Prenatal Care Practice Questions

Q: Which of the following abdominal palpation findings is characteristic at 18 weeks of gestation?

External ballottement. **Explanation:** The correct answer is **External ballottement**. **1. Why External Ballottement is correct:** External ballottement is a clinical sign typically elicited between **16 and 20 weeks** of gestation. At 18 weeks, the volume of amniotic fluid is relatively large compared to the size of the fetus. When the clinician applies a sudden tap or impulse to the uterus through the abdominal wall, the fetus floats away in the liquor and then strikes back against the examining fingers. This "rebound" sensation is a classic finding of mid-trimester pregnancy. **2. Analysis of Incorrect Options:** * **Internal ballottement:** While similar in principle, this is performed via the vaginal route (digital examination) and is typically felt earlier, starting around **14 weeks**. * **Fetal head grip (Leopold’s Fourth Maneuver):** This maneuver is used to determine the engagement of the head. It is only performed in the **third trimester** (usually after 36 weeks) when the presenting part is well-defined and occupies the lower pole of the uterus. * **Palmer’s sign:** This refers to rhythmic, regular contractions of the uterus felt during pelvic examination in early pregnancy. It is characteristic of the **first trimester** (usually between 4–8 weeks). **3. High-Yield Clinical Pearls for NEET-PG:** * **Quickening:** Usually felt at **18 weeks** in primigravida and **16 weeks** in multigravida. * **Fundal Height at 18 weeks:** The fundus is located roughly midway between the pubic symphysis and the umbilicus (at 20 weeks, it reaches the umbilicus). * **Amniotic Fluid:** External ballottement disappears in late pregnancy as the fetus grows larger and the relative amount of liquor decreases, making the fetus "snug" in the uterus. * **Differential:** External ballottement can also be felt in cases of large subserosal fibroids or ovarian cysts with ascites, but in the context of pregnancy, it is a "probable" sign.

Q: Which vaccine is contraindicated during pregnancy?

Varicella. **Explanation:** The fundamental principle in prenatal vaccination is the distinction between **Inactivated/Recombinant vaccines** (generally safe) and **Live-Attenuated vaccines** (generally contraindicated). **Why Varicella is the correct answer:** Varicella is a **live-attenuated virus vaccine**. It is contraindicated during pregnancy because of the theoretical risk of vertical transmission of the vaccine virus to the fetus, which could potentially lead to **Congenital Varicella Syndrome**. According to standard guidelines, women should be advised to avoid pregnancy for at least one month after receiving the varicella vaccine. **Analysis of Incorrect Options:** * **Hepatitis A & B:** These are **inactivated** (Hep A) or **recombinant** (Hep B) vaccines. They are not contraindicated and can be administered if the pregnant woman is at high risk for infection. * **Rabies:** This is a **killed/inactivated** vaccine. Because rabies is a fatal disease, the vaccine is administered as post-exposure prophylaxis even during pregnancy; the benefits far outweigh any theoretical risks. **NEET-PG High-Yield Pearls:** * **Absolute Contraindications (Live Vaccines):** MMR (Measles, Mumps, Rubella), Varicella, BCG, Yellow Fever, and Oral Polio (OPV). * **The "Rule of Rubella":** If a pregnant woman is found to be non-immune to Rubella, the vaccine should be given in the **immediate postpartum period**, never during pregnancy. * **Recommended Vaccines:** Tdap (Tetanus, Diphtheria, and Pertussis) is recommended during every pregnancy (ideally between 27–36 weeks) to provide passive immunity to the neonate. * **Influenza:** The inactivated injectable flu vaccine is safe and recommended in any trimester during flu season.

Q: All of the following can be used to determine a chromosome analysis of the fetus except?

