J Nikki McKoy

Progestogens for Preterm Birth Prevention A Systematic Review and Meta-Analysis

OBJECTIVE: We systematically reviewed the effectiveness of progestogens for prevention of preterm birth among women with prior spontaneous preterm birth, multiple gestations, preterm labor, short cervix, or other indications. DATA SOURCES: We searched MEDLINE and EMBASE databases for English language articles published from January 1966 to October 2011. METHODS OF STUDY SELECTION: We excluded publications that were not randomized controlled trials or had fewer than 20 participants, identifying 34 publications, of which 19 contained data for Bayesian meta-analysis. TABULATION, INTEGRATION, AND RESULTS: Two reviewers independently extracted data and assigned overall quality ratings based on predetermined criteria. Among women with prior preterm birth and a singleton pregnancy (five randomized controlled trials), progestogen treatment decreased the median risk of preterm birth by 22% (relative risk [RR] 0.78, 95% Bayesian credible interval 0.68–0.88) and neonatal death by 42% (RR 0.58, 95% Bayesian credible interval 0.27–0.98). The evidence suggests progestogen treatment does not prevent prematurity (RR 1.02, 95% Bayesian credible interval 0.87–1.17) or neonatal death (RR 1.44, 95% Bayesian credible interval 0.46–3.18) in multiple gestations. Limited evidence suggests progestogen treatment may prevent prematurity in women with preterm labor (RR 0.62, 95% Bayesian credible interval 0.47–0.79) and short cervix (RR 0.52, 95% Bayesian credible interval 0.36–0.70). Across indications, evidence about maternal, fetal, or neonatal health outcomes, other than reducing preterm birth and neonatal mortality, is inconsistent, insufficient, or absent. CONCLUSION: Progestogens prevent preterm birth when used in singleton pregnancies for women with a prior preterm birth. In contrast, evidence suggests lack of effectiveness for multiple gestations. Evidence supporting all other uses is insufficient to guide clinical care. Overall, clinicians and patients lack longer-term information to understand whether intervention has the ultimately desired outcome of preventing morbidity and promoting normal childhood development.

Evidence to inform decisions about maternal-fetal surgery: technical brief.

OBJECTIVE: To summarize the state of research in maternal–fetal surgery regarding the surgical repair of abnormalities in fetuses in the womb. DATA SOURCES: We searched MEDLINE from 1980 to 2010 for studies of maternal–fetal surgery for the following conditions: twin–twin transfusion syndrome, obstructive uropathy, congenital diaphragmatic hernia, myelomeningocele, thoracic lesions, cardiac malformations, and sacrococcygeal teratoma. METHODS OF STUDY SELECTION: We used pilot-tested data collection forms to screen publications for inclusion and to extract data. We compiled information about how fetal diagnoses were defined, maternal inclusion criteria, type of surgery, study design, country, setting, comparators used, length of follow-up, outcomes measured, and adverse events. TABULATION, INTEGRATION, AND RESULTS: Two reviewers independently extracted data and discordance was resolved by a third party. Of 1,341 articles located, we retained 258 (comprising 166 unique study populations). Three studies were randomized controlled trials; the majority of the evidence was observational (116 case series [70%], 36 retrospective [22%], and 11 prospective [7%] cohorts). Twin–twin transfusion is the most studied condition, with 84 studies including 2,532 pregnancies. Fewer than 500 pregnancies are represented in the literature for each of the other conditions except congenital diaphragmatic hernia (n=503). Inclusion criteria were poorly specified. Outcomes typically measured were survival to birth, preterm birth, and neonatal death. Longer-term outcomes were sparse but included pulmonary, renal, and neurologic status and developmental milestones. Maternal outcome data were rare. CONCLUSION: Although developing rapidly, maternal–fetal surgery research has yet to achieve the typical quality of studies and aggregate strength of evidence needed to optimally inform care.