Maternal-Fetal Medicine — MCQs

Maternal-Fetal Medicine Indian Medical PG Practice Questions and MCQs

Question 1171: With reference to fetal heart rate, a nonstress test is considered reactive when?

A. Two fetal heart rate accelerations are noted in 20 minutes (Correct Answer)
B. One fetal heart rate acceleration is noted in 20 minutes
C. Two fetal heart rate accelerations are noted in 10 minutes
D. Three fetal heart rate accelerations are noted in 30 minutes

Explanation: **Two fetal heart rate accelerations are noted in 20 minutes** - A **nonstress test (NST)** is considered reactive when there are at least two accelerations of the fetal heart rate within a 20-minute period. - An **acceleration** is defined as an increase in fetal heart rate of at least 15 beats per minute above baseline, lasting for at least 15 seconds (for gestations ≥32 weeks). - This is the **standard definition** of a reactive NST and indicates adequate fetal well-being. *One fetal heart rate acceleration is noted in 20 minutes* - While an acceleration is a positive sign, a **reactive NST** specifically requires at least two accelerations within the 20-minute timeframe. - A single acceleration within 20 minutes would render the NST **non-reactive**, requiring further evaluation or extended monitoring up to 40 minutes. *Two fetal heart rate accelerations are noted in 10 minutes* - While two accelerations occurring in 10 minutes is clinically reassuring and technically occurs within 20 minutes, the **standard definition** for reporting NST reactivity specifically states "two or more accelerations **in** 20 minutes." - The 20-minute observation period is the established timeframe for NST assessment, not 10 minutes. - This option tests knowledge of the precise standard criteria rather than clinical interpretation. *Three fetal heart rate accelerations are noted in 30 minutes* - The standard definition for a **reactive NST** requires assessment within a **20-minute window**, not 30 minutes. - While three accelerations indicate fetal well-being, this exceeds the standard observation period and does not meet the formal definition of a reactive NST within the specified timeframe. - An NST is typically extended to 40 minutes if non-reactive at 20 minutes, but the definition of reactivity remains based on the 20-minute criterion.

Question 1172: In the context of fetal hypoxia, which parameter of the Biophysical Profile (BPP) is typically affected last?

A. Fetal tone (Correct Answer)
B. Fetal breathing movements
C. Fetal movements
D. Non-stress test (NST)

Explanation: ***Fetal tone*** - **Fetal tone** is the last biophysical parameter to be affected by worsening fetal hypoxia as it is controlled by the **lower brainstem and spinal cord**, which are the most primitive centers and spared until late decompensation. - This parameter requires significant and prolonged oxygen deprivation to be compromised, indicating severe fetal compromise. *Fetal breathing movements* - **Fetal breathing movements** are affected relatively early in fetal hypoxia, as they are controlled by the **upper brainstem (pons)** and thus more sensitive to oxygen deprivation. - Absence or decreased frequency of these movements can be an early sign of impending hypoxia. *Fetal movements* - **Gross fetal body movements** are also affected early by oxygen deprivation, as they are controlled by the fetal **cerebral cortex** and subcortical centers. - A reduction in fetal movements often signifies the fetus is conserving energy due to oxygen scarcity. *Non-stress test (NST)* - The **non-stress test (NST)**, which assesses **fetal heart rate accelerations** in response to movement, is typically the *first* parameter to be affected by hypoxia. - Loss of fetal heart rate accelerations occurs early because the **autonomic nervous system and cortical centers**, which control these responses, are highly sensitive to reduced oxygen levels.

Question 1173: Which of the following statements about cardiovascular changes during pregnancy is true?

