Placental development and function — MCQs

A 26-year-old woman comes to the emergency department because of a 3-day history of nausea and vomiting. Her last menstrual period was 9 weeks ago. A urine pregnancy test is positive. Ultrasonography shows an intrauterine pregnancy consistent in size with a 7-week gestation. The hormone that was measured in this patient's urine to detect the pregnancy is also directly responsible for which of the following processes?

A 30-year-old woman, gravida 2, para 1, at 12 weeks' gestation comes to the physician for a prenatal visit. She feels well. Pregnancy and vaginal delivery of her first child were uncomplicated. Five years ago, she was diagnosed with hypertension but reports that she has been noncompliant with her hypertension regimen. The patient does not smoke or drink alcohol. She does not use illicit drugs. Medications include methyldopa, folic acid, and a multivitamin. Her temperature is 37°C (98.6°F), pulse is 80/min, and blood pressure is 145/90 mm Hg. Physical examination shows no abnormalities. Laboratory studies, including serum glucose level, and thyroid-stimulating hormone concentration, are within normal limits. The patient is at increased risk of developing which of the following complications?

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 31-year-old G3P2 who is at 24 weeks gestation presents for a regular check-up. She has no complaints, no concurrent diseases, and her previous pregnancies were vaginal deliveries with birth weights of 3100 g and 4180 g. The patient weighs 78 kg (172 lb) and is 164 cm (5 ft 5 in) in height. She has gained 10 kg (22 lb) during the current pregnancy. Her vital signs and physical examination are normal. The plasma glucose level is 190 mg/dL after a 75-g oral glucose load. Which of the listed factors contributes to the pathogenesis of the patient’s condition?

A 3175-g (7-lb) male newborn is delivered at 39 weeks' gestation to a 29-year-old primigravid woman following a spontaneous vaginal delivery. Apgar scores are 8 and 9 at 1 and 5 minutes, respectively. Cardiac examination in the delivery room shows a continuous machine-like murmur. An echocardiogram shows a structure with blood flow between the pulmonary artery and the aorta. This structure is most likely a derivate of which of the following?

Thirty minutes after normal vaginal delivery of twins, a 35-year-old woman, gravida 5, para 4, has heavy vaginal bleeding with clots. Physical examination shows a soft, enlarged, and boggy uterus. Despite bimanual uterine massage, administration of uterotonic drugs, and placement of an intrauterine balloon for tamponade, the bleeding continues. A hysterectomy is performed. Vessels running through which of the following structures must be ligated during the surgery to achieve hemostasis?

A 26-year-old woman comes to the physician because she has not had a menstrual period for 5 weeks. Menarche was at the age of 14 years and menses occurred at regular 30-day intervals. She reports having unprotected sexual intercourse 3 weeks ago. A urine pregnancy test is positive. Which of the following best describes the stage of development of the embryo at this time?

A 32-year-old woman, gravida 2, para 1, at 20 weeks' gestation comes to the physician for a prenatal visit. She feels well. Her first pregnancy was uncomplicated and the child was delivered vaginally. Medications include folic acid and an iron supplement. Her temperature is 37°C (98.6°F), pulse is 98/min, respirations are 18/min, and blood pressure is 108/76 mm Hg. Abdominal examination shows a uterus that is consistent with a 20-week gestation. The second-trimester scan shows no abnormalities. The patient intends to travel next month to Mozambique to visit her grandmother. Which of the following drugs is most suitable for pre-exposure prophylaxis against malaria?

A 29-year-old woman is brought to the emergency room for seizure-like activity. Her husband reports that they were in bed sleeping when his wife began complaining of “hot flashes.” Several minutes later, her right arm began to twitch, and she did not respond to his calls. The whole episode lasted for about 5 minutes. She denies any prior similar episodes, tongue biting, loss of bowel or urinary control, new medications, or recent illness. She reports a family history of epilepsy and is concerned that she might have the same condition. Urine pregnancy test is positive. If this patient is prescribed phenytoin, during which of the following weeks is the fetus most sensitive to its side effects?

A 30-year-old primigravid woman at 16 weeks' gestation comes to the emergency department because of vaginal bleeding. She has had spotting for the last 2 days. She has had standard prenatal care. A viable uterine pregnancy was confirmed on ultrasonography during a prenatal care visit 2 weeks ago. She reports recurrent episodes of pain in her right wrist and both knees. Until pregnancy, she smoked one pack of cigarettes daily for the past 11 years. Pelvic examination shows an open cervical os and blood within the vaginal vault. Laboratory studies show: Hemoglobin 9.6 g/dL Leukocyte count 8,200/mm3 Platelet count 140,000/mm3 Prothrombin time 14 seconds Partial thromboplastin time 46 seconds Serum Na+ 136 mEq/L K+ 4.1 mEq/L Cl- 101 mEq/L Urea nitrogen 12 mg/dL Creatinine 1.3 mg/dL AST 20 U/L ALT 15 U/L Ultrasonography shows an intrauterine pregnancy and no fetal cardiac activity. Which of the following is the most likely explanation for this patient's examination findings?