Prenatal Care — MCQs

Prenatal Care Indian Medical PG Practice Questions and MCQs

Question 311: Prenatal diagnosis at 18-20 weeks of gestation can be performed using all of the following methods, except:

A. Amniotic fluid
B. Maternal blood
C. Chorionic villus sampling (Correct Answer)
D. Fetal blood

Explanation: **Explanation:** The correct answer is **C. Chorionic villus sampling (CVS)**. The primary reason CVS is the correct answer is the **timing of the procedure**. CVS is a first-trimester prenatal diagnostic tool, typically performed between **10 and 13 weeks** of gestation. By 18–20 weeks, the chorion frondosum has transformed into the definitive placenta, making CVS technically inappropriate and clinically obsolete for that gestational age. **Analysis of other options:** * **A. Amniotic Fluid (Amniocentesis):** This is the "gold standard" for diagnosis in the second trimester. It is ideally performed between **15 and 20 weeks**, making it a perfectly valid method for the 18–20 week window. * **B. Maternal Blood:** Maternal serum screening (Triple or Quadruple markers) is routinely performed between **15 and 20 weeks** to assess the risk of aneuploidies and neural tube defects. Additionally, Non-Invasive Prenatal Testing (NIPT/cfDNA) can be performed anytime after 10 weeks. * **D. Fetal Blood (Cordocentesis/PUBS):** Percutaneous Umbilical Blood Sampling is generally performed **after 18 weeks** when the umbilical vein is large enough to be punctured under ultrasound guidance. **High-Yield Clinical Pearls for NEET-PG:** * **CVS Timing:** 10–13 weeks. Performing it before 10 weeks is associated with **Limb Reduction Defects**. * **Amniocentesis Timing:** 15–20 weeks. Early amniocentesis (11–14 weeks) is avoided due to higher risks of clubfoot (talipes equinovarus) and procedure failure. * **Cordocentesis:** Best for rapid karyotyping (results in 48–72 hours) or diagnosing fetal infections and anemia. * **Most common complication:** For both CVS and Amniocentesis, the most common risk is fetal loss (approx. 0.5–1%).

Question 312: A woman presents at term pregnancy for her first antenatal visit and tests positive for HIV in screening and confirmatory tests. What is the next step in management?

A. Start antiretroviral therapy (ART) after clinical staging.
B. Plan an early delivery and start ART after it.
C. Start ART immediately. (Correct Answer)
D. Start ART after CD4 count results.

Explanation: The core principle in managing HIV during pregnancy is the prevention of parent-to-child transmission (PPTCT). According to current WHO and National AIDS Control Organization (NACO) guidelines, the "Test and Treat" policy applies to all pregnant women. **Why Option C is correct:** In this scenario, the woman is already at term. The risk of vertical transmission is highest during labor and delivery. Starting Antiretroviral Therapy (ART) **immediately**—regardless of clinical stage or CD4 count—is critical to rapidly reduce the viral load before delivery. Even a few doses of ART can significantly lower the risk of transmission to the neonate. **Analysis of Incorrect Options:** * **Option A & D:** Waiting for clinical staging or CD4 count results causes unnecessary delay. Under the current guidelines, ART is initiated for all pregnant women immediately upon diagnosis to prioritize fetal protection, irrespective of their immunological or clinical status. * **Option B:** Delaying ART until after delivery misses the window of highest transmission risk. While the mode of delivery (Vaginal vs. Cesarean) may be decided based on viral load, ART must be started as soon as the diagnosis is confirmed. **Clinical Pearls for NEET-PG:** * **Preferred Regimen (NACO):** TLD (Tenofovir + Lamivudine + Dolutegravir) is the first-line ART for pregnant women. * **Zidovudine (AZT):** If the mother's viral load is unknown or >1000 copies/mL near delivery, IV Zidovudine is administered during labor. * **Infant Prophylaxis:** The neonate should receive Nevirapine (NVP) or Zidovudine (AZT) syrup for 6–12 weeks depending on the risk category. * **Breastfeeding:** Exclusive breastfeeding is recommended for the first 6 months, provided the mother is adherent to ART.

