Maternal-Fetal Medicine Practice Questions

Q: Which maternal condition is associated with fetal Long-Chain Hydroxyacyl-CoA Dehydrogenase (LCHAD) deficiency?

HELLP syndrome. **Explanation:** The association between fetal **Long-Chain Hydroxyacyl-CoA Dehydrogenase (LCHAD) deficiency** and maternal liver diseases like **HELLP syndrome** and **Acute Fatty Liver of Pregnancy (AFLP)** is a high-yield concept in obstetric medicine. **Why HELLP syndrome is correct:** LCHAD is a mitochondrial enzyme involved in the beta-oxidation of fatty acids. When a fetus has an autosomal recessive LCHAD deficiency, it cannot metabolize long-chain fatty acids. These intermediate fatty acid metabolites (3-hydroxyacyl compounds) accumulate in the fetal circulation and cross the placenta into the maternal circulation. Because the mother is a carrier (heterozygous) for the mutation, her liver has reduced capacity to process these extra metabolites. This leads to lipotoxicity, causing maternal hepatocyte damage, which manifests clinically as **HELLP syndrome** (Hemolysis, Elevated Liver enzymes, Low Platelets) or **AFLP**. **Why the other options are incorrect:** * **PCOS:** This is an endocrine disorder characterized by hyperandrogenism and insulin resistance; it has no metabolic link to fetal fatty acid oxidation. * **Molar pregnancy:** This is a gestational trophoblastic disease resulting from abnormal fertilization; it is not associated with fetal metabolic enzyme deficiencies. * **Ectopic pregnancy:** This refers to implantation outside the uterine cavity and is unrelated to fetal metabolic pathways. **Clinical Pearls for NEET-PG:** * **AFLP and LCHAD:** Approximately 15–20% of mothers carrying an LCHAD-deficient fetus will develop AFLP or HELLP. * **Management:** If a mother develops AFLP/HELLP, the newborn should be screened for LCHAD deficiency immediately after birth to prevent fatal hypoglycemia and liver failure. * **Inheritance:** LCHAD deficiency follows an **Autosomal Recessive** pattern.

Q: What is the total iron requirement during pregnancy?

1000 mg. **Explanation:** The total iron requirement during a normal singleton pregnancy is approximately **1000 mg**. This requirement is driven by the physiological demands of both the mother and the developing fetus. The distribution of this 1000 mg is as follows: * **Fetus and Placenta:** ~300 mg * **Expansion of Maternal Red Cell Mass:** ~450 mg (to support increased oxygen delivery) * **Obligatory Losses (Skin, Gut, Urine):** ~200 mg * **Blood Loss during Delivery:** ~50 mg (net loss) **Analysis of Options:** * **Option A (1000 mg):** Correct. This represents the cumulative need across all three trimesters. * **Option B (35 mg):** Incorrect. This is roughly the daily iron requirement during the third trimester (approx. 6–7 mg/day), not the total pregnancy requirement. * **Option C (500 mg):** Incorrect. This only covers the maternal red cell expansion but ignores fetal needs and obligatory losses. * **Option D (800 mg):** Incorrect. While some older texts cited 800 mg, modern obstetric guidelines (Williams Obstetrics) standardize the total requirement at 1000 mg. **Clinical Pearls for NEET-PG:** * **Iron Absorption:** Iron absorption increases significantly as pregnancy progresses (minimal in the 1st trimester, peaking in the 3rd). * **Prophylactic Dose:** The Government of India (IFA program) recommends **60 mg elemental iron + 500 mcg folic acid** daily for 180 days starting from the second trimester. * **Therapeutic Dose:** For diagnosed anemia (Hb <11 g/dL), the dose is doubled (120 mg elemental iron daily). * **Net Gain:** Despite the 1000 mg requirement, the "net loss" to the mother is only about 500–600 mg because the iron used for red cell expansion is returned to maternal stores after delivery.

Q: Amnion nodosum is characterized by which of the following?

