A 36-year-old woman, gravida 2, para 1, at 30 weeks' gestation comes to the physician for evaluation of increased urinary frequency. She has no history of major medical illness. Physical examination shows no abnormalities. Laboratory studies show an increased serum C-peptide concentration. Ultrasonography shows polyhydramnios and a large for gestational age fetus. Which of the following hormones is predominantly responsible for the observed laboratory changes in this patient?
Q122
A 36-year-old G2-P1 woman in week 33 of gestation presents to the emergency department in acute respiratory distress. She works as a secretary for a local law firm, and she informs you that she recently returned from a trip to the beach. She currently smokes half-a-pack of cigarettes/day, drinks 1 glass of red wine/day, and she endorses a past history of injection drug use but currently denies any illicit drug use. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 87/min, and respiratory rate 23/min. Her physical examination shows minimal bibasilar rales, but otherwise clear lungs on auscultation, grade 2/6 holosystolic murmur, and a gravid uterus with no obvious abnormalities. A D-dimer is found to be elevated, and her V/Q scan reveals a high probability of pulmonary embolism (PE). Her medical history is significant for uterine fibroids, preeclampsia, hypercholesterolemia, diabetes mellitus type 1, and significant for heparin-induced thrombocytopenia. Which of the following is the most appropriate choice of management for her post-acute care?
Q123
A 27-year-old Hispanic G2P1 presents for a routine antepartum visit at 26 weeks gestation. She has no complaints. The vital signs are normal, the physical examination is within normal limits, and the gynecologic examination corresponds to 25 weeks gestation. The oral glucose tolerance test (OGTT) with a 75-g glucose load is significant for a glucose level of 177 mg/dL at 1 hour and 167 mg/dL at 2 hour. The fasting blood glucose level is 138 mg/dL (7.7 mmol/L), and the HbA1c is 7%. Which of the following represents the proper initial management?
Q124
A 36-year-old G4P3 is admitted to the obstetrics floor at 35 weeks gestation with painless vaginal spotting for a week. She had 2 cesarean deliveries. An ultrasound examination at 22 weeks gestation showed a partial placenta previa, but she was told not to worry. Today, her vital signs are within normal limits, and a physical examination is unremarkable, except for some blood traces on the perineum. The fetal heart rate is 153/min. The uterine fundus is at the xiphoid process and uterine contractions are absent. Palpation identifies a longitudinal lie. Transvaginal ultrasound shows an anterior placement of the placenta with a placental edge-to-internal os distance of 1.5 cm and a loss of the retroplacental space. Which of the following statements best describes the principle of management for this patient?
Q125
A 22-year-old nulligravid woman comes to the physician for evaluation of irregular periods. Menarche was at the age of 12 years. Her menses have always occurred at variable intervals, and she has spotting between her periods. Her last menstrual period was 6 months ago. She has diabetes mellitus type 2 and depression. She is not sexually active. She drinks 3 alcoholic drinks on weekends and does not smoke. She takes metformin and sertraline. She appears well. Her temperature is 37°C (98.6°F), pulse is 82/min, respirations are 15/min, and blood pressure is 118/75 mm Hg. BMI is 31.5 kg/m2. Physical exam shows severe cystic acne on her face and back. There are dark, velvet-like patches on the armpits and neck. Pelvic examination is normal. A urine pregnancy test is negative. Which of the following would help determine the cause of this patient's menstrual irregularities?
Q126
A 32-year-old G2P0A1 woman presents at 36 weeks of gestation for the first time during her pregnancy. The patient has no complaints, currently. However, her past medical history reveals seizure disorder, which is under control with valproic acid and lithium. She has not seen her neurologist during the past 2 years, in the absence of any complaints. She also reports a previous history of elective abortion. The physical examination is insignificant. Her blood pressure is 130/75 mm Hg and pulse is 80/min. The patient is scheduled to undergo regular laboratory tests and abdominal ultrasound. Given her past medical history, which of the following conditions is her fetus most likely going to develop?
