MCQ Obstetrics Answer 27

The correct answer is E.

The Group B Streptococcus (GBS) is a bacterium that is a part of the normal bacterial colonization of many women. During pregnancy, as many as 20-40% of women will be colonized with GBS. Most babies born to colonized mothers will not develop infection with GBS. However, approximately 1 to 4 % of neonates will develop infection.

The likelihood of infection is increased if the mother has preterm labor and delivery (< 37 weeks), prolonged rupture of the membranes (>18 hours), or intrapartum temperature greater than 38.0 C (100.4 F). Two primary methods are used to determine which women will receive antibiotics during labor. The first method is based upon risk factors.

The five risk factors are:
1. History of a GBS-affected neonate.
2. Urine culture with GBS.
3. Preterm labor (<37 weeks).
4. Membranes ruptured for greater than eighteen hours in labor.
5. Temperature greater than 38.0 C (100.4 F) in labor.

A woman with any one of these five risk factors should receive antibiotics in labor. The second method is based on screening, with pregnant women being screened for GBS at 35 to 37 weeks with a culture of the vagina, perineum, and anus. Women should be screened only if they do not have a history of a GBS-affected neonate or GBS bacteriuria. This patient has GBS bacteriuria; therefore, she did not undergo screening. She should be treated with penicillin during labor and delivery.

Betamethasone (choice A) is a corticosteroid that is given to women to accelerate fetal maturity to help prevent neonatal respiratory distress syndrome and other sequelae of prematurity. This patient is at 38 weeks' gestation and, therefore, does not require betamethasone.

Folic acid (choice B) is a supplement that women should take preconceptionally and during pregnancy (not during labor and delivery) to help prevent neural tube defects.

Magnesium sulfate (choice C) is used in obstetrics to prevent preterm labor and for seizure prophylaxis. This patient does not have preterm labor and does not have preeclampsia.

Oxytocin (choice D) is given to women to induce or to augment labor. This patient, however, appears not to need oxytocin as she is contracting every 5 minutes and progressing in labor.

Category: Obstetrics MCQs