Endocrinology of Pregnancy — MCQs

Endocrinology of Pregnancy Indian Medical PG Practice Questions and MCQs

Question 251: Which of the following statements about the placenta is correct?

A. The placenta produces estrogen. (Correct Answer)
B. The placenta has 2 arteries and 1 vein.
C. The placental artery carries deoxygenated blood from the fetus to the placenta.
D. Wharton's jelly is found in the umbilical cord.

Explanation: ***The placenta produces estrogen.*** - The **placenta** is an important endocrine organ, producing various hormones including **estrogen** (specifically estriol) and progesterone. - These hormones are crucial for maintaining the pregnancy and supporting fetal development. *The placental artery carries deoxygenated blood from the fetus to the placenta.* - This statement is incorrect as the **umbilical arteries** (not placental arteries) carry **deoxygenated blood and waste products** from the fetus to the placenta. - The **umbilical vein** carries **oxygenated blood and nutrients** from the placenta to the fetus. *The placenta has 2 arteries and 1 vein.* - This describes the typical composition of the **umbilical cord**, not the placenta itself. - The **placenta** is a distinct organ that connects the mother and fetus, facilitating nutrient and gas exchange. *Wharton's jelly is found in the umbilical cord.* - This statement is correct, but the question asks about the **placenta**, not the umbilical cord. - **Wharton's jelly** is a gelatinous substance that protects and supports the blood vessels within the umbilical cord.

Question 252: What percentage of cases of complete vesicular mole is associated with theca lutein cysts?

A. <5%
B. 5-15%
C. 20-40% (Correct Answer)
D. 60-70%

Explanation: ***20-40%*** - **Theca lutein cysts** are benign ovarian cysts that commonly develop in response to excessively high levels of **human chorionic gonadotropin (hCG)**. - In cases of **complete hydatidiform mole**, hCG levels are often very elevated, leading to the development of these cysts in approximately **20-40% of affected women**. *<5%* - This percentage is too low for the incidence of **theca lutein cysts** associated with a complete vesicular mole. - Significant **hCG stimulation** characteristic of molar pregnancies leads to a higher frequency of these ovarian changes compared to normal pregnancies. *5-15%* - While **theca lutein cysts** can occur in pregnancies with high hCG, this range underestimates the prevalence in **complete hydatidiform moles**. - The massive syncytial tissue proliferation in molar pregnancies produces such substantial hCG that the incidence of these cysts is typically considerably higher. *60-70%* - This percentage is too high for the typical incidence of **theca lutein cysts** in complete vesicular moles. - Although the association is significant, it does not occur in the majority of cases; many women with complete moles do not develop clinically relevant theca lutein cysts.

Question 253: At what weeks of gestation does insulin production begin in a fetus?

A. 4-6 weeks
B. 8-12 weeks (Correct Answer)
C. 14-18 weeks
D. 24-28 weeks

Explanation: ***8-12 weeks*** - The **fetal pancreas** begins to develop and differentiate during this period - **Beta cells** differentiate and begin insulin secretion around **9-11 weeks** - While insulin production starts during this timeframe, its levels remain relatively low until later in gestation - This marks the **initiation** of fetal insulin production *4-6 weeks* - This stage is too early for **insulin production**; the pancreas itself is only beginning to form during early organogenesis - The focus during this period is on basic **body plan formation** and early organ development - Beta cell differentiation has not yet begun *14-18 weeks* - By this point, insulin production is **well established** and ongoing - **Fetal insulin** is playing a more significant role in metabolic regulation - Insulin levels are higher than in earlier stages, but the **initiation** of production occurred earlier (8-12 weeks) *24-28 weeks* - At this gestational age, the **fetal pancreas** is well-developed with robust and mature insulin production - Insulin secretion is responsive to glucose levels and plays a key role in **fetal growth** and **fat deposition** - This represents mature regulatory function, not the initiation of insulin production

Question 254: Beta HCG is detected earliest by which day of conception?

A. 8 days (Correct Answer)
B. 15 days
C. 21 days
D. 30 days

Explanation: ***Correct Option: 8 days*** - **Beta-hCG** is produced by the **syncytiotrophoblast** cells of the developing embryo immediately after implantation - Detectable in **maternal serum** as early as **8 days post-conception** (approximately 6-8 days post-implantation) - This corresponds to approximately 22-23 days after the last menstrual period (assuming a 28-day cycle with ovulation on day 14) - **Serum beta-hCG assays** are more sensitive than urine tests and allow for the earliest detection of pregnancy, even before a missed period - This early detection is clinically important for confirming early pregnancy, ectopic pregnancy diagnosis, and monitoring *Incorrect Option: 15 days* - While beta-hCG levels would be significantly higher and more reliably detected by 15 days post-conception, it is not the *earliest* day of detection - At this point, both serum and urine pregnancy tests would yield positive results - This timing is well past the point of initial detectability *Incorrect Option: 21 days* - By 21 days post-conception, beta-hCG levels are very high and pregnancy would be firmly established - This is much later than the earliest possible detection - This timing corresponds to approximately week 5 of gestation (calculated from LMP) *Incorrect Option: 30 days* - Detection at 30 days post-conception is very late for the initial detection of beta-hCG - By this point, pregnancy would be well-established with beta-hCG levels in thousands of mIU/mL - Other clinical signs and symptoms of pregnancy would likely be present

Question 255: Which acid-base derangement is seen in pregnancy?