Q127
A 23-year-old primigravida presents to her physician’s office at 12 weeks gestation complaining of increased sweating and palpitations for the last week. She does not have edema or dyspnea, and had no pre-existing illnesses. The patient says that the symptoms started a few days after several episodes of vomiting. She managed the vomiting at home and yesterday the vomiting stopped, but the symptoms she presents with are persistent. The pre-pregnancy weight was 54 kg (119 lb). The current weight is 55 kg (121 lb). The vital signs are as follows: blood pressure 130/85 mm Hg, heart rate 113/min, respiratory rate 15/min, and temperature 37.0℃ (98.6℉). The physical examination is significant for diaphoresis, an irregular heartbeat, and a fine resting tremor of the hands. The neck is not enlarged and the thyroid gland is not palpable. The ECG shows sinus tachyarrhythmia. The thyroid panel is as follows:
Thyroid stimulating hormone (TSH) < 0.1 mU/L
Total T4 178 nmol/L
Free T4 31 pmol/L
Which of the following is indicated?
Q128
A 27-year-old pregnant woman presents to an obstetrician at 35 weeks gestation reporting that she noted the presence of a mucus plug in her vaginal discharge this morning. The obstetrician performs an examination and confirms that she is in labor. She was diagnosed with HIV infection 1 year ago. Her current antiretroviral therapy includes abacavir, lamivudine, and nevirapine. Her last HIV RNA level was 2,000 copies/mL 3 weeks ago. Which of the following anti-retroviral drugs should be administered intravenously to the woman during labor?
Q129
A 36-year-old woman, gravida 3, para 2, at 37 weeks' gestation comes to the emergency department because of sparse vaginal bleeding for 3 hours. She also noticed the bleeding 3 days ago. She has had no prenatal care. Both of her previous children were delivered by lower segment transverse cesarean section. Her temperature is 37.1°C (98.8°F), pulse is 90/min, respirations are 16/min, and blood pressure is 110/80 mm Hg. The abdomen is nontender, and no contractions are felt. Examination shows that the fetus is in a vertex presentation. The fetal heart rate is 160/min and shows no abnormalities. Which of the following is the most appropriate next step in management?
Q130
A 16-year-old girl is brought to the physician because she has not yet had her 1st period. She was born at 39 weeks gestation via spontaneous vaginal delivery. She is up to date on all vaccines and meeting all developmental milestones. She has no history of a serious illness and takes no medications. Physical examination shows underdeveloped breasts with scant pubic and axillary hair. Speculum examination shows a short vagina and no cervix. The remainder of the physical examination shows no abnormalities. Pelvic ultrasound shows no uterus. Which of the following is the most likely karyotype in this patient?
High-risk pregnancies US Medical PG Practice Questions and MCQs
Question 121: A 36-year-old woman, gravida 2, para 1, at 30 weeks' gestation comes to the physician for evaluation of increased urinary frequency. She has no history of major medical illness. Physical examination shows no abnormalities. Laboratory studies show an increased serum C-peptide concentration. Ultrasonography shows polyhydramnios and a large for gestational age fetus. Which of the following hormones is predominantly responsible for the observed laboratory changes in this patient?
A. Human placental lactogen (Correct Answer)
B. Adrenocorticotropic hormone
C. Human chorionic gonadotropin
D. Progesterone
E. Estrogen
Explanation: ***Human placental lactogen***
- **Human placental lactogen (hPL)**, also known as **chorionic somatomammotropin**, is produced by the placenta and has **anti-insulin effects**, increasing maternal blood glucose to prioritize fetal nutrient supply.
- This **insulin resistance** leads to increased maternal insulin production (reflected by **elevated C-peptide**) to compensate, and if inadequate, results in **gestational diabetes mellitus (GDM)**, which explains the **polyhydramnios** and **large for gestational age fetus**.
*Adrenocorticotropic hormone*
- **ACTH** stimulates the **adrenal cortex** to produce **cortisol**, which also has diabetogenic effects.
- However, **hPL** is the primary hormone responsible for the **insulin resistance** of pregnancy and the associated elevated C-peptide and GDM features (polyhydramnios and large for gestational age fetus) in this context.
*Human chorionic gonadotropin*
- **hCG** is crucial for maintaining the **corpus luteum** in early pregnancy, stimulating **progesterone** production, and is used as a marker for pregnancy.
- It does not directly cause the **insulin resistance** or significantly elevate C-peptide that leads to the observed findings of **polyhydramnios** and a **large for gestational age fetus**.
*Progesterone*
- **Progesterone** is essential for maintaining pregnancy by promoting **endometrial growth** and suppressing uterine contractions.
