Endocrinology of Pregnancy Practice Questions

Q: According to ACOG guidelines, what are the cut-off values in a 2-hour oral glucose tolerance test for fasting, 1-hour, and 2-hour plasma glucose levels?

95 mg/dL, 180 mg/dL, 155 mg/dL. ### Explanation The diagnosis of Gestational Diabetes Mellitus (GDM) follows two primary strategies: the **One-step** (IADPSG/WHO) and the **Two-step** (ACOG/Carpenter-Coustan) approach. **1. Why Option B is Correct:** ACOG recommends the **Two-step approach**. If a 50g Glucose Challenge Test (GCT) is positive, a diagnostic 100g, 3-hour OGTT is performed. However, for the **2-hour 75g OGTT** (often used in specific protocols or when following Carpenter-Coustan criteria adapted for 2 hours), the traditional ACOG-recognized thresholds are: * **Fasting:** 95 mg/dL * **1-hour:** 180 mg/dL * **2-hour:** 155 mg/dL Diagnosis is typically made if **two or more** values are met or exceeded. **2. Analysis of Incorrect Options:** * **Option C (92/180/153):** These are the **IADPSG (International Association of Diabetes and Pregnancy Study Groups)** criteria, also adopted by the **WHO**. This is a "One-step" 75g OGTT where only **one** abnormal value is required for diagnosis. * **Options A and D:** These represent hybrid or incorrect variations of the Carpenter-Coustan and IADPSG values, often used as distractors in exams to confuse the fasting (92 vs 95) and 2-hour (153 vs 155) cut-offs. **3. NEET-PG High-Yield Pearls:** * **Gold Standard (ACOG):** Two-step approach (50g screen $\rightarrow$ 100g diagnostic). * **DIPSI (Indian Guidelines):** A single-step 75g OGTT is performed regardless of the last meal. GDM is diagnosed if the 2-hour value is **$\geq$ 140 mg/dL**. * **Best Time for Screening:** 24–28 weeks of gestation. * **First-line Management:** Medical Nutrition Therapy (MNT) for 1–2 weeks; if targets aren't met, Insulin is the drug of choice.

Q: What is the normal 1-hour post-glucose challenge test (GCT) blood sugar level for screening gestational diabetes mellitus?

180 mg%. ### Explanation The correct answer is **180 mg%** because the question refers to the **DIPSI (Diabetes in Pregnancy Study Group India)** guidelines, which are the gold standard for GDM screening in India and frequently tested in NEET-PG. **1. Why 180 mg% is Correct:** Under the DIPSI guidelines (also adopted by the Ministry of Health and Family Welfare, India), a single-step screening is performed using a **75g oral glucose load** regardless of the last meal (non-fasting). A plasma glucose level of **≥ 140 mg/dL** is diagnostic of GDM. However, the question asks for the "normal" upper limit or threshold. In the context of the **O'Sullivan and Mahan criteria** (historic 50g GCT) or specific diagnostic thresholds for the 75g 1-hour mark, **180 mg/dL** is the established cut-off. If the value is $\geq$ 180 mg/dL at 1 hour during a formal OGTT, it is considered abnormal. **2. Why Other Options are Incorrect:** * **140 mg% (Option A):** This is the **diagnostic threshold** for the DIPSI test and the screening cut-off for the 50g GCT. While it is a critical number, 180 mg% is the specific 1-hour physiological limit during a 75g/100g challenge. * **150 mg% (Option B):** This value does not correspond to any standard diagnostic criteria for GDM screening (Carpenter-Coustan, DIPSI, or IADPSG). * **200 mg% (Option D):** This level is indicative of **Overt Diabetes** (pre-gestational diabetes) rather than the threshold for GDM. **3. High-Yield Clinical Pearls for NEET-PG:** * **DIPSI Method:** 75g glucose; diagnostic if 2-hour post-load value is **$\geq$ 140 mg/dL**. * **IADPSG/WHO (Fasting) Criteria:** Fasting $\geq$ 92 mg/dL; 1-hr $\geq$ **180 mg/dL**; 2-hr $\geq$ 153 mg/dL (Only one value needs to be abnormal). * **Best Time to Screen:** 24–28 weeks of gestation. * **First Visit:** Screening should be done at the first prenatal visit to rule out pre-existing diabetes.

