Pre-eclampsia and preterm birth in Reunion Island: a 13 years cohort-based study. Comparison with international data

Objectives: To assess the prevalence of preterm birth in pre-eclamptic deliveries in Reunion Island, a tropical overseas French department (departements d'outre-mer, DOM) and to compare this prevalence with that of international literature. Methods: All singleton live-born deliveries referred to three maternity centers in Reunion Island over 13 years were eligible. Data for comparison were found through searches of MEDLINE, bibliographies of identified studies, proceedings of meetings on pre-eclampsia and contact with relevant researchers. Incidence of pre-eclampsia, proportion of preterm (<37(0/7) weeks gestation), late (34(0/7)-36(6/7) weeks) and early (<34(0/7) weeks) preterm birth in pre-eclamptic deliveries were analyzed. Results: Pre-eclampsia occurred in 2.3% of 51 927 singleton live-born deliveries in Reunion Island. The prevalence of preterm birth among pre-eclamptic deliveries was 59.8% (28.6% late and 31.2% early preterm birth). Among identified reports, only one prospective study from Canada (1986-1995) described preterm and early preterm birth rates higher than Reunion Island. A cohort-based report from Guadeloupe, another tropical French DOM, showed a preterm birth prevalence of 60.9%, with 30.8% of early preterm birth. Conclusions: Predominance of early- or late-onset pre-eclampsia has huge geographical differences. Further investigations are required to address risk factors for preterm birth and early onset pre-eclampsia in French DOM.