. Neural tube defects
  3. Limb reduction defects
  4. Ebstein cardiac anomaly

Explanation

ACE inhibitors impair fetal renal development, producing renal tubular dysplasia, oligohydramnios, and skull hypoplasia when exposure occurs after organogenesis. They are discontinued as soon as pregnancy is recognized.

Question 21Antepartum Care

In a woman at high risk for preeclampsia, when should low-dose aspirin prophylaxis be started?

  1. After 28 weeks
  2. Only if blood pressure exceeds 140/90 mm Hg
  3. At the onset of the third trimester
  4. Between 12 and 16 weeks Correct answer.

Explanation

Low-dose aspirin (81 mg daily) is recommended for high-risk women, begun between 12 and 16 weeks, ideally before 16 weeks. Starting later reduces the benefit for prevention.

Question 22Antepartum Care

Which finding best supports a diagnosis of hyperemesis gravidarum rather than ordinary nausea and vomiting of pregnancy?

  1. Weight loss over 5% of prepregnancy weight with dehydration Correct answer.
  2. Mild ketonuria with normal electrolyte levels
  3. Vomiting twice weekly during the first trimester
  4. Nausea that is relieved by eating dry crackers

Explanation

Hyperemesis gravidarum is distinguished by weight loss exceeding 5% of prepregnancy weight together with dehydration, ketonuria, and electrolyte or acid-base disturbance. Uncomplicated nausea and vomiting does not produce these systemic findings.

Question 23Antepartum Care

In a twin pregnancy, chorionicity is most reliably determined by ultrasound at which time?

  1. During the third trimester
  2. Only after delivery
  3. Before 14 weeks' gestation Correct answer.
  4. At the anatomy scan near 20 weeks

Explanation

Chorionicity is best assigned before 14 weeks by assessing membrane thickness and the lambda or T sign at the placental insertion. Later in gestation these signs become less reliable and management decisions depend on the early assessment.

Question 24Antepartum Care

A woman at 20 weeks' gestation has a cervical length of 20 mm on transvaginal ultrasound. Which management has been shown to reduce the risk of preterm birth?

  1. Routine antibiotic prophylaxis
  2. Strict bed rest until 36 weeks
  3. Vaginal progesterone Correct answer.
  4. Cervical cerclage for all such women

Explanation

A cervical length of 25 mm or less before 24 weeks identifies increased preterm birth risk, and vaginal progesterone reduces that risk in this group. Cerclage is reserved for women with specific prior pregnancy histories.

Question 25Antepartum Care

Which finding is most characteristic of a complete hydatidiform mole?

  1. Fetal heart tones auscultated in the second trimester
  2. A vesicular snowstorm pattern on ultrasound with markedly elevated hCG Correct answer.
  3. Severe oligohydramnios with growth restriction
  4. A normal hCG level with an empty gestational sac

Explanation

A complete mole shows a vesicular, snowstorm appearance with no fetal parts and hCG levels far above those expected for dates. Partial moles may contain fetal tissue and are typically triploid.

Question 26Antepartum Care

A woman's last menstrual period began on April 10. Using Naegele's rule, what is her estimated date of delivery?

  1. January 17 of the following year Correct answer.
  2. January 10 of the following year
  3. January 3 of the following year
  4. February 17 of the following year

Explanation

Naegele's rule estimates delivery by subtracting 3 months from the first day of the last menstrual period and adding 7 days. April 10 minus 3 months is January 10, and adding 7 days gives January 17.

Question 27Antepartum Care

A nulliparous woman asks when she will likely first feel fetal movement. At what gestational age does quickening typically become perceptible in a first pregnancy?

  1. 22 to 24 weeks
  2. 15 to 17 weeks
  3. 12 to 14 weeks
  4. 18 to 20 weeks Correct answer.

Explanation

First-time mothers generally perceive fetal movement between 18 and 20 weeks, while women who have been pregnant before often notice it 2 weeks earlier. Perception before 16 weeks is uncommon in a first pregnancy.

Question 28Antepartum Care

On bimanual examination, the uterine fundus first becomes palpable at the level of the symphysis pubis at approximately which gestational age?

