Abstract: We included three studies involving 275 women (data reported for 271) with PPROM at up to 34 weeks' gestation. All three studies were conducted in the United States. Each study investigated different methods of fetal assessment. One study compared weekly endovaginal ultrasound scans with no assessment (n = 93), one compared amniocentesis with no assessment (n = 47), and one compared daily nonstress testing with daily modified biophysical profiling (n = 135). We were unable to perform a meta-analysis, but were able to report data from individual studies. There was no convincing evidence of increased risk of neonatal death in the group receiving endovaginal ultrasound scans compared with the group receiving no assessment (risk ratio (RR) 7.30, 95% confidence interval (CI) 0.39 to 137.54; one study, 92 women), or in the group receiving amniocentesis compared with the group receiving no amniocentesis (RR 1.00, 95% CI 0.07 to 15.00; one study, 44 women). For both these interventions, we inferred that there were no fetal deaths in the intervention or control groups. The study comparing daily nonstress testing with daily modified biophysical profiling did not report fetal or neonatal death. Primary outcomes of maternal death and serious maternal morbidity were not reported in any study. Overall, there were few statistically significant differences in outcomes between the comparisons. The overall quality of evidence is poor, because participant blinding was not possible for any study. There is insufficient evidence on the benefits and harms of fetal assessment methods for improving neonatal and maternal outcomes in women with PPROM to draw firm conclusions. The overall quality of evidence that does exist is poor. Further high-quality randomised controlled trials are required to guide clinical practice.

Plain-language summary: This review was carried out to evaluate whether these methods lead to improved health outcomes for the mother and her baby. The review included three randomised controlled studies that involved a total of 275 women (data reported for 271) with PPROM at up to 34 weeks' gestation. All three studies were from the USA. They each investigated different methods of fetal assessment, so no meta-analysis could be conducted. Instead, the review reported the results of each individual study. One study compared weekly endovaginal ultrasound scans where the probe is placed inside the vagina versus no assessment, one compared an amniotic fluid test to measure levels of fetal lung surfactant with no assessment, and one compared a daily 'nonstress test' (recording the fetal heartbeat) with daily modified biophysical profiling (recording the fetal heartbeat as well as estimating the volume of amniotic fluid surrounding the baby). In each study, there were few statistically significant differences between groups in outcomes for the mother, fetus or neonate. The overall quality of the evidence was poor, because participants knew which group they were in. More studies are needed to assess the benefits and harms of fetal assessment methods for improving neonatal and maternal outcomes in women with PPROM before firm conclusions can be drawn.