Question 313: Which of the following vaccines is NOT contraindicated in pregnancy?

A. Measles
B. Hepatitis B (Correct Answer)
C. Varicella
D. BCG

Explanation: **Explanation:** The fundamental principle in prenatal vaccination is the distinction between **Live-Attenuated Vaccines** and **Inactivated/Recombinant Vaccines**. **1. Why Hepatitis B is the Correct Answer:** Hepatitis B is a **subunit (recombinant) vaccine** containing only the HBsAg protein, not the live virus. It is non-infectious and poses no risk to the fetus. It is indicated during pregnancy for women at high risk of infection (e.g., healthcare workers, those with infected partners). Other safe vaccines in pregnancy include Tdap (routinely recommended), Influenza (inactivated), and Rabies. **2. Why the Other Options are Incorrect:** * **Measles (Option A):** This is a live-attenuated vaccine. Live vaccines carry a theoretical risk of viral replication and transmission to the fetus, potentially causing congenital anomalies or fetal infection. * **Varicella (Option B):** This is a live-attenuated vaccine. It is strictly contraindicated; women are advised to avoid pregnancy for at least one month after receiving this vaccine. * **BCG (Option D):** This is a live-attenuated bacterial vaccine (Bacillus Calmette-Guérin). While no harmful effects on the fetus have been proven, it is avoided as a precautionary measure. **NEET-PG High-Yield Pearls:** * **Rule of Thumb:** All **Live Vaccines** (MMR, Varicella, BCG, Yellow Fever, Oral Polio, Oral Typhoid) are **contraindicated**. * **Routine Recommendation:** The **Tdap** vaccine is recommended in every pregnancy (ideally between 27–36 weeks) to provide passive immunity to the neonate against Pertussis. * **Influenza:** The **inactivated** injectable flu shot is safe and recommended in any trimester during flu season. * **Postpartum:** Live vaccines (like MMR) should be administered immediately postpartum if the mother is non-immune.

Question 314: What is the most accurate method of diagnosing pregnancy at 6 weeks?

A. Hegar's sign
B. X-ray examination
C. Palpation of fetal parts
D. Fetal heart sound by USG (Correct Answer)

Explanation: **Explanation:** The diagnosis of pregnancy is categorized into presumptive, probable, and positive signs. At 6 weeks of gestation, the most accurate and definitive method is the visualization of **fetal heart activity via Transvaginal Sonography (TVS).** **1. Why Option D is Correct:** Fetal heart sound/activity is a **positive (certain) sign** of pregnancy. Using TVS, a gestational sac is visible at 4.5–5 weeks, a yolk sac at 5 weeks, and fetal cardiac activity can be detected as early as **5.5 to 6 weeks**. Detecting cardiac activity confirms not just pregnancy, but a viable intrauterine pregnancy. **2. Why Other Options are Incorrect:** * **A. Hegar’s Sign:** This is a **probable sign** of pregnancy. it refers to the softening of the uterine isthmus, typically palpable between **6–10 weeks**. While suggestive, it is subjective and not diagnostic. * **B. X-ray examination:** Fetal skeletal shadows only appear on X-ray after **16 weeks** (when mineralization occurs). Furthermore, X-rays are contraindicated in early pregnancy due to the risk of teratogenicity. * **C. Palpation of fetal parts:** This is a positive sign but can only be performed much later, typically after **20 weeks** of gestation. **High-Yield Clinical Pearls for NEET-PG:** * **Earliest sign of pregnancy on USG:** Gestational sac (at 4.5–5 weeks). * **Discriminatory Zone:** The level of serum β-hCG at which a gestational sac should be visible on USG (TVS: 1,500–2,000 mIU/mL; TAS: 6,500 mIU/mL). * **Fetal Heart Rate (FHR):** Can be heard by **Doppler** at 10–12 weeks and by **Pinard stethoscope** at 18–20 weeks. * **Most accurate method for dating:** Crown-Rump Length (CRL) measured between 7–12 weeks.