  1. 12 weeks Correct answer.
  2. 8 weeks
  3. 16 weeks
  4. 20 weeks

Explanation

The uterus remains within the pelvis until about 12 weeks, when the fundus can be felt at the symphysis pubis. It reaches the umbilicus at roughly 20 weeks, providing a rough clinical marker of gestational age.

Question 29Antepartum Care

Which vaccine is recommended during every pregnancy, ideally between 27 and 36 weeks' gestation, regardless of prior vaccination history?

  1. Influenza vaccine
  2. Tdap vaccine Correct answer.
  3. Varicella vaccine
  4. MMR vaccine

Explanation

Tdap is given in each pregnancy during the 27-to-36-week window so that maternal antibody is transferred to the newborn. Live vaccines such as MMR and varicella are contraindicated in pregnancy.

Question 30Antepartum Care

For a pregnant woman at average risk, at what gestational age is routine screening for gestational diabetes recommended?

  1. 8 to 12 weeks
  2. 16 to 20 weeks
  3. 32 to 34 weeks
  4. 24 to 28 weeks Correct answer.

Explanation

Universal glucose screening is performed at 24 to 28 weeks, when placental hormones that cause insulin resistance are sufficiently elevated to unmask the disorder. Women with risk factors may also be screened earlier in pregnancy.

Question 31Antepartum Care

What daily caffeine intake is generally considered an acceptable upper limit during pregnancy?

  1. 100 mg per day
  2. 500 mg per day
  3. 200 mg per day Correct answer.
  4. 300 mg per day

Explanation

Guidance supports limiting caffeine to about 200 mg per day in pregnancy, roughly the amount in a 12-ounce cup of coffee. Higher intake has been associated with increased risk of miscarriage and low birth weight.

Question 32Antepartum Care

Which statement best reflects current guidance on alcohol consumption during pregnancy?

  1. One drink per week is acceptable after 20 weeks
  2. Beer is safer than distilled spirits
  3. Binge drinking is only a concern in the first trimester
  4. No amount of alcohol has been shown to be safe Correct answer.

Explanation

Because no threshold for fetal harm has been established, complete abstinence is recommended throughout pregnancy. Alcohol exposure can produce fetal alcohol spectrum disorders with lifelong neurodevelopmental effects.

Question 33Antepartum Care

A 34-year-old woman at 11 weeks' gestation requests prenatal diagnostic testing because her first child has a known single-gene disorder. Which procedure can be offered at this gestational age?

  1. Cordocentesis
  2. Maternal serum quad screen
  3. Chorionic villus sampling Correct answer.
  4. Amniocentesis

Explanation

Chorionic villus sampling is performed between 10 and 13 weeks and yields fetal tissue for genetic diagnosis. Amniocentesis is generally delayed until about 15 weeks to reduce procedure-related loss and amniotic fluid leak.

Question 34Antepartum Care

Maternal serum alpha-fetoprotein screening for open neural tube defects is optimally collected at which gestational age?

  1. 16 to 18 weeks Correct answer.
  2. 10 to 12 weeks
  3. 30 to 32 weeks
  4. 24 to 26 weeks

Explanation

Alpha-fetoprotein screening is best obtained between 15 and 20 weeks, with 16 to 18 weeks being optimal. Results are interpreted in multiples of the median and adjusted for maternal weight, race, and diabetes status.

Question 35Antepartum Care

What total weight gain is recommended for a woman with a normal prepregnancy body mass index who is carrying a singleton pregnancy?

  1. 7 to 11.5 kg
  2. 11.5 to 16 kg Correct answer.
  3. 17 to 22 kg
  4. 5 to 9 kg

Explanation

For a normal prepregnancy BMI, the recommended total gain is roughly 11.5 to 16 kg, corresponding to about 25 to 35 pounds. Recommended ranges are higher for underweight women and lower for overweight and obese women.

Question 36Antepartum Care

Which practice most reduces a pregnant woman's risk of acquiring toxoplasmosis?

  1. Avoiding unpasteurized soft cheese and deli meats
  2. Avoiding contact with young children
  3. Avoiding undercooked meat and wearing gloves when handling cat litter Correct answer.
  4. Rinsing raw produce in vinegar before eating

Explanation

Toxoplasma is transmitted through tissue cysts in undercooked meat and oocysts shed in cat feces and contaminated soil. Cooking meat thoroughly and using gloves or delegating litter box care are the key preventive steps.