- While it plays a role in some metabolic changes during pregnancy, it is not the primary hormone responsible for the **insulin-antagonistic effects** that lead to the elevated C-peptide and signs of GDM described.
*Estrogen*
- **Estrogen** promotes uterine growth, maintains the **endometrium**, and plays a role in fetal development and the development of maternal secondary sexual characteristics.
- While it contributes to metabolic changes in pregnancy, it is not the main hormone responsible for the **insulin resistance** and related features like elevated C-peptide, polyhydramnios, and a large for gestational age fetus seen in this patient.
Question 122: A 36-year-old G2-P1 woman in week 33 of gestation presents to the emergency department in acute respiratory distress. She works as a secretary for a local law firm, and she informs you that she recently returned from a trip to the beach. She currently smokes half-a-pack of cigarettes/day, drinks 1 glass of red wine/day, and she endorses a past history of injection drug use but currently denies any illicit drug use. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 87/min, and respiratory rate 23/min. Her physical examination shows minimal bibasilar rales, but otherwise clear lungs on auscultation, grade 2/6 holosystolic murmur, and a gravid uterus with no obvious abnormalities. A D-dimer is found to be elevated, and her V/Q scan reveals a high probability of pulmonary embolism (PE). Her medical history is significant for uterine fibroids, preeclampsia, hypercholesterolemia, diabetes mellitus type 1, and significant for heparin-induced thrombocytopenia. Which of the following is the most appropriate choice of management for her post-acute care?
A. Initiate long term heparin
B. Initiate warfarin
C. Consult IR for IVC filter placement (Correct Answer)
D. Initiate apixaban
E. Initiate fondaparinux
Explanation: ***Consult IR for IVC filter placement***
- This patient has a **pulmonary embolism (PE)**, a past medical history of **heparin-induced thrombocytopenia (HIT)**, and is currently in her **third trimester of pregnancy**. Anticoagulation is contraindicated in patients with a history of HIT and pregnancy.
- An **inferior vena cava (IVC) filter** is indicated for patients with acute venous thromboembolism (VTE) who have a contraindication to anticoagulation (e.g., active bleeding, HIT).
*Initiate long term heparin*
- This patient has a history of **heparin-induced thrombocytopenia (HIT)**, which is an absolute contraindication to the use of heparin, including low molecular weight heparin (LMWH) and unfractionated heparin.
- Heparin can trigger a severe prothrombotic state in patients with a history of HIT, leading to limb ischemia, organ damage, or death.
*Initiate warfarin*
- **Warfarin is teratogenic** and is contraindicated throughout pregnancy, particularly during the first trimester.
- Although the risk is lower in the third trimester, it can still cause **fetal bleeding** and is typically avoided if other options exist.
*Initiate apixaban*
- **Apixaban is a direct oral anticoagulant (DOAC)**, and its safety and efficacy in pregnancy are not well-established.
- DOACs are generally **not recommended during pregnancy** due to limited data and potential risks to the fetus.
*Initiate fondaparinux*
- **Fondaparinux** is an **indirect factor Xa inhibitor** that can be used as an alternative anticoagulant in patients with acute VTE who cannot tolerate heparin.
- However, its safety in pregnancy and in patients with a history of HIT is **less established compared to IVC filters** when anticoagulation is absolutely contraindicated.
Question 123: A 27-year-old Hispanic G2P1 presents for a routine antepartum visit at 26 weeks gestation. She has no complaints. The vital signs are normal, the physical examination is within normal limits, and the gynecologic examination corresponds to 25 weeks gestation. The oral glucose tolerance test (OGTT) with a 75-g glucose load is significant for a glucose level of 177 mg/dL at 1 hour and 167 mg/dL at 2 hour. The fasting blood glucose level is 138 mg/dL (7.7 mmol/L), and the HbA1c is 7%. Which of the following represents the proper initial management?
A. Sitagliptin
B. Dietary and lifestyle modification
C. Metformin
D. Glyburide
E. Insulin (Correct Answer)
Explanation: **Insulin**
- The patient's **fasting glucose of 138 mg/dL** and **HbA1c of 7%** indicate pre-existing **Type 2 Diabetes Mellitus**, not just gestational diabetes. Both values exceed the diagnostic thresholds for overt diabetes in pregnancy.
