A 23-year-old woman, gravida 2 para 1, at 30 weeks gestation comes to the emergency department due to a sudden gush of clear vaginal fluid. The patient continues to have leakage of clear fluid but no abdominal pain or vaginal bleeding. Fetal movement has been normal. The patient had intermittent vaginal bleeding during the first trimester but no other complications during this pregnancy. Her prior pregnancy ended in a term vaginal delivery. Temperature is 37.2 C (99 F), blood pressure is 110/70 mm Hg, and pulse is 82/min. The uterine fundus is nontender. Sterile speculum examination shows a closed cervix and vaginal pooling of nitrazine-positive, clear fluid. Ultrasound reveals a fetus in breech presentation and decreased amniotic fluid. Fetal heart rate tracing has a baseline of 130/min, moderate variability, and no decelerations. Tocometry shows no contractions. Which of the following is the best next step in management of this patient?
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This patient at <37 weeks gestation with vaginal pooling of nitrazine-positive fluid and a closed cervix (ie, prior to labor onset) has preterm prelabor rupture of membranes (PPROM). Risk factors are similar to those for preterm delivery (eg, multiple gestation, prior preterm delivery) but also include a history of prior PPROM, genital tract infection (eg, bacterial vaginosis), and antepartum bleeding, as in this patient. Management is dependent on gestational age and fetal/maternal status because the risks for fetal prematurity are balanced against maternal complications (eg, intraamniotic infection, abruptio placentae).
Patients with PPROM at <34 weeks gestation are at high risk for prematurity-related fetal morbidity and mortality; therefore, expectant management is aimed at promoting in utero fetal development and consists of the following:
Prophylactic latency antibiotics: PPROM is commonly due to a subclinical intraamniotic infection, and latency antibiotics prevent the infection from becoming fulminant, thereby increasing the time interval between membrane rupture and delivery (ie, prolonged latency).
Antenatal corticosteroids (eg, betamethasone): These are administered to promote fetal lung maturation (eg, pneumocyte development, surfactant release), thereby reducing neonatal morbidity and mortality.
Delivery is indicated if there are signs of intraamniotic infection (eg, fetal tachycardia, uterine tenderness) or deteriorating fetal/maternal status or if the pregnancy has reached 34 weeks gestation (Choices B and E).
(Choices A and F) Cerclage is used in patients with a history of cervical insufficiency (eg, painless cervical dilation), and progesterone therapy (eg, intramuscular, vaginal) is offered to patients with a prior preterm delivery. These interventions are intended to prevent PPROM and preterm delivery from recurring. Neither is used in patients after PPROM has occurred.
(Choice D) External cephalic version (ECV) is typically performed at ≥36 weeks gestation to manually correct fetal malpresentation (eg, breech). Ruptured membranes, decreased amniotic fluid, and fetal prematurity are all relative contraindications to ECV due to lower success rates and higher risks for fetal injury.
Educational objective:
Patients who have uncomplicated preterm prelabor rupture of membranes at <34 weeks gestation are managed expectantly with antibiotics and corticosteroids to promote in utero fetal development. Delivery is indicated if there are signs of intraamniotic infection or deteriorating fetal/maternal status or if the pregnancy has reached 34 weeks gestation.