Multiple, small, tan amnionic lesions. **Explanation:** **Amnion nodosum** is a specific pathological condition of the placenta characterized by the presence of multiple, small (1–3 mm), firm, gray-to-yellow/tan nodules on the fetal surface of the amnion. These nodules are composed of deposits of vernix caseosa, desquamated fetal squames, and lanugo hair that have become embedded in the amnionic epithelium. **Why the correct answer is right:** The hallmark of amnion nodosum is the presence of **multiple, small, tan amnionic lesions**. These lesions form due to severe and prolonged **oligohydramnios** (most commonly associated with renal agenesis/Potter sequence or prolonged rupture of membranes). In the absence of sufficient amniotic fluid, the fetal skin rubs directly against the amnion, causing fetal debris to scrape off and aggregate into these characteristic nodules. **Why other options are incorrect:** * **Option A & B:** Amnion nodosum does not involve generalized thickening or redundant folds. While the amnion may appear dull, the pathology is focal and nodular, not a diffuse structural change of the membrane itself. * **Option D:** Fenestrations (holes) in the amniochorion are characteristic of **Amniotic Band Syndrome**, where the rupture of the amnion leads to fibrous bands that can entangle or amputate fetal limbs. **High-Yield Facts for NEET-PG:** * **Clinical Association:** Always associate Amnion nodosum with **severe oligohydramnios**. * **Differential Diagnosis:** Do not confuse it with **Squamous Metaplasia** of the amnion. Squamous metaplasia consists of white, opaque plaques (usually near the umbilical cord insertion) that *cannot* be easily scraped off, whereas amnion nodosum nodules are easily removed. * **Potter Sequence:** If a question mentions amnion nodosum and pulmonary hypoplasia, the underlying cause is likely bilateral renal agenesis.

Q: What is the normal pH of amniotic fluid?

7.2. **Explanation:** The correct answer is **C. 7.2**. Amniotic fluid is a dynamic medium that surrounds the fetus. In a normal pregnancy, the pH of amniotic fluid is typically **slightly alkaline**, ranging between **7.0 and 7.5** (average 7.2). This alkalinity is primarily due to the composition of the fluid, which includes fetal urine (which becomes more significant as the pregnancy progresses) and secretions from the fetal respiratory tract and amnion. **Analysis of Options:** * **A & B (6.2 and 6.8):** These values are **acidic**. The normal vaginal pH is acidic (usually 3.8 to 4.5) due to the presence of *Lactobacillus*. Finding a pH in this range would be normal for the vagina but abnormal for amniotic fluid. * **D (8.2):** This value is **highly alkaline**. While amniotic fluid is basic, a pH of 8.2 is outside the physiological norm for a healthy pregnancy. **Clinical Pearls for NEET-PG:** 1. **Nitrazine Test:** This is a high-yield clinical application. Since amniotic fluid is alkaline (pH >7.0) and vaginal secretions are acidic (pH 6.0, suggesting the presence of amniotic fluid. 2. **False Positives:** The Nitrazine test can give false positives if contaminated with blood, semen, or antiseptic solutions (like povidone-iodine), as these are also alkaline. 3. **Composition:** Early in pregnancy, amniotic fluid is an ultrafiltrate of maternal plasma. By the second half, fetal urine becomes the major contributor.

Q: Which of the following is NOT true about cervical incompetence?

Associated with first-trimester abortion. **Explanation:** Cervical incompetence (now often termed cervical insufficiency) refers to the inability of the cervix to retain a pregnancy in the absence of signs and symptoms of clinical contractions, labor, or both. **Why Option A is the correct answer:** Cervical incompetence is characteristically associated with **painless, mid-trimester (second-trimester) pregnancy loss**, typically occurring between 16 and 24 weeks of gestation. First-trimester abortions (before 12 weeks) are most commonly due to chromosomal abnormalities or endocrine factors, not structural cervical weakness. **Analysis of other options:** * **Option B:** In a non-pregnant state, the diagnosis can be suggested if a **No. 8 Hegar dilator** passes through the internal os without resistance or pain. Other diagnostic tests include the "balloon test" or hysterosalpingography showing a "funneling" of the cervix. * **Option C:** Cervical incompetence can be **acquired** due to surgical trauma (e.g., D&C, conization, or cervical lacerations during previous deliveries) or can be congenital (e.g., DES exposure or collagen disorders like Ehlers-Danlos syndrome). * **Option D:** As mentioned, the hallmark of this condition is recurrent second-trimester losses preceded by spontaneous rupture of membranes or painless cervical dilation. **High-Yield NEET-PG Pearls:** * **Gold Standard Treatment:** Cervical Cerclage (McDonald or Shirodkar technique). * **Timing of Cerclage:** Usually performed between **12–14 weeks** of gestation. * **Removal:** The stitch is typically removed at **37 weeks** or at the onset of labor. * **Ultrasound Finding:** "Funneling" of the internal os and a cervical length of **<25 mm** before 24 weeks are significant markers.