- **Insulin** is the preferred initial pharmacologic treatment for **overt diabetes in pregnancy** because it does not cross the placenta, ensuring fetal safety, and is highly effective in controlling maternal glucose levels.
*Sitagliptin*
- **Sitagliptin** is a **DPP-4 inhibitor** and is not recommended during pregnancy due to limited safety data and the availability of safer alternatives.
- Oral hypoglycemic agents are generally avoided as first-line therapy for established diabetes in pregnancy due to potential for placental transfer and adverse fetal effects.
*Dietary and lifestyle modification*
- While crucial, **dietary and lifestyle modification** alone are insufficient for managing overt diabetes with such high fasting glucose and HbA1c levels.
- These measures are usually the first step for **gestational diabetes**, but a patient with overt diabetes requires immediate pharmacologic intervention to prevent complications.
*Metformin*
- **Metformin** can be used in pregnancy but is primarily considered for **gestational diabetes** or as an alternative to insulin if the patient has milder hyperglycemia, or if insulin is poorly tolerated.
- Given the patient's significantly elevated fasting glucose and HbA1c, **insulin** is a more effective and immediate treatment to achieve glycemic control and reduce risks.
*Glyburide*
- **Glyburide** is an **oral sulfonylurea** that can cross the placenta, leading to potential fetal hyperinsulinemia and neonatal hypoglycemia.
- Its use in pregnancy is generally discouraged due to these risks, making **insulin** a safer and more appropriate choice.
Question 124: A 36-year-old G4P3 is admitted to the obstetrics floor at 35 weeks gestation with painless vaginal spotting for a week. She had 2 cesarean deliveries. An ultrasound examination at 22 weeks gestation showed a partial placenta previa, but she was told not to worry. Today, her vital signs are within normal limits, and a physical examination is unremarkable, except for some blood traces on the perineum. The fetal heart rate is 153/min. The uterine fundus is at the xiphoid process and uterine contractions are absent. Palpation identifies a longitudinal lie. Transvaginal ultrasound shows an anterior placement of the placenta with a placental edge-to-internal os distance of 1.5 cm and a loss of the retroplacental space. Which of the following statements best describes the principle of management for this patient?
A. Cesarean hysterectomy should be considered for the management of this patient
B. She can be managed with an unscheduled vaginal delivery with a switch to cesarean delivery if needed
C. Any decision regarding the mode of delivery in this patient should be taken after an amniocentesis to determine the fetal lung maturity
D. This patient without a significant prepartum bleeding is unlikely to have an intra- or postpartum bleeding
E. With such placental position, she should be managed with a scheduled cesarean in the lower uterine segment at 37 weeks’ pregnancy (Correct Answer)
Explanation: ***With such placental position, she should be managed with a scheduled cesarean in the lower uterine segment at 37 weeks’ pregnancy***
- This patient presents with signs highly suggestive of **placenta accreta spectrum (PAS)**, including a history of multiple **cesarean deliveries**, current **partial placenta previa** (placental edge 1.5 cm from internal os), and a **loss of retroplacental space** on ultrasound, all of which increase the risk of massive hemorrhage. A **scheduled cesarean section at 37 weeks** is the standard management for placenta previa and suspected accreta without significant bleeding, as it allows for proper preparation, a multidisciplinary team, and optimized outcomes.
- Delaying delivery until 37 weeks, if the patient remains stable without significant bleeding, helps to ensure **fetal lung maturity** while minimizing maternal risks associated with prolonged pregnancy in the presence of PAS disorders.
*Cesarean hysterectomy should be considered for the management of this patient*
- While **cesarean hysterectomy** might ultimately be necessary in cases of confirmed placenta accreta spectrum with significant invasion, it is typically a **contingency plan** for managing severe hemorrhage or unmanageable placental adherence during a planned cesarean delivery, not the *initial primary management* decision without more extensive bleeding or definitive diagnosis pre-delivery.
- Elective cesarean hysterectomy is associated with **increased morbidity** and is usually reserved for cases where conservative management of the placenta is deemed unsafe or unsuccessful during surgery.
*She can be managed with an unscheduled vaginal delivery with a switch to cesarean delivery if needed*
- The presence of even a **partial placenta previa** and suspected **placenta accreta spectrum** makes vaginal delivery unsafe due to a high risk of **massive hemorrhage** when the cervix dilates or the placenta detaches.