A. Metabolic acidosis
B. Metabolic alkalosis
C. Respiratory acidosis
D. Respiratory alkalosis (Correct Answer)

Explanation: ***Respiratory alkalosis*** - During pregnancy, **progesterone** stimulates the respiratory drive, leading to an **increase in tidal volume and respiratory rate**. - This hyperventilation causes an excessive exhalation of **carbon dioxide (CO2)**, leading to a decrease in the partial pressure of CO2 (PaCO2) and a compensatory **respiratory alkalosis**. *Metabolic acidosis* - This condition occurs when there is an **excess of acid** or a **loss of bicarbonate** in the body. - It is not a typical physiological change in healthy pregnancies, although it can occur in conditions like **diabetic ketoacidosis** or **lactic acidosis**, which are not normal pregnancy states. *Metabolic alkalosis* - Metabolic alkalosis is characterized by an **increase in bicarbonate** or a **loss of hydrogen ions**. - This is not a normal physiological adaptation during pregnancy; instead, bicarbonate levels are often slightly decreased as a compensation for respiratory alkalosis. *Respiratory acidosis* - This state is caused by **hypoventilation**, leading to an **accumulation of CO2** in the blood. - Pregnancy typically involves **hyperventilation**, making respiratory acidosis an unlikely physiological occurrence.

Question 256: Overt diabetes in pregnancy is defined as fasting blood glucose greater than or equal to which of the following thresholds?

A. >200 mg/dl
B. >126 mg/dl (Correct Answer)
C. >100 mg/dl
D. >180 mg/dl

Explanation: **>126 mg/dl** - **Overt diabetes in pregnancy** (pre-existing diabetes detected during pregnancy) is diagnosed when fasting plasma glucose levels are **≥126 mg/dL**, or when HbA1c is **≥6.5%**, or when random plasma glucose is **≥200 mg/dL** with symptoms of hyperglycemia. - This threshold identifies individuals with pre-existing diabetes or severe hyperglycemia during pregnancy, requiring immediate management and distinction from gestational diabetes mellitus (GDM). *>200 mg/dl* - A random plasma glucose of **≥200 mg/dL** with symptoms is indicative of overt diabetes in pregnancy. - However, for a *fasting* blood glucose threshold for overt diabetes in pregnancy, **126 mg/dL** is the specific cutoff, not 200 mg/dL. *>100 mg/dl* - A fasting glucose of **100-125 mg/dL** in pregnancy falls in the impaired fasting glucose range. - For gestational diabetes mellitus (GDM), the fasting threshold is **≥92 mg/dL**, while for overt diabetes in pregnancy, it is **≥126 mg/dL**. *>180 mg/dl* - While **180 mg/dL** is a significant glucose level and represents the 1-hour OGTT cutoff for GDM, it doesn't align with the specific diagnostic criteria for *fasting* blood glucose in overt diabetes in pregnancy. - The fasting threshold for overt diabetes in pregnancy is **126 mg/dL**.

Question 257: Which of the following statements is correct regarding the functions of the placenta?

A. The placenta secretes insulin for fetal glucose regulation.
B. The placenta produces several hormones including estrogen. (Correct Answer)
C. The umbilical cord contains 2 arteries and 1 vein.
D. The placenta directly transfers maternal blood to the fetus.

Explanation: ***The placenta produces several hormones including estrogen.*** - The placenta acts as a temporary **endocrine organ**, producing various hormones essential for maintaining pregnancy, including **estrogen**, **progesterone**, and **human chorionic gonadotropin (hCG)**. - **Estrogen** contributes to uterine growth, increased blood flow, breast development, and preparation for lactation. - Other placental hormones include **human placental lactogen (hPL)** and **relaxin**. *The placenta secretes insulin for fetal glucose regulation.* - This is **incorrect**. The placenta does NOT produce insulin. - **Insulin** is produced by the **fetal pancreas** (and maternal pancreas for the mother), not by the placenta. - The placenta facilitates glucose transfer but does not regulate it through insulin secretion. *The umbilical cord contains 2 arteries and 1 vein.* - While this statement is anatomically **correct** about umbilical cord structure, it describes the **umbilical cord anatomy**, not the **functions of the placenta**. - The question specifically asks about placental functions, not anatomical structures of associated components. *The placenta directly transfers maternal blood to the fetus.* - This is **incorrect**. Maternal and fetal blood do NOT mix directly. - The placenta maintains **separate circulatory systems** with exchange occurring across the **placental membrane** (barrier). - Nutrients, oxygen, and waste products are exchanged via **diffusion, active transport, and facilitated diffusion** across this barrier, not through direct blood transfer.

