Vaginal progesterone vs intramuscular 17-hydroxyprogesterone caproate for prevention of recurrent preterm birth: a randomized controlled trial.

BACKGROUND: Preterm birth is the leading cause of neonatal morbidity and mortality, and previous preterm birth is one of the strongest risk factors for preterm birth. National and international obstetrical societies have different recommendations regarding progesterone formulation for the prevention of recurrent preterm birth. OBJECTIVE: This study aimed to determine whether vaginal progesterone is superior to 17-hydroxyprogesterone caproate in the prevention of recurrent preterm birth in patients with singleton pregnancies who had a previous spontaneous preterm birth. STUDY DESIGN: This was an open-label multicenter pragmatic randomized controlled trial at 5 US centers of patients with singleton pregnancies at <24 weeks of gestation who had a previous spontaneous preterm birth randomized 1:1 to either 200 mg vaginal progesterone suppository nightly or 250 mg intramuscular 17-hydroxyprogesterone caproate weekly from 16 to 36 weeks of gestation. Based on the estimated recurrent preterm birth rate of 36% with 17-hydroxyprogesterone caproate, 95 participants were needed in each arm to detect a 50% reduction in preterm birth rate with vaginal progesterone, with 80% power and 2-sided alpha of 0.05. The primary outcome was preterm birth at <37 weeks of gestation. Prespecified secondary outcomes included preterm birth at <34 and <28 weeks of gestation, mean gestational age at delivery, neonatal morbidity and mortality, and measures of adherence. Analysis was by intention to treat. The chi-square test and Student t test were used as appropriate. P<.05 was considered significant. RESULTS: Overall, 205 participants were randomized; 94 participants in the vaginal progesterone group and 94 participants in 17-hydroxyprogesterone caproate group were included. Although gestational age at enrollment was similar, those assigned to vaginal progesterone initiated therapy earlier (16.9±1.4 vs 17.8±2.5 weeks; P=.001). Overall continuation of assigned formulation until delivery was similar (73% vs 69%; P=.61). There was no significant difference in preterm birth at <37 (31% vs 38%; P=.28; relative risk, 0.81 [95% confidence interval, 0.54-1.20]), <34 (9.6% vs 14.9%; P=.26; relative risk, 0.64 [95% confidence interval, 0.29-1.41]), or <28 (1.1% vs 4.3%; P=.37; relative risk, 0.25 [95% confidence interval, 0.03-2.20]) weeks of gestation. Participants in the vaginal progesterone group had a later mean gestational age at delivery than participants in the 17-hydroxyprogesterone caproate group (37.36±2.72 vs 36.34±4.10 weeks; mean difference, 1.02 [95% confidence interval, 0.01-2.01]; P=.047). CONCLUSION: Vaginal progesterone did not reduce the risk of recurrent preterm birth by 50% compared with 17-OHPC; however, vaginal progesterone may lead to increased latency to delivery. This trial was underpowered to detect a smaller, but still clinically significant, difference in the efficacy of preterm birth prevention. Patient factors that impact adherence and ability to obtain medication in a timely fashion should be included in counseling on progesterone selection.

Placental Production of Eicosanoids and Sphingolipids in Women Who Developed Preeclampsia on Low-Dose Aspirin.

Low-dose aspirin, which selectively inhibits thromboxane synthesis, is now standard of care for the prevention of preeclampsia in at risk women, but some women still develop preeclampsia despite an aspirin regimen. To explore the "aspirin failures," we undertook a comprehensive evaluation of placental lipids to determine if abnormalities in non-aspirin sensitive lipids might help explain why some women on low-dose aspirin develop preeclampsia. We studied placentas from women with normal pregnancies and women with preeclampsia. Placental villous explants were cultured and media analyzed by mass spectrometry for aspirin-sensitive and non-aspirin-sensitive lipids. In women who developed severe preeclampsia and delivered preterm, there were significant elevations in non-aspirin-sensitive lipids with biologic actions that could cause preeclampsia. There were significant increases in 15- and 20-hydroxyeicosatetraenoic acids and sphingolipids: D-e-C18:0 ceramide, D-e-C18:0 sphingomyelin, D-e-sphingosine-1-phosphate, and D-e-sphinganine-1-phosphate. With regard to lipids sensitive to aspirin, there was no difference in placental production of thromboxane or prostacyclin, but prostaglandins were lower. There was no difference for isoprostanes, but surprisingly, anti-inflammatory omega 3 and 6 PUFAs were increased. In total, 10 of 30 eicosanoids and 5 of 42 sphingolipids were abnormal in women with severe early onset preeclampsia. Lipid changes in women with mild preeclampsia who delivered at term were of lesser magnitude with few significant differences. The placenta produces many aspirin-sensitive and non-aspirin-sensitive lipids. Abnormalities in eicosanoids and sphingolipids not sensitive to aspirin might explain why some aspirin-treated women develop preeclampsia.

A randomized open-label controlled trial of chlorhexidine-alcohol vs povidone-iodine for cesarean antisepsis: the CAPICA trial.