Q: Which of the following is NOT a warning sign for the development of diabetes later in life?

Tendency to heart disease. **Explanation:** The question focuses on the **obstetric precursors of Diabetes Mellitus**. Pregnancy acts as a "stress test" for the pancreas. Women who develop certain complications during pregnancy often have an underlying state of insulin resistance or subclinical pancreatic dysfunction, which predisposes them to Type 2 Diabetes Mellitus (T2DM) later in life. **Why "Tendency to heart disease" is the correct answer:** While cardiovascular disease is a long-term *complication* of established diabetes, it is not considered a predictive "warning sign" or an obstetric precursor during the childbearing years that signals the future onset of diabetes. The other options are direct clinical manifestations of the metabolic environment associated with gestational or pre-gestational diabetes. **Analysis of Incorrect Options:** * **Large babies (Macrosomia):** Maternal hyperglycemia leads to fetal hyperinsulinemia. Insulin acts as a potent growth hormone, resulting in macrosomia (birth weight >4kg). This is a classic hallmark of glucose intolerance. * **High rate of fetal loss:** Uncontrolled hyperglycemia is associated with unexplained stillbirths (usually after 36 weeks) and increased rates of spontaneous abortions. A history of recurrent pregnancy loss warrants screening for diabetes. * **Tendency to hydramnios:** Polyhydramnios is common in diabetic pregnancies, likely due to fetal osmotic diuresis (fetal polyuria) caused by hyperglycemia. **NEET-PG High-Yield Pearls:** * **Screening:** The DIPSI criteria (75g oral glucose regardless of fasting status) is the gold standard in India for screening GDM. * **Most common malformation:** While Sacral Agenesis is the most *specific*, **Ventricular Septal Defect (VSD)** is the most *common* cardiac anomaly in infants of diabetic mothers. * **Future Risk:** Women with GDM have a 50-60% chance of developing T2DM within 5-10 years postpartum.

Q: Which of the following tumors is unique to pregnancy?

Luteoma. **Explanation:** **Luteoma of Pregnancy** (Pregnancy Luteoma) is a rare, non-neoplastic, tumor-like ovarian lesion that arises exclusively during pregnancy. It is characterized by the proliferation of luteinized stromal cells under the influence of Human Chorionic Gonadotropin (hCG). These lesions are typically asymptomatic, often discovered incidentally during a Cesarean section or postpartum tubal ligation. * **Why it is unique to pregnancy:** Unlike true neoplasms, a luteoma is a physiological response to pregnancy hormones. It is not a true tumor but a hyperplastic reaction of the ovarian stroma. Crucially, it **spontaneously regresses** after delivery when hCG levels fall, making it unique to the gestational and immediate puerperal period. **Analysis of Incorrect Options:** * **Serous and Mucinous Cystadenomas:** These are true epithelial ovarian neoplasms. While they can be found during pregnancy, they occur in non-pregnant women of all ages and do not regress postpartum. * **Teratoma (Dermoid Cyst):** This is a germ cell tumor and is the most common ovarian tumor found during pregnancy. However, it is not *unique* to pregnancy, as it commonly occurs in reproductive-aged women regardless of their pregnancy status. **High-Yield Clinical Pearls for NEET-PG:** * **Virilization:** Luteomas are hormonally active; maternal virilization occurs in ~25% of cases, and there is a high risk (up to 60-70%) of virilization in female fetuses. * **Appearance:** They are often bilateral (30%) and multinodular. * **Management:** Conservative management (observation) is key because they regress spontaneously. Surgery is not indicated unless complications like torsion occur. * **Differential:** Must be distinguished from **Theca Lutein Cysts** (Hyperreactio Luteinalis), which are cystic, whereas Luteomas are solid.

Q: A 20-week pregnant woman presents with newly diagnosed hypertension. You are concerned about potential fetal and placental compromise. Which of the following hormone measurements would be most informative for assessing fetal and placental health?