- An unscheduled attempt at vaginal delivery could lead to an **emergency situation**, compromising both maternal and fetal well-being, and is contraindicated with this placental position.
*Any decision regarding the mode of delivery in this patient should be taken after an amniocentesis to determine the fetal lung maturity*
- While fetal lung maturity is a concern for preterm deliveries, the primary concern in this patient is the **maternal risk of hemorrhage** associated with placenta previa and suspected accreta, which dictates the timing and mode of delivery.
- Given the high suspicion for **placenta accreta spectrum**, delaying delivery for amniocentesis adds unnecessary risk without significantly altering the mode of delivery, which will almost certainly be a **cesarean section** regardless of lung maturity results.
*This patient without a significant prepartum bleeding is unlikely to have an intra- or postpartum bleeding*
- This statement is incorrect. The classic presentation of **placenta accreta spectrum** often involves **painless vaginal bleeding** as described, and the absence of *significant* prepartum bleeding does not negate the high risk of **severe intrapartum or postpartum hemorrhage** due to the abnormally adherent placenta.
- The risk of hemorrhage in PAS is primarily associated with the **failure of placental separation** during or after delivery, not necessarily with pre-delivery bleeding patterns.
Question 125: A 22-year-old nulligravid woman comes to the physician for evaluation of irregular periods. Menarche was at the age of 12 years. Her menses have always occurred at variable intervals, and she has spotting between her periods. Her last menstrual period was 6 months ago. She has diabetes mellitus type 2 and depression. She is not sexually active. She drinks 3 alcoholic drinks on weekends and does not smoke. She takes metformin and sertraline. She appears well. Her temperature is 37°C (98.6°F), pulse is 82/min, respirations are 15/min, and blood pressure is 118/75 mm Hg. BMI is 31.5 kg/m2. Physical exam shows severe cystic acne on her face and back. There are dark, velvet-like patches on the armpits and neck. Pelvic examination is normal. A urine pregnancy test is negative. Which of the following would help determine the cause of this patient's menstrual irregularities?
A. Measurement of thyroid-stimulating hormone
B. Administration of estrogen
C. Measurement of follicle-stimulating hormone
D. Measurement of prolactin levels
E. Progesterone withdrawal test (Correct Answer)
Explanation: ***Progesterone withdrawal test***
- A **progesterone withdrawal test** can help determine if the patient has sufficient endogenous estrogen to build up the endometrium. If she bleeds after progesterone, it suggests **anovulation** with adequate estrogen.
- This test is crucial for differentiating causes of **amenorrhea** or **oligomenorrhea** by assessing the functional status of the hypothalamic-pituitary-ovarian axis and endometrial response.
*Measurement of thyroid-stimulating hormone*
- While **thyroid dysfunction** can cause menstrual irregularities, the patient's other symptoms (acne, hirsutism, obesity, acanthosis nigricans) point more strongly towards a different endocrine disorder.
- Her vital signs and general appearance (well-appearing) do not strongly suggest significant **hypo- or hyperthyroidism**.
*Administration of estrogen*
- Administering estrogen without first assessing the patient's endogenous estrogen levels or response to progesterone would not directly help determine the underlying cause of her *current* menstrual irregularities.
- Estrogen is typically used in combination with progesterone to induce withdrawal bleeding in cases of **hypoestrogenic prolonged amenorrhea**, which is not yet confirmed here.
*Measurement of follicle-stimulating hormone*
- **FSH levels** are primarily used to evaluate **ovarian reserve** or to diagnose **primary ovarian insufficiency** (high FSH) or **hypothalamic amenorrhea** (low or normal FSH).
- Given the patient's presentation with **acne, obesity, and insulin resistance (diabetes mellitus type 2)**, the primary concern is more likely an anovulatory disorder like **PCOS**, where FSH levels are often normal.
*Measurement of prolactin levels*
- Elevated **prolactin levels** can cause menstrual irregularities and amenorrhea by inhibiting GnRH pulsatility and subsequent FSH/LH release.
- While hyperprolactinemia should be considered in cases of unexplained amenorrhea, the patient's prominent symptoms of **cystic acne**, **acanthosis nigricans**, and **obesity** point more strongly towards hyperandrogenism and insulin resistance.
