Inverse association of prepregnancy systolic blood pressure and live birth rate in normotensive women undergoing in vitro fertilization/intracytoplasmic sperm injection.

ABSTRACT

OBJECTIVE: To explore whether maternal baseline systolic blood pressure (SBP) and diastolic blood pressure (DBP) affect pregnancy outcomes particularly in normotensive women (SBP, 90-139 mm Hg; DBP, 60-89 mm Hg) and hypertensive women undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). DESIGN: Retrospective cohort study. SETTING: Maximum care hospital for reproductive medicine. PATIENT(S) This study included 73,462 patients who underwent IVF/ICSI at the Reproductive and Genetic Hospital of CITIC-Xiangya between January 1, 2016, and November 30, 2020, selected on the basis of pre-established criteria. Analysis was limited to the first transfer cycle of the first stimulation cycle. INTERVENTION Baseline SBP and DBP. MAIN OUTCOME MEASURE(S) The primary outcome focused on the live birth rate (LBR), with the secondary outcomes including clinical pregnancy rate, ectopic pregnancy rate, first-trimester miscarriage rate, second- or third-trimester fetal loss, and delivery/neonatal/maternal outcomes. Analytic methods included Poisson regression, linear regression, linear mixed-effect model, and restricted cubic spline analysis as appropriate. RESULT(S) For normotensive women, a 10-mm Hg increase in SBP was associated with an adjusted relative risk of 0.988 (95% confidence interval, 0.981-0.995) for live birth likelihood. However, DBP was not significantly associated with LBR after adjustments. The secondary outcomes indicated that increases in SBP and DBP were associated with higher risks of first-trimester miscarriage, gestational diabetes mellitus, and gestational hypertension in the normotensive subset. Sensitivity analyses confirmed these associations between SBP/DBP and LBR, consistent with the main findings even under stricter guidelines and after adjusting for multiple confounders. Subgroup analyses showed variation in the impact of blood pressure on LBR across different demographics and conditions. Consistent with earlier studies on blood pressure and birth outcomes, we found a 10-mm Hg increase in SBP was associated with a 5.4% (adjusted relative risk per 10 mm Hg, 0.946; 95% confidence interval, 0.907-0.986) reduction in LBR in the hypertensive subgroup. CONCLUSION(S) Systolic blood pressure impacted LBR outcomes in normotensive women who underwent IVF/ICSI, which suggests the need for reconsidering blood pressure management guidelines for reproductive-age women, focusing on reproductive health in addition to cardiovascular risk.