Fetal umbilical Doppler velocimetry. **Explanation:** The core concept here is distinguishing between **invasive diagnostic procedures** (which obtain fetal cells for genetic analysis) and **non-invasive screening/surveillance tools** (which assess fetal well-being and hemodynamics). **Why Option D is correct:** **Fetal umbilical Doppler velocimetry** is a non-invasive ultrasound technique used to assess placental resistance and fetal blood flow. It measures the ratio of systolic to diastolic flow in the umbilical artery. It is used to monitor fetuses with Intrauterine Growth Restriction (IUGR) or Rh isoimmunization, but it **cannot** provide genetic material or cells for chromosomal analysis (karyotyping). **Why the other options are incorrect:** * **A. Amniocentesis:** The gold standard for prenatal diagnosis. It involves aspirating amniotic fluid containing fetal desquamated cells (amniocytes), which are cultured for karyotyping. Usually performed at 15–20 weeks. * **B. Chorionic Villus Sampling (CVS):** Involves taking a biopsy of the placental trophoblastic tissue. It provides fetal cells for rapid chromosomal analysis and can be performed earlier than amniocentesis (10–13 weeks). * **C. Percutaneous Umbilical Blood Sampling (PUBS):** Also known as Cordocentesis. It involves ultrasound-guided aspiration of fetal blood directly from the umbilical vein. It provides the fastest karyotype results (within 48–72 hours) via lymphocyte culture. **High-Yield Clinical Pearls for NEET-PG:** * **Earliest Diagnostic Test:** CVS (10–13 weeks). * **Most Common Diagnostic Test:** Amniocentesis. * **Fastest Karyotype:** PUBS/Cordocentesis. * **Risk of Limb Reduction Defects:** Associated with CVS if performed before 9–10 weeks. * **Doppler Significance:** "Absent or Reversed End-Diastolic Velocity" (AEDV/REDV) on umbilical Doppler is a critical sign of fetal compromise requiring urgent intervention.

Q: All of the following disorders can be diagnosed antenatally except?

Pernicious anaemia. **Explanation:** The core concept behind this question lies in the distinction between **genetic (inherited) disorders** and **acquired nutritional deficiencies**. **Why Pernicious Anaemia is the correct answer:** Pernicious anaemia is an **autoimmune condition** characterized by the production of antibodies against gastric parietal cells or intrinsic factor, leading to Vitamin B12 deficiency. It is an acquired condition that typically manifests in later adulthood. Since it is not caused by a specific, single-gene mutation detectable in fetal DNA, it cannot be diagnosed antenatally through standard prenatal screening or invasive testing (like CVS or Amniocentesis). **Why the other options are incorrect:** * **Hemophilia (A & B):** These are X-linked recessive bleeding disorders. They can be diagnosed antenatally by identifying the specific mutation in the F8 or F9 gene via Chorionic Villus Sampling (CVS). * **Thalassemia:** This is an autosomal recessive hemoglobinopathy. It is routinely diagnosed antenatally using DNA analysis of fetal tissue to look for alpha or beta-globin gene mutations. * **Sickle Cell Anemia:** Similar to Thalassemia, this is a point mutation in the HBB gene. It is easily detectable through molecular genetic testing of fetal cells. **NEET-PG High-Yield Pearls:** * **Prenatal Diagnostic Tools:** Genetic disorders (Options A, B, C) are diagnosed using **CVS (10–13 weeks)** or **Amniocentesis (15–20 weeks)**. * **Most Common Indication:** The most common indication for invasive prenatal diagnosis worldwide is advanced maternal age, but in India, it is frequently performed for **Thalassemia major** screening. * **Karyotyping vs. DNA Analysis:** Karyotyping is used for chromosomal anomalies (e.g., Down Syndrome), while DNA analysis (PCR) is used for Mendelian disorders like Hemophilia and Thalassemia.

Q: What is the ideal time for screening of blood sugar for diabetes in a pregnant female?

24-28 weeks. **Explanation:** The correct answer is **C. 24-28 weeks.** **Why 24-28 weeks is the ideal time:** Pregnancy is a state of progressive insulin resistance. This is primarily due to the secretion of **diabetogenic hormones** by the placenta, most notably **Human Placental Lactogen (hPL)**, along with cortisol, prolactin, and progesterone. These hormones peak during the late second and early third trimesters. Screening at 24-28 weeks captures the period when insulin resistance becomes significant enough to manifest as Gestational Diabetes Mellitus (GDM) in susceptible women. **Analysis of Incorrect Options:** * **A, B, & D (12-24 weeks):** While screening can be done earlier, it is generally reserved for high-risk patients (e.g., history of GDM, obesity, or PCOS). In a low-risk or routine screening scenario, testing before 24 weeks may yield a false negative because the physiological insulin resistance has not yet reached its peak. **High-Yield Clinical Pearls for NEET-PG:** * **DIPSI Guidelines (India):** A single-step 75g Oral Glucose Tolerance Test (OGTT) is recommended. A 2-hour plasma glucose value **≥140 mg/dL** is diagnostic of GDM, regardless of the last meal. * **Early Screening:** If a woman has high-risk factors, screen at the **first prenatal visit**. If negative, repeat the test at 24-28 weeks. * **Postpartum Follow-up:** Women with GDM should be screened for Type 2 Diabetes **6-12 weeks postpartum** using a 75g OGTT. * **Most common fetal complication:** Fetal macrosomia (due to fetal hyperinsulinemia). * **Most common fetal malformation in Pre-gestational Diabetes:** Caudal Regression Syndrome (though Ventricular Septal Defect is the most common cardiac defect).