Question 315: A mother at 10 weeks gestation has a history of a previous delivery with an open neural tube defect. Which statement is true regarding her current pregnancy?

A. Sodium valproate use is associated with an increased risk of open neural tube defects. (Correct Answer)
B. The risk of recurrence of open neural tube defects is approximately 10%.
C. Amniocentesis should be performed to assess for open neural tube defects.
D. The mother should be advised to take multivitamins.

Explanation: **Explanation:** **1. Why Option A is Correct:** Sodium valproate is a potent teratogen. It interferes with folate metabolism and increases the risk of **Neural Tube Defects (NTDs)**, specifically spina bifida, by approximately 10-20 times compared to the general population. In a patient with a prior history of NTD, avoiding such teratogens is a critical component of preconception and prenatal counseling. **2. Why Other Options are Incorrect:** * **Option B:** The recurrence risk of NTD after one affected pregnancy is approximately **2-3%** (not 10%). The risk increases to about 10% only after two previously affected pregnancies. * **Option C:** While amniocentesis (measuring Alpha-fetoprotein and Acetylcholinesterase) can detect NTDs, it is an invasive procedure. The primary screening tool is a **High-resolution Level II Ultrasound (Anomaly Scan)** performed at 18–20 weeks, which has a high sensitivity for detecting open NTDs. * **Option D:** While multivitamins are beneficial, the specific recommendation for this patient is **High-dose Folic Acid (4 mg/day)**. Standard multivitamins do not contain enough folic acid to prevent recurrence in high-risk cases. **High-Yield Clinical Pearls for NEET-PG:** * **Folic Acid Dosage:** * *Low risk:* 400 mcg (0.4 mg) daily (started 1 month pre-conception). * *High risk (prior NTD, DM, or Anti-epileptics):* **4 mg daily** (started 3 months pre-conception). * **Timing:** The neural tube closes by **day 28** of gestation; therefore, supplementation must begin pre-conceptionally to be effective. * **Screening:** Maternal Serum Alpha-Fetoprotein (MSAFP) is elevated in open NTDs but is decreased in Down Syndrome.

Question 316: An ultrasound measures a parameter at 3.7 mm. What does this measurement indicate?

A. A normal finding
B. A finding higher than normal (Correct Answer)
C. A finding lesser than normal
D. The scan should be repeated at 18 weeks

Explanation: ***A finding higher than normal*** - A **nuchal translucency (NT)** measurement of 3.7 mm exceeds the normal threshold of **<3.0-3.5 mm** at 11-13+6 weeks gestation. - This increased NT is associated with **higher risk of chromosomal abnormalities** like **Down syndrome (Trisomy 21)** and **congenital heart defects**. *A normal finding* - Normal **nuchal translucency** should be **less than 3.0-3.5 mm** depending on gestational age and laboratory standards. - A measurement of 3.7 mm clearly exceeds the established **upper limit of normal** for NT screening. *A finding lesser than normal* - **Nuchal translucency** measurements are concerning when they are **increased**, not decreased. - Lower NT values are generally **reassuring** and associated with lower risk of chromosomal abnormalities. *The scan should be repeated at 18 weeks* - **Nuchal translucency** is specifically measured between **11-13+6 weeks** gestation when it is most accurate. - At 18 weeks, NT measurement is **no longer valid** as the nuchal fold naturally resolves by this time.