BACKGROUND: Identification of optimal surgical site antisepsis preparations may reduce cesarean-related surgical site infections. Two recently published investigations examined efficacy of chlorhexidine-alcohol and iodine-alcohol preparations. No previous randomized controlled trial has compared chlorhexidine-alcohol to povidone-iodine aqueous scrub and paint in reduction of cesarean-related surgical site infection. OBJECTIVE: The purpose of the study was to determine if chlorhexidine-alcohol would result in fewer surgical site infections than povidone-iodine when used as skin antisepsis preparation prior to cesarean delivery. STUDY DESIGN: This study was a single-center pragmatic randomized controlled trial at an urban tertiary care institution to compare chlorhexidine-alcohol 26-mL single-step applicator to povidone-iodine aqueous scrub and paint 236-mL wet skin tray as preoperative skin antiseptic preparation for women undergoing cesarean delivery. Patients were eligible for study participation if they could provide informed consent in English or Spanish, were ≥18 years of age, did not have clinical chorioamnionitis, were unlikely to be lost to follow-up, and had no sensitivities to chlorhexidine, betadine, or iodine. Treatment was assigned by computer-generated simple 1:1 randomization immediately before skin preparation. The primary outcome was surgical site infection occurring within 30 days of cesarean delivery including ≥1 of: superficial or deep surgical site infection, or endometritis, according to Centers for Disease Control and Prevention definitions. Analysis was by intent to treat. Categorical outcomes were compared using Fisher exact test. The Wilcoxon rank-sum test was performed for continuous outcomes. This trial was institutional review board approved and registered at ClinicalTrials.gov (NCT02202577). RESULTS: In all, 932 subjects (461 assigned to chlorhexidine-alcohol, 471 assigned to povidone-iodine) were randomized from February 2013 through May 2016. Rate of follow-up evaluation after 30 days was 99% (455) in the chlorhexidine-alcohol group and 97% (455) in the povidone-iodine group. Surgical site infection occurred in 29 (6.3%) of the chlorhexidine-alcohol group and 33 (7.0%) in the povidone-iodine group (P = .38). The rates of individual components of the primary outcome were as follows: superficial surgical site infection (4.6% v 5.5%; P = .55), deep surgical site infection (0.0% v 0.4%; P = .50), and endometritis (1.7% v 1.1%; P = .42) in chlorhexidine-alcohol vs povidone-iodine arms, respectively. All results were similar in per protocol analysis. CONCLUSION: Preoperative antiseptic skin preparation with chlorhexidine-alcohol 26-mL single-step applicator before cesarean did not result in less frequent surgical site infection when compared with povidone-iodine aqueous scrub and paint 236-mL wet skin preparation tray. Povidone-iodine should still be considered as acceptable for preoperative surgical site antisepsis for cesarean delivery.

Progesterone inhibits in vitro fetal membrane weakening.

OBJECTIVE: Inflammation/infection and abruption are leading causes of preterm premature rupture of the membranes. Recently, we identified granulocyte-macrophage colony-stimulating factor (GM-CSF) as a critical mediator of both tumor necrosis factor-α- (TNF; modeling inflammation) and thrombin-induced (modeling abruption) weakening of the fetal membranes. We found that (1) TNF and thrombin both induced GM-CSF in the choriodecidua, (2) blockade of GM-CSF action with neutralizing antibodies inhibited both TNF- and thrombin-induced fetal membrane weakening, and (3) GM-CSF alone induced fetal membrane weakening. GM-CSF is thus part of an overlap of the inflammation and abruption-induced fetal membrane weakening pathways. The effects of progesterone analogs on the pathways by which fetal membranes are weakened have not been investigated. We examined the effects of progesterone, medroxyprogesterone acetate (MPA) and 17α-hydroxyprogesterone (HP) on TNF- and thrombin-induced fetal membrane weakening. STUDY DESIGN: Full-thickness fetal membranes from uncomplicated term repeat cesarean deliveries were mounted in Transwell inserts in Minimum Essential Medium alpha and incubated at 37°C in 5% CO2. The choriodecidua side of the fetal membrane fragments were preincubated with progesterone, MPA, HP, or vehicle for 24 hours. Fetal membranes were then exposed to TNF, thrombin, or GM-CSF on the choriodecidua side for an additional 48 hours. The fetal membrane tissues were then strength tested, and medium from the choriodecidua and amnion compartments was assayed for GM-CSF content. RESULTS: TNF and thrombin both weakened fetal membranes and elevated media GM-CSF levels on the choriodecidua side of the fetal membrane. Pretreatment with progesterone, MPA, or HP inhibited both TNF- and thrombin-induced fetal membrane weakening and also inhibited the induced increase in GM-CSF. GM-CSF decreased fetal membrane rupture strength by 68%, which was inhibited by progestogen pretreatment with a potency order: progesterone

Genetic contributions to disparities in preterm birth.

Ethnic disparity in preterm delivery between African Americans and European Americans has existed for decades, and is likely the consequence of multiple factors, including socioeconomic status, environment, and genetics. This review summarizes existing information on genetic variation and its association with preterm birth in African Americans. Candidate gene-based association studies, in which investigators have evaluated particular genes selected primarily because of their potential roles in the process of normal and pathologic parturition, provide evidence that genetic contributions from both mother and fetus account for some of the disparity in preterm births. To date, most attention has been focused on genetic variation in pro- and anti-inflammatory cytokine genes and their respective receptors. These genes, particularly the pro-inflammatory cytokine genes and their receptors, are linked to matrix metabolism because these cytokines increase expression of matrix degrading metalloproteinases. However, the role that genetic variants that are different between populations play in preterm birth (e.g. the SERPINH1 - G56 SNP) cannot yet be quantified. Future studies based on genome wide association or admixture mapping may reveal other genes that contribute to disparity in prematurity.