Question 37Antepartum Care

A woman with severe nodulocystic acne has been taking oral isotretinoin and reports a positive home pregnancy test this week. What is the most appropriate action?

  1. Reduce the dose until 12 weeks
  2. Switch to topical tretinoin
  3. Stop the drug and arrange counseling Correct answer.
  4. Reassure her that risk is minimal

Explanation

Isotretinoin is a potent teratogen associated with craniofacial, cardiac, and central nervous system malformations, so it must be stopped as soon as pregnancy is recognized. Urgent counseling should address exposure risk and prenatal diagnostic options.

Question 38Antepartum Care

At 28 weeks' gestation, which hemoglobin concentration meets the diagnostic threshold for anemia in pregnancy?

  1. 11.5 g/dL
  2. 13.5 g/dL
  3. 9.5 g/dL Correct answer.
  4. 12.5 g/dL

Explanation

Anemia in pregnancy is defined as a hemoglobin below 11.0 g/dL in the first and third trimesters, reflecting plasma volume expansion. A value of 9.5 g/dL therefore meets the threshold and warrants evaluation for iron deficiency.

Question 39Antepartum Care

A woman with primary hypothyroidism treated with levothyroxine has a positive pregnancy test at 6 weeks. What management is recommended?

  1. Stop levothyroxine until the second trimester
  2. Replace levothyroxine with methimazole
  3. Continue the current prepregnancy dose and recheck TSH at the 20-week visit
  4. Increase the dose about 20 to 30 percent and recheck TSH in 4 weeks Correct answer.

Explanation

Thyroid hormone requirements rise early in pregnancy because of increased thyroid-binding globulin and placental transfer, so most women need a 20 to 30 percent dose increase. TSH should be rechecked about every 4 weeks during the first half of pregnancy.

Question 40Antepartum Care

A woman at 32 weeks' gestation becomes diaphoretic and lightheaded while lying flat on her back during a procedure. What is the best initial action?

  1. Elevate the head of the bed
  2. Give a rapid intravenous fluid bolus
  3. Reposition her into the left lateral position Correct answer.
  4. Prepare for emergency cesarean delivery

Explanation

In the supine position the gravid uterus compresses the inferior vena cava, reducing venous return and cardiac output. Turning the patient to the left lateral position displaces the uterus and reliably corrects the hypotension.

Question 41Antepartum Care

How is routine prenatal screening for human immunodeficiency virus best described?

  1. Offered to all pregnant women unless they decline Correct answer.
  2. Required by law only for women in high-risk groups
  3. Deferred until the third trimester
  4. Performed only when the woman requests it

Explanation

Screening uses an opt-out approach in which all pregnant women are offered testing with the right to refuse. Early identification allows antiretroviral therapy that markedly reduces vertical transmission.

Question 42Antepartum Care

Nuchal translucency measurement for first-trimester aneuploidy screening is performed within which gestational window?

  1. 10 to 12 weeks
  2. 18 to 22 weeks
  3. 15 to 17 weeks
  4. 11 to 13 6/7 weeks Correct answer.

Explanation

The nuchal translucency is measured when the crown-rump length corresponds to 11 to 13 6/7 weeks. Outside this window the fluid collection is either not yet developed or has resolved, making the measurement uninterpretable.

Question 43Antepartum Care

A quad screen at 17 weeks shows an alpha-fetoprotein level of 0.5 multiples of the median with the other analytes within normal limits. This result most increases the risk of which condition?

  1. Gastroschisis
  2. Open neural tube defect
  3. Down syndrome Correct answer.
  4. Normal variation needing no follow-up

Explanation

Low alpha-fetoprotein is associated with an increased risk of fetal aneuploidy, particularly trisomy 21, and prompts offering of diagnostic testing. Elevated alpha-fetoprotein, by contrast, raises concern for open neural tube or abdominal wall defects.

Question 44Antepartum Care

A woman with about 6 weeks of amenorrhea has an empty uterine cavity on transvaginal ultrasound and a serum beta-hCG of 4,500 mIU/mL. What is the most appropriate next step?

