Prevalence and risk factors for prelabor rupture of the membranes (PROM) at or near term in an urban Swedish population

Abstract

Aims: To determine the prevalence, recurrence rate and to identify risk factors for prelabor rupture of the membranes (PROM) after 34 completed weeks in an urban Swedish population.

Methods: In a retrospective cohort study a sample of 2880 women aged 25–41 years, resident in the city of Göteborg, was randomly selected from the population register. According to information from the national Medical Birth Register (MBR), 1507 of these 2880 women had given birth 2736 times. 2270 of these deliveries had occurred in hospitals in the city of Göteborg and case records for 2242 of these deliveries were found. The case records were systematically analyzed for the occurrence of PROM and potential risk factors for PROM. 2208 of these deliveries occurred after 34 weeks of gestation. The further analyses were based on these 2208 deliveries.

Results: The prevalence of PROM after 34 week of gestation in this urban Swedish population was 12.9% and about 20% of the women in the population had experienced PROM at least once. In the multiple stepwise regression analysis, risk factors for PROM were primiparity, premature contractions, PROM in a previous pregnancy and bleeding in the first trimester.

Conclusions: PROM is a common complication at or near term. The risk factors for PROM found in this representative study are difficult to influence and thus provide no guidance about how pregnancies should be managed to reduce the occurrence of PROM in the future.