Timing of delivery for women with non-severe hypertensive disorders of pregnancy

This thesis consists of two parts. Part I focusses on the HYPITAT-II study, which evaluated whether women with non-severe hypertensive disorders of pregnancy between 34 and 37 weeks of pregnancy should be delivered in an attempt to prevent complications, or monitored until 37 weeks to allow the unborn child to mature. The results show that any beneficial effect of immediate delivery on maternal outcomes is probably small. However, expectant monitoring clearly benefits the child. As quality of life did not differ between the two strategies and economic analyses favoured expectant monitoring as well, we concluded that expectant monitoring should be offered to women with non-severe hypertensive disorders of pregnancy between 34 and 37 weeks of gestation.
Part II discusses other aspects of timing of delivery for women with non-severe hypertensive disorders of pregnancy. First, we studied maternal and neonatal outcomes of women with chronic hypertension in pregnancy. The results show that these women have an increased risk of complications, which might be reduced by planned delivery between 39 and 40 weeks of pregnancy. Second, we explored the potential of so-called “individual patient data meta-analysis” to provide definitive and in-depth answers on timing of delivery for individual women with non-severe hypertensive disorders of pregnancy.
In conclusion, the work in this thesis indicates that immediate delivery does not benefit all women with non-severe hypertensive disorders of pregnancy. Additional research, using individual data from existing trials, is necessary to develop optimal management for individual women with these disorders.