Question 258: Which hormone is primarily responsible for insulin resistance during pregnancy?

A. Estrogen
B. HPL (Correct Answer)
C. Progesterone
D. GH

Explanation: ***HPL*** - **Human placental lactogen (HPL)**, also known as **chorionic somatomammotropin**, directly induces maternal insulin resistance to ensure a continuous supply of glucose to the fetus. - HPL levels rise throughout pregnancy, peaking in the third trimester, correlating with increasing insulin resistance. *Estrogen* - While **estrogen** levels are high in pregnancy, its primary role is in supporting uterine growth and maintaining the pregnancy, not directly causing significant insulin resistance. - High estrogen levels can enhance insulin sensitivity in some contexts, contrasting with the overall insulin resistance of pregnancy. *Progesterone* - **Progesterone** is crucial for maintaining pregnancy and relaxing smooth muscle but does not directly cause the marked insulin resistance seen in gestation. - It works synergistically with other hormones but is not the primary driver of glucose intolerance in pregnancy. *GH* - **Growth hormone (GH)** does contribute to insulin resistance in non-pregnant individuals and at high levels can cause insulin resistance, but it is not the primary hormone responsible for the unique physiological insulin resistance of pregnancy. - While GH is present, **HPL** is the dominant somatotropic hormone of pregnancy directly impacting glucose metabolism.

Question 259: What is the primary maternal cause of fetal macrosomia (large birth weight) in newborns?

A. Hyperglycemia (Correct Answer)
B. Hyperinsulinemia
C. Multiparity
D. Post maturity

Explanation: ***Hyperglycemia*** - Maternal **hyperglycemia**, often due to **gestational diabetes**, leads to increased glucose transfer across the placenta to the fetus. - This excess glucose stimulates increased fetal insulin production, which acts as a growth hormone causing macrosomia. *Hyperinsulinemia* - While fetal **hyperinsulinemia** directly causes macrosomia by increasing fetal growth, it is a **consequence** of maternal hyperglycemia, not the primary cause itself. - Fetal insulin acts as an anabolic hormone, promoting fat and protein synthesis and overall growth. *Multiparity* - **Multiparity** (having given birth to multiple children) is generally associated with moderately higher birth weights, but it is not the primary cause of macrosomia. - The effect is far less significant and consistent than that of maternal hyperglycemia. *Post maturity* - **Post-term pregnancy** (post maturity) can sometimes be associated with a larger birth weight, but this is less common and less pronounced than macrosomia caused by hyperglycemia. - Fetal growth often slows or even declines in prolonged pregnancies due to placental insufficiency.

Question 260: Which of the following statements about gestational diabetes mellitus (GDM) is true?

A. It is always associated with a previous history of IUGR.
B. There is no recurrence of GDM in future pregnancies.
C. There is no risk of developing overt diabetes in the future.
D. Gestational diabetes mellitus is first recognized during pregnancy. (Correct Answer)

Explanation: ***Gestational diabetes mellitus is first recognized during pregnancy.*** - GDM is defined as **glucose intolerance** that is first recognized or diagnosed during pregnancy, regardless of whether it requires insulin or persists after pregnancy. - This definition distinguishes it from **pre-existing type 1 or type 2 diabetes** diagnosed before conception. *It is always associated with a previous history of IUGR.* - GDM is primarily associated with an increased risk of **macrosomia** (large-for-gestational-age babies) due to high maternal glucose levels stimulating fetal insulin production and growth. - While other pregnancy complications can occur, **intrauterine growth restriction (IUGR)** is not a typical or consistent association with GDM. *There is no recurrence of GDM in future pregnancies.* - Women who have had GDM in one pregnancy have a **significantly increased risk** (30-50%) of developing it again in subsequent pregnancies. - This recurrence risk highlights the underlying predisposition to glucose intolerance. *There is no risk of developing overt diabetes in the future.* - A history of GDM is a strong predictor for developing **type 2 diabetes** later in life, with up to 50% of women developing it within 5-10 years post-delivery. - It also carries a small increased risk of developing **type 1 diabetes** in some individuals.

Practice by Chapter

Endocrine Changes in Normal Pregnancy

Practice Questions

Thyroid Disorders in Pregnancy

Practice Questions

Diabetes in Pregnancy

Practice Questions

Adrenal Disorders in Pregnancy

Practice Questions

Pituitary Disorders in Pregnancy

Practice Questions

Hyperemesis Gravidarum

Practice Questions

Hormonal Regulation of Labor

Practice Questions

Pharmacokinetics of Hormones in Pregnancy

Practice Questions

Fetal Endocrine Development

Practice Questions

Placental Hormones

Practice Questions

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