  1. Reassure her and repeat the ultrasound in 4 weeks
  2. Evaluate for ectopic pregnancy with serial hCG and repeat imaging Correct answer.
  3. Administer methotrexate immediately
  4. Proceed with endometrial sampling

Explanation

An intrauterine gestational sac is expected on transvaginal ultrasound once hCG exceeds roughly 3,500 mIU/mL, so an empty uterus at this level is concerning for an abnormal or ectopic pregnancy. Serial hCG measurements and repeat imaging establish the diagnosis before treatment decisions are made.

Question 45Intrapartum Care

Which set of findings defines a Category I fetal heart rate tracing?

  1. Baseline 120–150 bpm with marked variability and prolonged decelerations
  2. Baseline 100–110 bpm with minimal variability and recurrent variable decelerations
  3. Baseline 160–170 bpm with absent variability and recurrent late decelerations
  4. Baseline 110–160 bpm with moderate variability and no late decelerations Correct answer.

Explanation

A Category I tracing requires a baseline of 110–160 bpm, moderate variability, and no late or variable decelerations; early decelerations and accelerations may be present. Any tracing with absent variability, recurrent late or variable decelerations, or an abnormal baseline falls outside Category I.

Question 46Intrapartum Care

Active-phase arrest of labor is diagnosed when there is no cervical change for at least 4 hours despite adequate contractions, with dilation at or beyond which threshold?

  1. 10 cm
  2. 3 cm
  3. 6 cm Correct answer.
  4. 8 cm

Explanation

Contemporary definitions set the start of the active phase at 6 cm, and arrest is diagnosed when there is no cervical change for 4 hours with adequate contractions or 6 hours with inadequate contractions at or beyond 6 cm. Slower progress before 6 cm is considered normal latent-phase labor.

Question 47Intrapartum Care

After the head is delivered and shoulder dystocia is recognized, which maneuver is performed first?

  1. Delivery of the posterior arm followed by the Zavanelli maneuver
  2. Symphysiotomy performed under general anesthesia
  3. McRoberts maneuver with suprapubic pressure Correct answer.
  4. Fundal pressure applied while the head is flexed

Explanation

McRobverts maneuver (hyperflexion of the maternal hips) combined with suprapubic pressure is the recommended first-line approach because it enlarges the pelvic outlet and rotates the anterior shoulder. More invasive maneuvers are reserved for failure of these initial steps.

Question 48Intrapartum Care

Umbilical cord prolapse is identified during labor. What is the immediate priority?

  1. Rupture remaining membranes to relieve cord compression
  2. Immediate cesarean under general anesthesia with a full prep
  3. Start high-dose oxytocin infusion to hasten vaginal delivery
  4. Elevate the presenting part and use knee-chest position Correct answer.

Explanation

The first action is to relieve pressure on the cord by elevating the presenting part manually or with filling the bladder and placing the woman in knee-chest or Trendelenburg position, while preparations are made for expeditious delivery. Oxytocin and membrane rupture would worsen cord compression.

Question 49Intrapartum Care

Which statement about thick meconium-stained amniotic fluid is correct?

  1. Amnioinfusion during labor reliably prevents meconium aspiration syndrome
  2. Meconium staining is a definitive sign of fetal acidemia at birth
  3. Thick meconium warrants a skilled neonatal resuscitation team at delivery Correct answer.
  4. Routine endotracheal suctioning is indicated for every vigorous newborn with meconium

Explanation

Thick meconium increases the risk of meconium aspiration syndrome, so a team skilled in neonatal resuscitation should be present at delivery. Routine intrapartum suctioning, routine intubation of vigorous infants, and prophylactic amnioinfusion are not recommended.

Question 50Intrapartum Care

Which factor most strongly increases the probability of a successful trial of labor after cesarean?

  1. Induction of labor
  2. A prior cesarean performed for dystocia
  3. Maternal obesity
  4. A prior vaginal birth Correct answer.

Explanation

A history of any prior vaginal birth, including a vaginal birth after cesarean, is the strongest predictor of VBAC success. Prior cesarean for dystocia, obesity, and induction all lower the likelihood of success.