A. Increase in left ventricular end diastolic diameter (Correct Answer)
B. None of the options are true
C. Cardiac output decreases during pregnancy
D. Pregnancy causes right axis deviation

Explanation: ***Increase in left ventricular end diastolic diameter*** - Pregnancy leads to a significant increase in **blood volume** (up to 50% by the third trimester), which directly increases **venous return** to the heart. - This increased preload stretches the left ventricle, causing an increase in its **end-diastolic dimension** and volume to accommodate the larger blood volume. *Cardiac output decreases during pregnancy* - **Cardiac output actually increases** significantly during pregnancy, by 30-50%, reaching its peak in the second trimester and remaining high until delivery. - This increase is necessary to meet the metabolic demands of the growing fetus and uteroplacental unit, and is primarily driven by an increase in **stroke volume** and **heart rate**. *Pregnancy causes right axis deviation* - Pregnancy typically causes a **leftward shift of the cardiac axis**, leading to **left axis deviation** (or a more horizontal axis) on an electrocardiogram. - This is due to the elevation of the diaphragm by the gravid uterus, which pushes the heart superiorly and to the left. *None of the options are true* - This statement is incorrect because the increase in **left ventricular end-diastolic diameter** during pregnancy is a well-established physiological change. - The other two options are false, but there is a correct statement among the choices.

Question 1174: What is the most common heart disease in pregnancy?

A. Aortic Stenosis (AS)
B. Mitral Regurgitation (MR)
C. Mitral Stenosis (MS) (Correct Answer)
D. Wolff-Parkinson-White (WPW) syndrome

Explanation: **Mitral Stenosis (MS)** - **Mitral stenosis** is the most common form of **rheumatic heart disease**, which is the leading cause of heart disease in pregnant women. - Pregnancy exacerbates MS symptoms due to **increased blood volume** and **cardiac output**, leading to increased left atrial pressure and pulmonary congestion. *Aortic Stenosis (AS)* - While **aortic stenosis** can occur during pregnancy, it is less common than mitral stenosis as a primary cause of symptomatic heart disease. - The fixed outflow obstruction in AS can lead to complications, but its prevalence is lower compared to rheumatic MS. *Mitral Regurgitation (MR)* - **Mitral regurgitation** is generally better tolerated in pregnancy than stenotic lesions due to reduced afterload during gestation. - Although it can cause symptoms, it is not the most common heart disease encountered. *Wolff-Parkinson-White (WPW) syndrome* - **WPW syndrome** is an electrical conduction disorder, not a structural heart disease. - While it can manifest with arrhythmias exacerbated by pregnancy, it is not considered the most common structural heart disease in this population.

Question 1175: Which of the following conditions is NOT contraindicated in pregnancy?

A. Marfan's with aortic root dilation
B. Primary Pulmonary Hypertension
C. Eisenmenger's syndrome
D. WPW syndrome (Correct Answer)

Explanation: **WPW syndrome** - **Wolff-Parkinson-White (WPW) syndrome** is a condition involving an extra electrical pathway in the heart, leading to episodes of rapid heart rate. - While it can cause arrhythmias, severe complications in pregnancy are rare, and it is generally *not* considered an absolute contraindication for pregnancy. *Primary Pulmonary Hypertension* - **Primary Pulmonary Hypertension (PPH)** carries a very high maternal mortality rate (25-50%) due to the physiological changes of pregnancy on the cardiovascular system. - The increased blood volume and cardiac output in pregnancy can lead to severe decompensation and right heart failure in women with PPH. *Eisenmenger's syndrome* - **Eisenmenger's syndrome** is a severe form of pulmonary hypertension with a right-to-left shunt, associated with an extremely high maternal mortality rate (30-50%). - Pregnancy significantly increases the risk of **pulmonary hypertensive crisis**, right heart failure, and thromboembolic events, making it highly contraindicated. *Marfan's with aortic root dilation* - **Marfan's syndrome** with **aortic root dilation** is a significant contraindication due to the high risk of **aortic dissection** and rupture. - The hemodynamic stress of pregnancy, including increased blood volume and cardiac output, places immense strain on the dilated aorta, increasing the risk of life-threatening events.

Question 1176: At what day after fertilization is the utero-placental circulation typically established?

