OB Mock Exam

Which structure secretes progesterone to maintain early pregnancy?

• Placenta

• Corpus luteum

• Chorion

• Amnion

Answer explanation

The corpus luteum is the structure that secretes progesterone, which is crucial for maintaining the uterine lining and supporting early pregnancy until the placenta takes over hormone production.

Which is a presumptive sign of pregnancy?

• Positive pregnancy test

• Ultrasound showing fetal sac

• Amenorrhea

• Auscultation of fetal heart tones

Answer explanation

Amenorrhea, or the absence of menstruation, is a presumptive sign of pregnancy. It indicates a possible pregnancy, while the other options are more definitive signs.

Which cardiovascular change occurs during pregnancy?

• Cardiac output decreases

• Blood volume decreases

• Cardiac output increases by 30-50%

• Systemic vascular resistance increases

Answer explanation

During pregnancy, cardiac output increases by 30-50% to meet the increased metabolic demands of the mother and fetus. This is essential for adequate blood flow and oxygen delivery.

Which discomfort is related to progesterone relaxing smooth muscle?

• Heartburn

• Leg cramps

• Supine hypotension

• Round ligament pain

Answer explanation

Heartburn is related to progesterone's effect of relaxing smooth muscle, which can lead to decreased lower esophageal sphincter tone, allowing stomach acid to reflux into the esophagus, causing discomfort.

When do prenatal visits typically become weekly?

• 20 weeks

• 28 weeks

• 36 weeks

• 40 weeks

Answer explanation

Prenatal visits typically become weekly at 36 weeks of pregnancy. This is to closely monitor the health of both the mother and the baby as the due date approaches.

Which test confirms fetal genetic disorders?

• Quad screen

• NIPT

• Chorionic villus sampling

• Cell-free DNA

Answer explanation

Chorionic villus sampling (CVS) is a diagnostic test that involves taking a sample of placental tissue to test for genetic disorders in the fetus. Unlike screening tests, CVS provides definitive results for specific genetic conditions.

Which vitamin prevents neural tube defects?

• Folic acid

• Iron

• Calcium

• Vitamin D

Answer explanation

Folic acid is crucial in preventing neural tube defects during early pregnancy. It helps in the proper development of the neural tube, which forms the baby's brain and spinal cord.

What is the purpose of Rhogam administration?

• Prevent gestational diabetes

• Prevent hemolytic disease in fetus

• Treat anemia

• Prevent neural tube defects

Answer explanation

Rhogam is administered to prevent hemolytic disease in the fetus, particularly in Rh-negative mothers. It works by preventing the mother's immune system from producing antibodies against Rh-positive blood cells from the fetus.

Which pelvic shape is most favorable for vaginal delivery?

• Android

• Platypelloid

• Gynecoid

• Anthropoid

Answer explanation

The gynecoid pelvic shape is most favorable for vaginal delivery due to its rounded shape and wider dimensions, allowing for easier passage of the baby during birth compared to other pelvic types.

Which hormone triggers uterine contractions?

• Progesterone

• Estrogen

• Oxytocin

• Prolactin

Answer explanation

Oxytocin is the hormone responsible for triggering uterine contractions during labor. It stimulates the smooth muscles of the uterus, facilitating childbirth, while progesterone and estrogen play different roles in pregnancy.