Question 317: All are positive signs of pregnancy except:

A. Vomiting
B. Fetal movements
C. Fetal heart sounds
D. Excessive salivation (Correct Answer)

Explanation: ### Explanation In Obstetrics, signs of pregnancy are categorized into three groups: **Presumptive, Probable, and Positive.** **1. Why "Excessive Salivation" is the correct answer:** The question asks for the exception among "positive signs." **Excessive salivation (Ptyalism)** and **Vomiting** are both **Presumptive signs**. These are subjective symptoms experienced by the patient or objective signs that are not diagnostic of pregnancy because they can be caused by other medical conditions. Since the question likely contains a technical error in its construction (as both A and D are presumptive), **Excessive Salivation** is the most appropriate "exception" because it is a minor, non-specific symptom, whereas positive signs must be definitive proof of a live fetus. **2. Analysis of other options:** * **Fetal Heart Sounds (C):** This is a **Positive sign**. Detection of the fetal heartbeat via Doppler (at 10–12 weeks) or Fetoscope (at 18–20 weeks) is absolute proof of pregnancy. * **Fetal Movements (B):** When felt by an **examiner** (not just the mother), active fetal movements are a **Positive sign**. (Note: "Quickening" felt by the mother is only presumptive). * **Vomiting (A):** This is a **Presumptive sign**. While common in the first trimester due to hCG, it can be caused by gastrointestinal issues. **3. NEET-PG High-Yield Pearls:** * **Positive Signs (Diagnostic):** 1. Visualization of fetus by Ultrasound (Gestational sac at 5 weeks); 2. Fetal heart activity; 3. Fetal movements felt by examiner; 4. Identification of fetal skeleton on X-ray (rarely used now). * **Probable Signs (Objective):** Hegar’s sign, Goodell’s sign, Chadwick’s sign, Braxton Hicks contractions, and positive urine/serum pregnancy tests (hCG can be elevated in molar pregnancy or choriocarcinoma). * **Presumptive Signs (Subjective):** Amenorrhea, nausea/vomiting, breast tenderness, urinary frequency, and fatigue.

Question 318: What does Goodell's sign indicate?

A. Pulsation in the lateral vaginal fornix
B. Bluish discoloration of the vagina
C. Softening of the cervix from the lower part upwards (Correct Answer)
D. On bimanual palpation, the fingers can be approximated, as if nothing is in between

Explanation: **Explanation:** **Goodell’s Sign** is a clinical indicator of pregnancy characterized by the **softening of the cervix**. Under the influence of increased estrogen and progesterone, there is marked vascularity, congestion, and edema of the cervical tissues. This causes the cervix, which normally feels like the "tip of the nose" in a non-pregnant state, to feel as soft as the "lips of the mouth" or "earlobe" starting from the 6th week of gestation. The softening typically progresses from the lower part upwards. **Analysis of Options:** * **Option A (Pulsation in the lateral vaginal fornix):** This describes **Osiander’s sign**, caused by increased vascularity and pulsation of the uterine arteries felt through the lateral fornices around the 8th week. * **Option B (Bluish discoloration of the vagina):** This describes **Chadwick’s sign** (or Jacquemier’s sign), resulting from pelvic congestion and venous stasis, typically visible by the 6th–8th week. * **Option D (Approximation of fingers on bimanual palpation):** This describes **Hegar’s sign**. Due to the softening of the isthmus (the lower uterine segment), the upper body of the uterus and the cervix feel like two separate entities, allowing the fingers to nearly meet during a bimanual exam. **High-Yield Clinical Pearls for NEET-PG:** 1. **Timeline:** Most presumptive/probable signs of pregnancy (Goodell’s, Chadwick’s, Hegar’s) appear between **6–10 weeks**. 2. **Palmer’s Sign:** Regular, rhythmic uterine contractions felt during a bimanual examination as early as 4–8 weeks. 3. **Ladin’s Sign:** Softening of the anterior midline of the uterus at the cervico-uterine junction (6th week). 4. **Piskacek’s Sign:** Asymmetrical enlargement of the uterus if implantation occurs near one of the cornua.

Question 319: Which of the following is considered a presumptive sign of pregnancy?