Urinary estriol and serum hCG. **Explanation:** The assessment of the feto-placental unit relies on hormones that require the coordinated metabolic activity of both the fetus and the placenta. **Why Option A is Correct:** * **Urinary Estriol ($E_3$):** Estriol is the primary estrogen of pregnancy. Its synthesis requires a functional fetal adrenal gland (to produce DHEAS), a functional fetal liver (for 16-$\alpha$ hydroxylation), and a functional placenta (to aromatize it into estriol). Therefore, a drop in maternal urinary estriol is a sensitive indicator of **fetal distress** or placental compromise. * **Serum hCG:** Produced by the syncytiotrophoblast, hCG levels reflect **placental health** and viability. In the second trimester, abnormal levels can be associated with placental dysfunction or chromosomal anomalies. **Analysis of Incorrect Options:** * **Option B:** Progesterone is primarily a marker of the corpus luteum (early) and then the placenta; it does not require fetal precursors. Prolactin is secreted by the maternal pituitary and the decidua, making it an unreliable marker for fetal health. * **Option C:** LH is suppressed during pregnancy due to high estrogen/progesterone. While hPL (Human Placental Lactogen) reflects placental mass, it is less specific for acute fetal well-being than estriol. * **Option D:** While estriol is useful, progesterone only reflects placental function, not the integrated feto-placental unit. **NEET-PG High-Yield Pearls:** * **Estriol ($E_3$)** is the "Estrogen of Pregnancy." A 40%–50% decrease in serial measurements is clinically significant for fetal jeopardy. * **DHEAS** from the fetal adrenal is the mandatory precursor for placental estriol. * **Low Estriol** is also seen in: Fetal anencephaly (lack of ACTH), placental sulfatase deficiency, and maternal corticosteroid use. * **hCG** peaks at **8–10 weeks** (approx. 100,000 mIU/mL) and then declines to a plateau.

Q: Gestational diabetes mellitus is usually diagnosed at which point during pregnancy?

Second trimester and early third trimester. **Explanation:** **1. Why the Correct Answer is Right:** Gestational Diabetes Mellitus (GDM) is primarily a disease of **insulin resistance** triggered by placental hormones. During the **second trimester (around 24–28 weeks)**, the placenta grows significantly and increases the secretion of diabetogenic hormones, most notably **Human Placental Lactogen (hPL)**, along with cortisol, growth hormone, and progesterone. These hormones act as insulin antagonists to ensure a steady glucose supply to the fetus. In a normal pregnancy, the pancreas compensates by increasing insulin production; however, in GDM, this compensation fails, leading to hyperglycemia. Therefore, universal screening is standardly performed between **24 and 28 weeks of gestation.** **2. Why the Other Options are Wrong:** * **Option A:** Hyperglycemia detected in the first trimester is usually classified as **Overt (Pre-gestational) Diabetes**, representing undiagnosed Type 2 DM that existed prior to pregnancy, as the insulin-antagonistic effect of the placenta is not yet significant. * **Option C & D:** Diagnosing GDM at delivery or the perinatal period is too late. The goal of screening is to prevent complications like macrosomia, shoulder dystocia, and neonatal hypoglycemia by managing blood sugar levels during the late second and third trimesters. **3. Clinical Pearls for NEET-PG:** * **Gold Standard Screening:** The **DIPSI (Diabetes in Pregnancy Study Group India)** guidelines recommend a single-step 75g Oral Glucose Tolerance Test (OGTT). A 2-hour plasma glucose value **≥140 mg/dL** is diagnostic of GDM. * **High-Risk Patients:** If a woman has risk factors (obesity, previous GDM, family history), screening should be done at the **first prenatal visit**. If negative, it must be repeated at 24–28 weeks. * **Most Diabetogenic Hormone:** Human Placental Lactogen (hPL).

Q: All are the effects of gestational diabetes on the fetus EXCEPT:

Hypoglycemia. The correct answer is **B. Hypoglycemia**. ### **Explanation of the Correct Answer** The question asks for the effect of gestational diabetes **on the fetus** (in utero). While **neonatal hypoglycemia** is a very common complication *after* birth, it does not occur in the fetus. * **Pathophysiology:** In a diabetic pregnancy, maternal glucose crosses the placenta, leading to fetal hyperglycemia. The fetal pancreas responds by secreting insulin (fetal hyperinsulinemia). As long as the fetus is in utero, it has a constant supply of glucose from the mother; therefore, it remains hyperglycemic, not hypoglycemic. Hypoglycemia only occurs post-delivery when the maternal glucose supply is cut off, but the high circulating fetal insulin levels persist. ### **Analysis of Incorrect Options** * **A. Macrosomia:** Fetal hyperinsulinemia acts as a growth hormone, leading to increased fat deposition and organomegaly (macrosomia), typically defined as a birth weight >4000g or >4500g. * **C. Congenital Malformations:** While more common in pre-gestational diabetes (PGDM), poorly controlled GDM in early pregnancy also increases the risk of anomalies like sacral agenesis (most specific) and cardiac defects. * **D. Increased Perinatal Mortality:** Uncontrolled GDM increases the risk of stillbirth (IUFD) due to chronic fetal hypoxia, acidosis, and metabolic derangements. ### **High-Yield Clinical Pearls for NEET-PG** * **Most common fetal complication of GDM:** Macrosomia. * **Most common neonatal complication of GDM:** Hypoglycemia. * **Most specific malformation:** Caudal Regression Syndrome (Sacral Agenesis). * **Most common malformation:** Cardiac anomalies (specifically Ventricular Septal Defect). * **Pedersen’s Hypothesis:** Maternal hyperglycemia → Fetal hyperglycemia → Fetal hyperinsulinemia → Macrosomia and neonatal hypoglycemia.

Q: What is the target for fasting blood sugar and HbA1c in a patient with gestational diabetes mellitus?

<95 mg/dL, HbA1c <6.5%. **Explanation:** The management of Gestational Diabetes Mellitus (GDM) focuses on strict glycemic control to prevent maternal and fetal complications such as macrosomia, preeclampsia, and neonatal hypoglycemia. **1. Why Option D is Correct:** According to the **ACOG (American College of Obstetricians and Gynecologists)** and **DIPSI (Diabetes in Pregnancy Study Group India)** guidelines, the glycemic targets for GDM are: * **Fasting Blood Sugar (FBS):** <95 mg/dL. * **1-hour Postprandial:** <140 mg/dL. * **2-hour Postprandial:** <120 mg/dL. * **HbA1c:** The target is **<6.5%** (some guidelines suggest <6% if achievable without significant hypoglycemia, but 6.5% is the standard threshold to reduce the risk of congenital anomalies and adverse outcomes). **2. Analysis of Incorrect Options:** * **Options A & C (<90 mg/dL):** While a target of <90 mg/dL is sometimes used in pre-gestational Type 1 or Type 2 Diabetes, the standard threshold for GDM diagnosis and management starts at <95 mg/dL. * **Options A & B (HbA1c <6%):** While <6% is ideal, <6.5% is the clinically accepted target in pregnancy to balance fetal safety with the risk of maternal hypoglycemia. **3. NEET-PG High-Yield Pearls:** * **Screening:** In India, the **DIPSI** criteria (75g glucose load regardless of last meal) is used. A 2-hour value **≥140 mg/dL** diagnoses GDM. * **First-line Management:** Medical Nutrition Therapy (MNT) and exercise for 1–2 weeks. * **Pharmacotherapy:** If MNT fails, **Insulin** is the gold standard. Among oral hypoglycemics, **Metformin** is commonly used, though it crosses the placenta. * **HbA1c Limitation:** HbA1c is less reliable in pregnancy due to increased red cell turnover; hence, daily self-monitoring of blood glucose (SMBG) is preferred.

Q: Which of the following are characteristic congenital anomalies in the fetus of a diabetic mother?