A. 5
B. 20
C. 10
D. 15 (Correct Answer)

Explanation: ***Day 15 (Correct Answer)*** - **Utero-placental circulation** is established around day 15 after fertilization, coinciding with the development of the **chorionic villi** and their vascularization. - At this stage, the **trophoblast** has invaded the maternal decidua, allowing for the formation of lacunae filled with maternal blood, facilitating early nutrient and waste exchange. - The **primary chorionic villi become vascularized**, creating the functional connection between maternal and fetal circulations. *Day 5 (Incorrect)* - By day 5, the embryo is typically at the **blastocyst stage** and is undergoing **hatching** from the zona pellucida before implantation. - There is no significant utero-placental circulation established at this very early stage; the embryo relies on diffusion for nourishment. *Day 10 (Incorrect)* - Around day 10, the **blastocyst is actively implanting** into the uterine wall, and the trophoblast differentiates into **cytotrophoblast** and **syncytiotrophoblast**. - While lacunae are forming within the syncytiotrophoblast and beginning to fill with maternal blood, a fully established circulatory system with functional villi is not yet present. *Day 20 (Incorrect)* - By day 20, the **utero-placental circulation** is already well-established and functional, having begun several days prior. - This later stage marks a more mature state of placental development, where the villi are more complex and efficient for exchange.

Question 1177: Up to what gestational age is the corpus luteum essential for pregnancy maintenance, such that its surgical excision would result in miscarriage?

A. Before 6 weeks
B. 8-10 weeks (Correct Answer)
C. 6-8 weeks
D. 10-12 weeks

Explanation: ***8-10 weeks*** - The corpus luteum produces **progesterone** that is essential for maintaining early pregnancy until the **luteal-placental shift** occurs. - This shift, where the **placenta takes over progesterone production**, typically completes between **7-9 weeks** of gestation. - However, to ensure safety and account for individual variation, the corpus luteum should be considered essential **up to 10 weeks**. - Surgical excision of the corpus luteum **before 10 weeks** carries significant risk of miscarriage, while removal **after 10 weeks** is generally safe as the placenta has established autonomous progesterone production. *Before 6 weeks* - While removal before 6 weeks would certainly cause miscarriage, this is not the **maximum gestational age** at which the corpus luteum remains essential. - The critical dependency extends well beyond 6 weeks. *6-8 weeks* - During this period, the corpus luteum is still **absolutely essential** for progesterone production. - The luteal-placental shift is typically **incomplete** during this timeframe. - Removal would result in miscarriage, but this is still not the maximum safe window. *10-12 weeks* - By 10-12 weeks, the **placenta has fully taken over** progesterone production. - At this stage, the corpus luteum is no longer functionally necessary, and its removal does **not increase miscarriage risk**.

Question 1178: Which of the following procedures is associated with the least risk of feto-maternal hemorrhage?

A. Amniocentesis (Correct Answer)
B. Chorionic villus sampling
C. External cephalic version
D. Cordocentesis

Explanation: ***Amniocentesis*** - This procedure involves sampling **amniotic fluid**, which is primarily fetal urine and cells, not directly blood. - The needle typically avoids the placenta and fetal vessels, making **feto-maternal hemorrhage less likely** compared to procedures directly accessing fetal blood or placental tissue. - Risk of FMH is approximately **1-2%**, the lowest among invasive prenatal procedures. *Cordocentesis* - This procedure involves direct **percutaneous umbilical blood sampling** from the umbilical cord. - Due to direct needle puncture of fetal blood vessels, the potential for **feto-maternal hemorrhage is 40-50%**. - Highest risk among diagnostic procedures listed. *Chorionic villus sampling* - This procedure involves taking a sample of the **placenta** (chorionic villi), which contains fetal cells and is rich in blood vessels. - Disrupting the placental-uterine interface can lead to **feto-maternal hemorrhage in 10-15%** of cases. - Higher risk than amniocentesis due to placental manipulation. *External cephalic version* - This procedure involves **manual manipulation** of the fetus through the maternal abdomen to convert breech to cephalic presentation. - The mechanical pressure and manipulation can cause **placental separation or disruption**, leading to FMH in approximately **2-6%** of cases. - Risk is higher than amniocentesis due to physical manipulation of the gravid uterus.

Question 1179: Which of the following is a complication of pre-eclampsia?