Q: A gravida 3 female with a history of 2 previous second-trimester abortions presents at 22 weeks of gestation with cervical funneling. What is the most appropriate management?

Apply McDonald suture. **Explanation:** The clinical presentation of a patient with a history of recurrent second-trimester losses and current ultrasound findings of **cervical funneling** is diagnostic of **Cervical Insufficiency** (Incompetence). 1. **Why Option D is Correct:** The management of choice for cervical insufficiency is **Cervical Cerclage**. The **McDonald suture** is the most commonly performed technique. It involves a purse-string suture placed at the cervicovaginal junction to provide mechanical support to the internal os, preventing premature dilation. In this case, since the patient is already at 22 weeks with funneling, this is considered an **"Ultrasound-indicated" or "Urgent" cerclage**, typically performed between 14–24 weeks when cervical changes are detected. 2. **Why Other Options are Incorrect:** * **Options A & B (Dinoprostone/Misoprostol):** These are prostaglandins used for cervical ripening and induction of labor or abortion. Administering them would worsen the condition by further softening the cervix and inducing contractions. * **Option C (Fothergill Suture):** This is a component of the Fothergill (Manchester) operation used for treating **pelvic organ prolapse**, not cervical incompetence. It involves shortening the cardinal ligaments and is contraindicated during pregnancy. **Clinical Pearls for NEET-PG:** * **Gold Standard Diagnosis:** Transvaginal Ultrasound (TVS) showing a cervical length **<25 mm** or significant **funneling** (beaking of internal os). * **Timing:** Prophylactic (History-based) cerclage is usually done at **12–14 weeks**. * **Shirodkar Technique:** An alternative to McDonald’s where the suture is placed submucosally; it is technically more difficult but may be used if the McDonald suture fails. * **Contraindications to Cerclage:** Chorioamnionitis, ruptured membranes, active bleeding, or fetal anomalies.

Q: A 26-year-old pregnant woman has a diastolic murmur in the mitral area. Echocardiography reveals the mitral valve orifice to be 0.8 cm 2. What is the cause of her murmur?

Severe mitral stenosis. **Explanation:** The patient presents with a diastolic murmur in the mitral area and an echocardiographic finding of a mitral valve orifice area of **0.8 cm²**. This is a classic presentation of **Mitral Stenosis (MS)**, the most common valvular lesion encountered in pregnancy, usually secondary to Rheumatic Heart Disease. **Why Option B is Correct:** According to the severity grading of Mitral Stenosis: * **Normal mitral valve area:** 4.0 – 6.0 cm² * **Mild MS:** > 1.5 cm² * **Moderate MS:** 1.0 – 1.5 cm² * **Severe MS:** 1.5 cm². * **Option C:** Functional (physiologic) murmurs in pregnancy are almost always **systolic** due to increased blood flow (hyperdynamic circulation). A diastolic murmur is **always pathological** and requires investigation. * **Option D:** Murmurs from fetal heart defects are not audible through the maternal chest wall via a stethoscope. **NEET-PG High-Yield Pearls:** 1. **Most common heart disease in pregnancy:** Rheumatic Heart Disease (Mitral Stenosis is the most common lesion). 2. **Most common cause of maternal death in heart disease:** Heart failure (often during the 28–32 week window or the immediate postpartum period). 3. **Management:** Beta-blockers (e.g., Propranolol/Metoprolol) are used to control heart rate. If intervention is needed, **Balloon Mitral Valvotomy (BMV)** is the procedure of choice, preferably after the first trimester. 4. **Labor:** Vaginal delivery with shortened second stage (using forceps/ventouse) is preferred over C-section.

Q: What predicted beta-hCG levels are indicative of an ectopic pregnancy?