Question 126: A 32-year-old G2P0A1 woman presents at 36 weeks of gestation for the first time during her pregnancy. The patient has no complaints, currently. However, her past medical history reveals seizure disorder, which is under control with valproic acid and lithium. She has not seen her neurologist during the past 2 years, in the absence of any complaints. She also reports a previous history of elective abortion. The physical examination is insignificant. Her blood pressure is 130/75 mm Hg and pulse is 80/min. The patient is scheduled to undergo regular laboratory tests and abdominal ultrasound. Given her past medical history, which of the following conditions is her fetus most likely going to develop?
A. Neural tube defects (NTDs) (Correct Answer)
B. Intrauterine growth restriction
C. Iron deficiency anemia
D. Trisomy 21
E. Limb anomalies
Explanation: **Neural tube defects (NTDs)**
* The use of **valproic acid** during pregnancy is significantly associated with an increased risk of **neural tube defects (NTDs)**, such as spina bifida and anencephaly, in the fetus.
* Valproic acid interferes with **folate metabolism**, which is crucial for proper neural tube closure during early fetal development.
*Intrauterine growth restriction*
* While some medications and maternal conditions can cause **intrauterine growth restriction (IUGR)**, valproic acid and lithium are **not primary causes** of IUGR.
* Other factors, such as **placental insufficiency**, severe maternal hypertension, or infections, are more commonly associated with IUGR.
*Iron deficiency anemia*
* **Iron deficiency anemia** is a common maternal condition in pregnancy, but it is **not a direct fetal outcome** of maternal valproic acid or lithium use.
* Fetal anemia might occur due to other causes like **Rh incompatibility** or parvovirus infection.
*Trisomy 21*
* **Trisomy 21 (Down syndrome)** is a **chromosomal anomaly** caused by the presence of an extra copy of chromosome 21.
* It is not related to maternal medication use like valproic acid or lithium; its incidence is primarily correlated with **advanced maternal age**.
*Limb anomalies*
* Although several teratogenic medications can cause **limb anomalies**, **valproic acid** is more strongly linked to **neural tube defects** and certain **cardiac anomalies**.
* **Thalidomide**, for example, is notoriously associated with severe limb malformations.
Question 127: A 23-year-old primigravida presents to her physician’s office at 12 weeks gestation complaining of increased sweating and palpitations for the last week. She does not have edema or dyspnea, and had no pre-existing illnesses. The patient says that the symptoms started a few days after several episodes of vomiting. She managed the vomiting at home and yesterday the vomiting stopped, but the symptoms she presents with are persistent. The pre-pregnancy weight was 54 kg (119 lb). The current weight is 55 kg (121 lb). The vital signs are as follows: blood pressure 130/85 mm Hg, heart rate 113/min, respiratory rate 15/min, and temperature 37.0℃ (98.6℉). The physical examination is significant for diaphoresis, an irregular heartbeat, and a fine resting tremor of the hands. The neck is not enlarged and the thyroid gland is not palpable. The ECG shows sinus tachyarrhythmia. The thyroid panel is as follows:
Thyroid stimulating hormone (TSH) < 0.1 mU/L
Total T4 178 nmol/L
Free T4 31 pmol/L
Which of the following is indicated?
A. Recommend iodine radioablation
B. Schedule a subtotal thyroidectomy
C. Prescribe methimazole
D. Manage with propylthiouracil
E. Ensure proper hydration and prescribe a beta-blocker (Correct Answer)
Explanation: ***Ensure proper hydration and prescribe a beta-blocker***
- The patient's symptoms (sweating, palpitations, irregular heartbeat, tremor, tachycardia, low TSH, high T4) are consistent with **hyperthyroidism**. However, her symptoms started shortly after persistent vomiting (hyperemesis gravidarum), and the thyroid is not enlarged, suggesting **gestational transient thyrotoxicosis (GTT)** rather than Graves' disease. GTT is typically mild and self-limiting, often resolving by mid-gestation.
- Since the patient is pregnant, definitive treatments like **radioiodine ablation** or **thyroidectomy** are contraindicated. Antithyroid medications (methimazole, PTU) are also generally avoided in GTT unless symptoms are severe, due to potential side effects for both mother and fetus. The primary management for mild to moderate GTT involves supportive care, such as ensuring proper hydration and using **beta-blockers** (e.g., propranolol) to alleviate adrenergic symptoms like palpitations and tremors.