Q: What is the most specific marker for neural tube defects?

Acetylcholinesterase. **Explanation:** The diagnosis of Neural Tube Defects (NTDs) involves a sequential screening and diagnostic process. **Why Acetylcholinesterase (AChE) is the correct answer:** While Alpha-fetoprotein (AFP) is the primary screening tool, **Acetylcholinesterase (AChE)** is the most specific biochemical marker. AChE is an enzyme found in high concentrations within neural tissue. In cases of open NTDs (like anencephaly or open spina bifida), the fetal cerebrospinal fluid—which contains this enzyme—leaks directly into the amniotic fluid. Detecting AChE via amniocentesis (using gel electrophoresis) confirms the presence of exposed neural tissue, effectively ruling out false positives caused by other conditions. **Analysis of Incorrect Options:** * **Alpha-fetoprotein (AFP):** This is a highly **sensitive** screening marker but lacks specificity. Elevated levels can occur in multiple gestations, omphalocele, gastroschisis, pilonidal cysts, or even due to incorrect gestational dating. * **Pseudocholinesterase:** This enzyme is found in the liver and serum but is not specific to neural tissue. It does not serve as a diagnostic marker for NTDs. * **Inhibin:** Inhibin-A is a component of the "Quadruple Screen" used primarily to screen for **Down Syndrome** (where it is elevated) and Trisomy 18, not NTDs. **NEET-PG High-Yield Pearls:** * **Best Screening Test:** Maternal Serum Alpha-fetoprotein (MSAFP) at 15–20 weeks. * **Best Diagnostic Investigation:** Targeted Level II Ultrasound (the "Gold Standard" in modern practice). * **Lemon Sign & Banana Sign:** Classic ultrasound findings associated with Spina Bifida. * **Prevention:** 400 mcg of Folic Acid daily (pre-conceptionally) reduces NTD risk by 70%; 4 mg is required for women with a previous affected pregnancy.

Q: Gender of the fetus is first evident by what gestational age in weeks?

12 weeks. **Explanation:** The determination of fetal gender is a chronological process involving genetic, gonadal, and phenotypic stages. While genetic sex is determined at fertilization, the external genitalia remain undifferentiated until approximately the 7th to 8th week. **Why 12 weeks is correct:** By the **12th week of gestation**, the external genitalia have developed sufficiently to be morphologically distinguishable. In males, the phallus elongates to form the penis and the labioscrotal swellings fuse to form the scrotum. In females, the phallus becomes the clitoris and the swellings remain unfused to form the labia. While ultrasound accuracy increases significantly by 16 weeks, the **first evidence** of distinct phenotypic gender occurs at 12 weeks. **Analysis of Incorrect Options:** * **6 weeks:** At this stage, the embryo is in the "indifferent stage." The genital tubercle and urogenital folds are present but appear identical in both sexes. * **8 weeks:** Differentiation of the internal gonads (testes or ovaries) begins under the influence of the SRY gene, but external phenotypic differences are not yet evident to the naked eye or standard imaging. * **16 weeks:** This is the "ideal" time for a highly accurate sonographic gender determination (mid-trimester scan), but it is not the *first* time gender is evident. **NEET-PG High-Yield Pearls:** * **Genetic Sex:** Determined at fertilization (0 weeks). * **Gonadal Differentiation:** Starts at 7–8 weeks (Testes develop earlier than ovaries). * **Phenotypic Gender:** Evident by 12 weeks. * **Ultrasound "Sagittal Sign":** Used in the first trimester (11–14 weeks) to predict sex by the angle of the genital tubercle. * **Legal Note:** Under the **PCPNDT Act** in India, prenatal sex determination is illegal and punishable.

Q: At what period of gestation is a detailed survey for fetal anomalies typically performed?