1500 mIU/mL. The correct answer is **1500 mIU/mL**. ### **Explanation of the Correct Answer** The core concept here is the **Discriminatory Zone (DZ)**. This is the threshold level of serum beta-hCG above which a normal intrauterine pregnancy (IUP) should consistently be visible via transvaginal sonography (TVS). * According to the **ACOG guidelines** and standard textbooks (Williams Obstetrics), the most widely accepted discriminatory zone is **1500 to 2000 mIU/mL**. * If the beta-hCG is above 1500 mIU/mL and the uterus is empty on TVS, the clinician must highly suspect an **ectopic pregnancy** or a non-viable IUP. ### **Analysis of Incorrect Options** * **A (1000 mIU/mL):** This was the historical threshold for older ultrasound machines. Modern high-resolution TVS can often see a sac at this level, but it is not the standard "discriminatory" cutoff used to diagnose ectopic pregnancy. * **C & D (2000 & 2500 mIU/mL):** While some institutions use 2000 mIU/mL to increase specificity (to avoid accidental termination of a desired pregnancy), **1500 mIU/mL** remains the classic, most frequently tested "lower limit" of the discriminatory zone for NEET-PG. 2500 mIU/mL is generally considered too high for a primary diagnostic threshold. ### **Clinical Pearls for NEET-PG** 1. **Doubling Time:** In a healthy IUP, beta-hCG levels should increase by at least **35-53% every 48 hours**. A rise of less than this suggests ectopic pregnancy or miscarriage. 2. **Transabdominal Ultrasound (TAS):** The discriminatory zone for TAS is much higher, typically **6000–6500 mIU/mL**. 3. **Gold Standard Diagnosis:** While beta-hCG and TVS are the primary tools, the definitive diagnosis of ectopic pregnancy is via **laparoscopy**. 4. **Medical Management:** Methotrexate is indicated if the patient is stable, the sac is <4 cm, and beta-hCG is <5000 mIU/mL.

Question 1

Which maternal condition is associated with fetal Long-Chain Hydroxyacyl-CoA Dehydrogenase (LCHAD) deficiency?

Accepted Answer

HELLP syndrome

Answer

Polycystic Ovarian Syndrome (PCOS)

Answer

Molar pregnancy

Answer

Ectopic pregnancy

Question 2

In valvular heart disease complicating pregnancy, which of the following statements is NOT true?

Accepted Answer

Open heart surgery is associated with a reduction in fetal loss.

Answer

A closed mitral valvotomy can be carried out if symptoms of mitral stenosis are severe.

Answer

Mitral regurgitation is usually well tolerated.

Answer

A maternal mortality of 15% has been reported in women with critical aortic stenosis.

Question 3

What is the total iron requirement during pregnancy?

Accepted Answer

1000 mg

Answer

35 mg

Answer

500 mg

Answer

800 mg

Question 4

Which of the following conditions poses the greatest risk for development of pre-eclampsia?

Accepted Answer

Polyarteritis nodosa

Answer

Chronic glomerulonephritis

Answer

Polycystic kidney disease

Answer

Renal artery stenosis

Question 5

Amnion nodosum is characterized by which of the following?

Accepted Answer

Multiple, small, tan amnionic lesions

Answer

Generalized amnion thickening

Answer

Multiple, redundant folds of amnion

Answer

Multiple, small fenestrations in the amniochorion

Question 6

What is the normal pH of amniotic fluid?

Accepted Answer

7.2

Answer

6.2

Answer

6.8

Answer

8.2

Question 7

Which of the following is NOT true about cervical incompetence?

Accepted Answer

Associated with first-trimester abortion

Answer

Hegar's dilator can be passed into the uterine cavity in a non-pregnant state

Answer

History of trauma can precede its development

Answer

Associated with second-trimester abortion

Question 8

A gravida 3 female with a history of 2 previous second-trimester abortions presents at 22 weeks of gestation with cervical funneling. What is the most appropriate management?

Accepted Answer

Apply McDonald suture

Answer

Administer dinoprostone and bed rest

Answer

Administer misoprostol and bed rest

Answer

Apply Fothergill suture

Question 9

A 26-year-old pregnant woman has a diastolic murmur in the mitral area. Echocardiography reveals the mitral valve orifice to be 0.8 cm
2. What is the cause of her murmur?

Accepted Answer

Severe mitral stenosis

Answer

Mild mitral stenosis

Answer

Functional murmur

Answer

Transmitted murmur from congenital heart disease of the fetus

Question 10

What predicted beta-hCG levels are indicative of an ectopic pregnancy?

Accepted Answer

1500 mIU/mL

Answer

1000 mIU/mL

Answer

2000 mIU/mL

Answer

2500 mIU/mL

Maternal-Fetal Medicine — MCQs

Maternal-Fetal Medicine — MCQs

On this page

Practice by Chapter

Want unlimited practice?