*Recommend iodine radioablation*
- **Radioactive iodine (RAI) therapy** for hyperthyroidism is absolutely **contraindicated in pregnancy** because radioactive iodine crosses the placenta and can destroy the fetal thyroid gland, leading to congenital hypothyroidism.
- This treatment is primarily used for definitive treatment of hyperthyroidism in non-pregnant patients, particularly for **Graves' disease** or toxic nodular goiter.
*Schedule a subtotal thyroidectomy*
- **Thyroidectomy** at 12 weeks gestation carries significant risks to both the mother (surgical complications) and the fetus (miscarriage, preterm labor). It is considered only in very rare cases of severe, uncontrolled hyperthyroidism refractory to medical management, typically in the second trimester.
- Given the suspicion of **gestational transient thyrotoxicosis (GTT)**, a self-limiting condition, surgical intervention is highly inappropriate.
*Prescribe methimazole*
- **Methimazole** is an antithyroid drug used to reduce thyroid hormone synthesis. While effective for hyperthyroidism, it is generally **avoided in the first trimester of pregnancy** due to its association with rare but severe fetal abnormalities, such as aplasia cutis.
- For gestational transient thyrotoxicosis, antithyroid drugs are typically not necessary because the condition is usually mild and self-limiting.
*Manage with propylthiouracil*
- **Propylthiouracil (PTU)** is another antithyroid drug that blocks thyroid hormone synthesis. It is typically **preferred over methimazole during the first trimester of pregnancy** when antithyroid medication is absolutely necessary, as it has a lower risk of teratogenicity during this period.
- However, PTU itself carries risks, including rare but severe **hepatotoxicity**, and is generally reserved for cases of severe hyperthyroidism where the benefits outweigh the risks. In mild to moderate gestational transient thyrotoxicosis, medications like PTU are usually not required.
Question 128: A 27-year-old pregnant woman presents to an obstetrician at 35 weeks gestation reporting that she noted the presence of a mucus plug in her vaginal discharge this morning. The obstetrician performs an examination and confirms that she is in labor. She was diagnosed with HIV infection 1 year ago. Her current antiretroviral therapy includes abacavir, lamivudine, and nevirapine. Her last HIV RNA level was 2,000 copies/mL 3 weeks ago. Which of the following anti-retroviral drugs should be administered intravenously to the woman during labor?
A. Enfuvirtide
B. Nevirapine
C. Abacavir
D. Rilpivirine
E. Zidovudine (Correct Answer)
Explanation: ***Zidovudine***
- Intravenous **zidovudine** is recommended during labor for HIV-positive pregnant women, especially when the viral load is **>1000 copies/mL**, to reduce the risk of **mother-to-child transmission (MTCT)**.
- This intervention significantly lowers the viral load in the maternal blood and reduces fetal exposure to the virus during delivery.
*Enfuvirtide*
- **Enfuvirtide** is a **fusion inhibitor** administered subcutaneously, not intravenously, and is reserved for treatment-experienced patients with multi-drug resistant HIV.
- It is not a standard recommendation for intrapartum prophylaxis against MTCT.
*Nevirapine*
- **Nevirapine** is an **NNRTI** that is typically given orally, and while it has been used for MTCT prophylaxis, intravenous administration is not standard for intrapartum use.
- The woman is already on oral nevirapine as part of her ART regimen.
*Abacavir*
- **Abacavir** is an **NRTI** given orally and is part of the patient's current ART regimen.
- It is not administered intravenously for intrapartum MTCT prophylaxis.
*Rilpivirine*
- **Rilpivirine** is an **NNRTI** that is taken orally and is not indicated for intravenous administration during labor to prevent MTCT.
- Its use is limited by potential drug interactions and efficacy in patients with high viral loads.
Question 129: A 36-year-old woman, gravida 3, para 2, at 37 weeks' gestation comes to the emergency department because of sparse vaginal bleeding for 3 hours. She also noticed the bleeding 3 days ago. She has had no prenatal care. Both of her previous children were delivered by lower segment transverse cesarean section. Her temperature is 37.1°C (98.8°F), pulse is 90/min, respirations are 16/min, and blood pressure is 110/80 mm Hg. The abdomen is nontender, and no contractions are felt. Examination shows that the fetus is in a vertex presentation. The fetal heart rate is 160/min and shows no abnormalities. Which of the following is the most appropriate next step in management?