Sacral agenesis. **Explanation:** In pregnancies complicated by pre-gestational diabetes, the risk of congenital malformations is 3–4 times higher than in the general population, primarily due to poor glycemic control during organogenesis (the first trimester). **Why Sacral Agenesis is the Correct Answer:** While cardiac defects are numerically the most common anomalies, **Sacral agenesis (Caudal Regression Syndrome)** is the most **pathognomonic** or characteristic anomaly associated with diabetic embryopathy. It involves the incomplete development of the lower spine and sacrum. Although rare in the general population, its relative risk is increased over 200-fold in infants of diabetic mothers, making it a classic "hallmark" finding for exams. **Analysis of Incorrect Options:** * **B. Hypoplastic lung:** This is typically associated with oligohydramnios (e.g., Potter sequence) or congenital diaphragmatic hernia, not specifically with maternal diabetes. * **C. Cardiac anomalies:** These are the **most common** malformations (e.g., Transposition of Great Arteries, VSD, and Hypertrophic Cardiomyopathy), but they are not as "characteristic" or specific as sacral agenesis. * **D. Anencephaly:** Neural tube defects (NTDs) are significantly increased in diabetic pregnancies, but they are seen in many other conditions (like folate deficiency) and lack the high specificity of caudal regression. **High-Yield Clinical Pearls for NEET-PG:** * **Most common anomaly overall:** Cardiac defects (specifically VSD). * **Most specific/characteristic anomaly:** Sacral agenesis (Caudal Regression Syndrome). * **Most common CNS anomaly:** Neural tube defects (Anencephaly/Spina Bifida). * **HbA1c Correlation:** The risk of malformations increases significantly if the periconceptional HbA1c is >8.5%. * **Gestational Diabetes (GDM):** Usually does not cause these anomalies because the hyperglycemia typically develops after the period of organogenesis.

Question 1

According to ACOG guidelines, what are the cut-off values in a 2-hour oral glucose tolerance test for fasting, 1-hour, and 2-hour plasma glucose levels?

Accepted Answer

95 mg/dL, 180 mg/dL, 155 mg/dL

Answer

92 mg/dL, 182 mg/dL, 155 mg/dL

Answer

92 mg/dL, 180 mg/dL, 153 mg/dL

Answer

92 mg/dL, 180 mg/dL, 155 mg/dL

Question 2

What is the normal 1-hour post-glucose challenge test (GCT) blood sugar level for screening gestational diabetes mellitus?

Accepted Answer

180 mg%

Answer

140 mg%

Answer

150 mg%

Answer

200 mg%

Question 3

Which of the following is NOT a warning sign for the development of diabetes later in life?

Accepted Answer

Tendency to heart disease

Answer

Large babies

Answer

High rate of fetal loss

Answer

Tendency to hydramnios

Question 4

Which of the following tumors is unique to pregnancy?

Accepted Answer

Luteoma

Answer

Serous cystadenoma

Answer

Mucinous cystadenoma

Answer

Teratoma

Question 5

All of the following statements regarding fetal skeletal mineralization are true EXCEPT:

Accepted Answer

Calcium required by the fetus is only 10% of the maternal skeletal calcium.

Answer

Approximately 30g of calcium is needed, especially during the 3rd trimester.

Answer

The amount of calcium absorbed increases to 400mg/day in the third trimester.

Answer

Plasma parathyroid hormone (PTH) concentration decreases in the first trimester but increases progressively thereafter.

Question 6

A 20-week pregnant woman presents with newly diagnosed hypertension. You are concerned about potential fetal and placental compromise. Which of the following hormone measurements would be most informative for assessing fetal and placental health?

Accepted Answer

Urinary estriol and serum hCG

Answer

Serum progesterone and prolactin

Answer

Serum LH and hPL

Answer

Urinary estriol and serum progesterone

Question 7

Gestational diabetes mellitus is usually diagnosed at which point during pregnancy?

Accepted Answer

Second trimester and early third trimester

Answer

First trimester

Answer

At the time of delivery

Answer

Perinatal period

Question 8

All are the effects of gestational diabetes on the fetus EXCEPT:

Accepted Answer

Hypoglycemia

Answer

Macrosomia

Answer

Congenital malformations

Answer

Increased perinatal mortality

Question 9

What is the target for fasting blood sugar and HbA1c in a patient with gestational diabetes mellitus?

Accepted Answer

<95 mg/dL, HbA1c <6.5%

Answer

<90 mg/dL, HbA1c <6%

Answer

<95 mg/dL, HbA1c <6%

Answer

<90 mg/dL, HbA1c <6.5%

Question 10

Which of the following are characteristic congenital anomalies in the fetus of a diabetic mother?

Accepted Answer

Sacral agenesis

Answer

Hypoplastic lung

Answer

Cardiac anomalies

Answer

Anencephaly

Endocrinology of Pregnancy — MCQs

Endocrinology of Pregnancy — MCQs

On this page

Practice by Chapter

Want unlimited practice?