A. Amenorrhea (Correct Answer)
B. Fetal cardiac activity
C. Ballottement
D. Hegar sign

Explanation: In Obstetrics, signs of pregnancy are categorized into three groups based on their diagnostic reliability: **Presumptive, Probable, and Positive.** ### 1. Why Amenorrhea is the Correct Answer **Amenorrhea** is a **Presumptive sign**. These are subjective symptoms or objective signs noticed by the patient that suggest pregnancy but are not diagnostic because they can be caused by other conditions (e.g., stress, endocrine disorders, or strenuous exercise). Other presumptive signs include nausea/vomiting (morning sickness), breast tenderness, urinary frequency, and fatigue. ### 2. Why the Other Options are Incorrect * **B. Fetal cardiac activity:** This is a **Positive sign**. Positive signs are objective findings that confirm the presence of a fetus beyond doubt. These include ultrasound visualization, detection of fetal heart tones, and palpation of fetal movements by an examiner. * **C. Ballottement:** This is a **Probable sign**. Probable signs are objective findings observed by the clinician that strongly suggest pregnancy but are not 100% definitive. Ballottement (the rebound of the fetus against the finger) can occasionally be mimicked by uterine tumors or cysts. * **D. Hegar sign:** This is also a **Probable sign**. It refers to the softening of the lower uterine segment (isthmus) noted during bimanual examination between 6–10 weeks of gestation. ### 3. High-Yield Clinical Pearls for NEET-PG * **Chadwick’s Sign:** Bluish discoloration of the cervix/vagina (Probable sign). * **Goodell’s Sign:** Softening of the cervix (Probable sign). * **Quickening:** The first perception of fetal movement by the mother (Presumptive sign, as it is subjective). * **hCG in Urine/Blood:** Classified as a **Probable sign** because certain tumors (e.g., Choriocarcinoma) can also secrete hCG.

Question 320: Which diagnostic method is best for detecting neural tube defects?

A. Ultrasound (USG)
B. Chromosomal analysis
C. Amniocentesis (Correct Answer)
D. Placentography

Explanation: **Explanation:** The detection of Neural Tube Defects (NTDs) relies on identifying elevated levels of **Alpha-fetoprotein (AFP)** and the presence of **Acetylcholinesterase (AChE)**. **Why Amniocentesis is the Correct Answer:** While maternal serum AFP (MSAFP) is a common screening tool, **amniocentesis** is considered the gold standard diagnostic method. It allows for the measurement of **Amniotic Fluid AFP (AFAFP)**. If AFAFP is elevated, the sample is tested for **Acetylcholinesterase (AChE)**. AChE is highly specific; its presence in amniotic fluid confirms an open NTD (like anencephaly or spina bifida) because this enzyme leaks directly from exposed neural tissue into the amniotic sac. **Analysis of Incorrect Options:** * **A. Ultrasound (USG):** While high-resolution (Level II) ultrasound is excellent for visualizing structural defects (e.g., "lemon sign" or "banana sign"), it is operator-dependent. Amniocentesis provides definitive biochemical confirmation. * **B. Chromosomal analysis:** NTDs are primarily structural/multifactorial defects, not typically caused by numerical or structural chromosomal aberrations (like Trisomy 21). * **D. Placentography:** This is an obsolete technique formerly used to visualize the placenta; it has no role in diagnosing fetal structural anomalies. **NEET-PG High-Yield Pearls:** * **Best Screening Test:** Maternal Serum AFP (done at 15–20 weeks). * **Most Specific Diagnostic Marker:** Acetylcholinesterase (AChE) in amniotic fluid. * **Prevention:** 400 mcg/day of Folic Acid (pre-conceptionally) reduces NTD risk by 70%. For women with a previous history of NTD, the dose is increased to **4 mg/day**. * **Anencephaly:** The most common NTD; associated with polyhydramnios due to failure of the fetal swallowing reflex.

Practice by Chapter

Preconception Counseling

Practice Questions

Pregnancy Diagnosis and Dating

Practice Questions

Routine Antenatal Assessments

Practice Questions

Maternal Physiological Changes

Practice Questions

Nutrition in Pregnancy

Practice Questions

Screening Tests in Pregnancy

Practice Questions

Fetal Growth Assessment

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High-Risk Pregnancy Identification

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Antenatal Complications Management

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Psychosocial Aspects of Pregnancy

Practice Questions

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