A. Eclampsia (Correct Answer)
B. HELLP syndrome
C. Postdatism
D. Disseminated Intravascular Coagulation (DIC)

Explanation: ***Eclampsia*** - **Eclampsia** is defined as the occurrence of **generalized tonic-clonic seizures** in a woman with pre-eclampsia that cannot be attributed to other causes - It represents the **direct neurological progression** of pre-eclampsia and is the **most characteristic complication** - Eclampsia occurs in approximately **1-2%** of women with pre-eclampsia and is a **life-threatening emergency** - The seizures result from cerebral vasospasm, edema, and ischemia associated with the hypertensive disorder *HELLP syndrome* - **HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets)** is indeed a **recognized complication** of pre-eclampsia, occurring in **10-20% of severe cases** - However, HELLP represents a **specific multiorgan manifestation** involving hepatic dysfunction and hematological abnormalities, rather than the classic progression pathway - While both are serious complications, **eclampsia** is considered the **prototypical complication** that defines disease progression from pre-eclampsia - HELLP can occur with or without the full clinical picture of severe pre-eclampsia *Postdatism* - **Postdatism** (post-term pregnancy) refers to pregnancy extending beyond **42 weeks of gestation** - This is **completely unrelated** to pre-eclampsia, which is a hypertensive disorder of pregnancy - Pre-eclampsia typically occurs in the **third trimester** and is actually an indication for **delivery**, not prolonged pregnancy *Disseminated Intravascular Coagulation (DIC)* - **DIC** is a severe coagulopathy involving widespread activation of clotting cascades - While DIC can complicate severe pre-eclampsia, it is **not a primary or direct complication** - DIC more commonly develops as a consequence of **eclampsia, HELLP syndrome, placental abruption**, or other severe obstetric emergencies - It represents a **secondary complication** rather than a direct progression of pre-eclampsia itself

Question 1180: Which of the following is NOT a feature of mild or non-severe pre-eclampsia?

A. Diastolic BP <100 mm Hg
B. Systolic BP< 160 mm Hg
C. Premonitory symptoms present (Correct Answer)
D. Mild IUGR

Explanation: ***Premonitory symptoms present*** - The **presence of premonitory symptoms** (such as **severe headache**, **visual disturbances**, **epigastric pain**, or **altered mental status**) is a defining feature of **severe pre-eclampsia**, NOT mild or non-severe pre-eclampsia. - These symptoms indicate impending eclampsia or serious end-organ involvement, which classifies the condition as severe. - This is the correct answer as it is NOT a feature of mild pre-eclampsia. *Diastolic BP <100 mm Hg* - In mild pre-eclampsia, the **diastolic blood pressure** is typically **elevated** (≥90 mmHg) but remains **below 110 mmHg**. - This is a defining characteristic of mild pre-eclampsia, differentiating it from severe pre-eclampsia where diastolic BP is ≥110 mmHg. - This IS a feature of mild pre-eclampsia. *Systolic BP <160 mm Hg* - A **systolic blood pressure** below **160 mmHg** (but ≥140 mmHg) is consistent with mild or non-severe pre-eclampsia. - Severe pre-eclampsia is characterized by a systolic BP of ≥160 mmHg, making this range indicative of milder disease. - This IS a feature of mild pre-eclampsia. *Mild IUGR* - **Mild intrauterine growth restriction (IUGR)** can occur in mild pre-eclampsia due to **placental insufficiency**. - While more severe IUGR is associated with severe pre-eclampsia, mild IUGR can be seen in non-severe cases. - This IS a feature that can occur in mild pre-eclampsia.

Practice by Chapter

Fetal Assessment Techniques

Practice Questions

Hypertensive Disorders in Pregnancy

Practice Questions

Intrauterine Growth Restriction

Practice Questions

Multiple Gestation

Practice Questions

Rh Isoimmunization and Other Blood Group Incompatibilities

Practice Questions

Intrauterine Fetal Therapy

Practice Questions

Prenatal Diagnosis and Genetic Counseling

Practice Questions

Placental Abnormalities

Practice Questions

Preterm Labor and Delivery

Practice Questions

Management of Medical Disorders in Pregnancy

Practice Questions

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free