WHO systematic review of maternal mortality and morbidity: the prevalence of uterine rupture.

OBJECTIVE To determine the prevalence of uterine rupture worldwide. DESIGN Systematic review of all available data since 1990. SETTING Community-based and facility-based reports from urban and rural studies worldwide. Sample Eighty-three reports of uterine rupture rates are included in the systematic review. Most are facility based using cross-sectional study designs. METHODS Following a pre-defined protocol an extensive search was conducted of 10 electronic databases as well as other sources. Articles were evaluated according to specified inclusion criteria. Uterine rupture data were collected along with information on the quality of reporting including definitions and identification of cases. Data were entered into a database and tabulated using SAS software. MAIN OUTCOME MEASURES Prevalence of uterine rupture by country, period, study design, setting, participants, facility type and data source. RESULTS Prevalence figures for uterine rupture were available for 86 groups of women. For unselected pregnant women, the prevalence of uterine rupture reported was considerably lower for community-based (median 0.053, range 0.016-0.30%) than for facility-based studies (0.31, 0.012-2.9%). The prevalence tended to be lower for countries defined by the United Nations as developed than the less or least developed countries. For women with previous caesarean section, the prevalence of uterine rupture reported was in the region of 1%. Only one report gave a prevalence for women without previous caesarean section, from a developed country, and this was extremely low (0.006%). CONCLUSION In less and least developed countries, uterine rupture is more prevalent than in developed countries. In developed countries most uterine ruptures follow caesarean section. Future research on the prevalence of uterine rupture should differentiate between uterine rupture with and without previous caesarean section.