A. Perform cesarean delivery
B. Perform transvaginal sonography (Correct Answer)
C. Perform Kleihauer-Betke test
D. Perform pelvic examination
E. Conduct contraction stress test
Explanation: ***Perform transvaginal sonography***
- The history of **previous cesarean sections** and **painless vaginal bleeding** raises suspicion for **placenta previa**.
- **Transvaginal sonography** is the gold standard for diagnosing placenta previa, as it accurately visualizes the relationship between the placenta and the cervical os without increasing bleeding risk.
*Perform cesarean delivery*
- While a cesarean delivery may eventually be necessary if **placenta previa** is confirmed, it is premature to proceed without a definitive diagnosis.
- An immediate cesarean delivery is indicated only in cases of **heavy, uncontrolled bleeding** or fetal distress, neither of which is present here.
*Perform Kleihauer-Betke test*
- The **Kleihauer-Betke test** measures the amount of fetal hemoglobin transferred into the maternal bloodstream for quantifying **fetomaternal hemorrhage**, which is typically performed after a potential placental abruption or trauma.
- This test is not primarily used for diagnosing the **cause of vaginal bleeding** in this context and would not identify placenta previa.
*Perform pelvic examination*
- A **digital pelvic examination** is **contraindicated** in cases of suspected placenta previa due to the risk of exacerbating bleeding and potentially causing **massive hemorrhage**.
- Even a speculum examination should generally be deferred until a sonogram has ruled out placenta previa to avoid disturbing the placenta.
*Conduct contraction stress test*
- A **contraction stress test** assesses **fetal well-being** in response to uterine contractions and is used to evaluate uteroplacental insufficiency.
- It does not help in diagnosing the cause of **vaginal bleeding** and is not the appropriate first step in a patient with suspected placenta previa.
Question 130: A 16-year-old girl is brought to the physician because she has not yet had her 1st period. She was born at 39 weeks gestation via spontaneous vaginal delivery. She is up to date on all vaccines and meeting all developmental milestones. She has no history of a serious illness and takes no medications. Physical examination shows underdeveloped breasts with scant pubic and axillary hair. Speculum examination shows a short vagina and no cervix. The remainder of the physical examination shows no abnormalities. Pelvic ultrasound shows no uterus. Which of the following is the most likely karyotype in this patient?
A. 47,XXY
B. 45,X
C. 46,XY (Correct Answer)
D. 46,XX/46,XY
E. 46,XX
Explanation: ***46,XY***
- This karyotype describes an individual who is genetically male but presents phenotypically as female, often seen in **androgen insensitivity syndrome (AIS)**.
- The patient's underdeveloped breasts, scant pubic/axillary hair, short vagina with no cervix, and absent uterus (on ultrasound) are classic signs of AIS, where **testosterone is produced but tissues are unresponsive** due to receptor defects, leading to female external genitalia development and lack of Müllerian structures.
*47,XXY*
- This karyotype is associated with **Klinefelter syndrome**, which affects males and typically presents with tall stature, small testes, gynecomastia, and infertility.
- It does not explain the absence of a uterus or Mullerian structures, nor the specific presentation of underdeveloped secondary sexual characteristics in a phenotypic female.
*45,X*
- This karyotype describes **Turner syndrome**, which presents with primary amenorrhea, short stature, webbed neck, and **streak gonads** (absent or non-functional ovaries).
- While it causes primary amenorrhea and underdeveloped secondary sexual characteristics, Turner syndrome patients typically have a **uterus** (though small) and do not have an absent cervix or a short vagina in the way described.
*46,XX/46,XY*
- This represents **gonadal mosaicism**, where an individual has cell lines with both male and female karyotypes.
- The clinical presentation can be highly variable, ranging from ambiguous genitalia to female or male phenotypes, but it does not specifically account for the precise combination of primary amenorrhea, absent uterus, and underdeveloped secondary sexual characteristics as seen in AIS.
*46,XX*
- This is the normal female karyotype. While it can be associated with primary amenorrhea in conditions such as **Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome** (agenesis of the uterus and upper vagina), it would be accompanied by normal breast and pubic/axillary hair development due to functional ovaries.
- The patient's underdeveloped breasts and scant pubic/axillary hair suggest a problem with androgen action, not simply Müllerian agenesis in an otherwise hormonally normal female.
