Impact of the ACOG guideline regarding low-dose aspirin for prevention of superimposed preeclampsia in women with chronic hypertension.

BACKGROUND: Patients with chronic hypertension are at increased risk for superimposed preeclampsia. The 2016 American College of Obstetricians and Gynecologists guideline recommended initiating 81 mg of daily aspirin for all pregnant women with chronic hypertension to prevent superimposed preeclampsia. OBJECTIVE: (1) To evaluate the rates of implementation of the 2016 American College of Obstetricians and Gynecologists guideline over time; and (2) to evaluate the effectiveness of aspirin for the prevention of superimposed preeclampsia and other adverse maternal and neonatal outcomes in women with chronic hypertension before and after this guideline. STUDY DESIGN: This is a retrospective study of women with chronic hypertension who delivered at Thomas Jefferson University Hospital from January 2014 through June 2018. This cohort of women with chronic hypertension was divided into 2 groups, before and after the American College of Obstetricians and Gynecologists recommendation published in September 2016. Daily 81 mg of aspirin was initiated between 12 and 16 weeks. We excluded multiple gestations and incomplete records. The primary outcome was incidence of superimposed preeclampsia, and secondary outcomes were incidence of superimposed preeclampsia with or without severe features, small for gestational age, and preterm birth <37 weeks. Subgroup analysis based on risk stratification was evaluated in women with chronic hypertension requiring antihypertensive medication, history of preeclampsia, and pregestational diabetes. RESULTS: We identified 457 pregnant women with chronic hypertension, 203 in the post-American College of Obstetricians and Gynecologists group and 254 in the pre-American College of Obstetricians and Gynecologists group. Aspirin 81 mg was offered to 142 (70%) in the post-American College of Obstetricians and Gynecologists group and 18 (7.0%) in the pre-American College of Obstetricians and Gynecologists group. Maternal demographics were not significantly different. The overall incidence of superimposed preeclampsia was not significantly different: 87 (34.3%) vs 72 (35.5%), P=.79, in the pre- and post-American College of Obstetricians and Gynecologists guideline groups, respectively. Superimposed preeclampsia with severe features significantly increased: 32 (12.6%) vs 9 (4.4%), P<.01, whereas superimposed preeclampsia without severe features significantly decreased: 55 (21.7%) vs 63 (31.0%), P=.03. There were no significant differences in small for gestational age neonates or preterm birth <37 weeks incidences between groups. There were no significant differences in the subgroup analysis based on the severity of chronic hypertension requiring antihypertensive medication, history of preeclampsia, or pregestational diabetes. CONCLUSION: After the adoption of the American College of Obstetricians and Gynecologists guidelines in 70% of the cohort, superimposed preeclampsia, small for gestational age, and preterm birth were not significantly decreased after implementation of aspirin 81 mg initiated between 12 and 16 weeks of gestation.

Azithromycin vs erythromycin for the management of preterm premature rupture of membranes.

BACKGROUND: Preterm premature rupture of membranes complicates 2-3% of pregnancies. Many institutions have advocated for the use of azithromycin instead of erythromycin. This is secondary to national shortages of erythromycin, ease of administration, better side effect profile, and decreased cost of azithromycin as compared with erythromycin. OBJECTIVE: The objective of the study was to evaluate whether there are differences in the latency from preterm premature rupture of membranes to delivery in patients treated with different dosing regimens of azithromycin vs erythromycin. STUDY DESIGN: This is a multicenter, retrospective cohort of women with singleton pregnancies with confirmed rupture of membranes between 230 and 336 weeks from January 2010 to June 2015. Patients were excluded if there was a contraindication to expectant management of preterm premature rupture of membranes. Patients received 1 of 4 antibiotic regimens: (1) azithromycin 1000 mg per os once (azithromycin 1 day group); (2) azithromycin 500 mg per os once, followed by azithromycin 250 mg per os daily for 4 days (azithromycin 5 day group); (3) azithromycin 500 mg intravenously for 2 days, followed by azithromycin 500 mg per os daily for 5 days (azithromycin 7 day group); or (4) erythromycin intravenously for 2 days followed by erythromycin per os for 5 days (erythromycin group). The choice of macrolide was based on institutional policy and/or availability of antibiotics at the time of admission. In addition, all patients received ampicillin intravenously for 2 days followed by amoxicillin per os for 5 days. Primary outcome was latency from diagnosis of rupture of membranes to delivery. Secondary outcomes included clinical and histopathological chorioamnionitis and neonatal outcomes. RESULTS: Four hundred fifty-three patients who met inclusion criteria were identified. Seventy-eight patients received azithromycin for 1 day, 191 patients received azithromycin for 5 days, 52 patients received azithromycin for 7 days, and 132 patients received erythromycin. Women who received the 5 day regimen were younger and less likely to be non-African American, have hypertension, have sexually transmitted infection, or experienced substance abuse. There was no statistical difference in median latency time of azithromycin 1 day (4.9 days, 95% confidence interval, 3.3-6.4), azithromycin 5 days (5.0, 95% confidence interval, 3.9-6.1), or azithromycin 7 days (4.9 days, 95% confidence interval, 2.8-7.0) when compared with erythromycin (5.1 days, 95% confidence interval, 3.9-6.4) after adjusting for demographic variables (P = .99). Clinical chorioamnionitis was not different between groups in the adjusted model. Respiratory distress syndrome was increased in the azithromycin 5 day group vs azithromycin 1 day vs erythromycin (44% vs. 29% and 29%, P = .005, respectively). CONCLUSION: There was no difference in latency to delivery, incidence of chorioamnionitis, or neonatal outcomes when comparing different dosing regimens of the azithromycin with erythromycin, with the exception of respiratory distress syndrome being more common in the 5 day azithromycin group. Azithromycin could be considered as an alternative to erythromycin in the expectant management of preterm premature rupture of membranes if erythromycin is unavailable or contraindicated. There appears to be no additional benefit to an extended course of azithromycin beyond the single-day dosing, but final recommendations on dosing strategies should rely on clinical trials.