18-20 weeks. **Explanation:** The **Anomaly Scan** (also known as the Level II ultrasound or Mid-trimester morphology scan) is ideally performed between **18 and 20 weeks** of gestation. **Why 18-20 weeks is the correct answer:** At this gestational age, fetal organogenesis is complete, and the fetus has reached a size where the internal anatomy (especially the four-chamber heart, kidneys, and spine) can be visualized with high resolution. Additionally, the volume of amniotic fluid is relatively large compared to the fetus, providing an excellent acoustic window for detailed imaging. **Analysis of Incorrect Options:** * **12-14 weeks:** This is the window for the **NT (Nuchal Translucency) scan**. While major defects like anencephaly can be seen, the organs are too small for a "detailed" survey. * **14-16 weeks:** The heart and brain structures are still developing and are often too small for a definitive structural evaluation. * **16-18 weeks:** While some anomalies are visible, visualization of the cardiac outflow tracts and certain neural tube defects is less reliable than at 18-20 weeks. **High-Yield Clinical Pearls for NEET-PG:** * **Soft Markers:** The scan looks for markers like choroid plexus cysts, echogenic intracardiac focus (EIF), and single umbilical artery, which may indicate underlying chromosomal issues. * **TIFFA:** This scan is often referred to as **TIFFA** (Targeted Imaging for Fetal Anomalies). * **Legal Limit:** In India, under the MTP Act (Amendment 2021), the upper limit for termination of pregnancy for substantial fetal abnormalities is not restricted by a 24-week ceiling if approved by a Medical Board, making the 18-20 week window crucial for timely decision-making.

Question 1

All of the following statements about prenatal steroids are true except?

Accepted Answer

These can be given even in the presence of chorioamnionitis.

Answer

They cause a 50% reduction in respiratory distress syndrome and intraventricular hemorrhage.

Answer

These are advocated for mothers at risk of preterm delivery between 24-34 weeks of gestation.

Answer

These can be safely administered to mothers with hypertension or diabetes.

Question 2

Which of the following abdominal palpation findings is characteristic at 18 weeks of gestation?

Accepted Answer

External ballottement

Answer

Internal ballottement

Answer

Fetal head grip

Answer

Palmer's sign

Question 3

A 36-year-old woman with a long history of epilepsy is contemplating pregnancy and is concerned about the potential adverse effects of her anticonvulsant medications on her fetus. Which of the following statements regarding epilepsy and pregnancy is FALSE?

Accepted Answer

Phenytoin (Dilantin) is associated with a 1 to 2% risk of spina bifida.

Answer

The risk of structural anomalies in babies born to mothers with epilepsy is increased, even without anticonvulsant medication use.

Answer

Neurologists should attempt to wean epileptic women off their anticonvulsant medications prior to conception.

Answer

Folic acid supplementation can reduce the risk of congenital anomalies in fetuses of epileptic women taking anticonvulsants.

Question 4

Which vaccine is contraindicated during pregnancy?

Accepted Answer

Varicella

Answer

Hepatitis A

Answer

Hepatitis B

Answer

Rabies

Question 5

All of the following can be used to determine a chromosome analysis of the fetus except?

Accepted Answer

Fetal umbilical Doppler velocimetry

Answer

Amniocentesis

Answer

Chorionic villus sampling

Answer

Percutaneous umbilical blood sampling (PUBS)

Question 6

All of the following disorders can be diagnosed antenatally except?

Accepted Answer

Pernicious anaemia

Answer

Hemophilia

Answer

Thalassemia

Answer

Sickle cell anemia

Question 7

What is the ideal time for screening of blood sugar for diabetes in a pregnant female?

Accepted Answer

24-28 weeks

Answer

16-20 weeks

Answer

20-24 weeks

Answer

12-16 weeks

Question 8

What is the most specific marker for neural tube defects?

Accepted Answer

Acetylcholinesterase

Answer

Alpha fetoprotein

Answer

Pseudocholinesterase

Answer

Inhibin

Question 9

Gender of the fetus is first evident by what gestational age in weeks?

Accepted Answer

12 weeks

Answer

6 weeks

Answer

8 weeks

Answer

16 weeks

Question 10

At what period of gestation is a detailed survey for fetal anomalies typically performed?

Accepted Answer

18-20 weeks

Answer

12-14 weeks

Answer

14-16 weeks

Answer

16-18 weeks

Prenatal Care — MCQs

Prenatal Care — MCQs

On this page

Practice by Chapter

Want unlimited practice?