The P4 study: Subsequent pregnancy maternal physiology after hypertensive and normotensive pregnancies

Hypertensive disorders of pregnancy are associated with subsequent increased risk of cardiometabolic disease. Adverse cardiometabolic measures are noted soon after hypertensive versus normotensive pregnancy (NP); to what degree these persist into a subsequent pregnancy (SP) is unknown. This study aimed to assess women's physiology early in SP after hypertensive pregnancy (HP: preeclampsia or gestational hypertension) or NP and compare SP to 6 months postpartum findings from the index pregnancy.

Prospective sub-study of the P4 (Postpartum, Physiology, Psychology and Paediatric) observational cohort. Measurements six months after NP versus HP, and the SP at 11-13 weeks gestation.

Blood pressure (BP), blood and urine tests (urine ACR, HOMA-IR, LDL cholesterol), body composition, and contribution of maternal characteristics and inter-pregnancy factors to BP and body fat (FM%) in SP.

49 women (34 NP, 15 HP). In the SP, post-HP women had higher BP (112/70 mmHg HP vs 102/64 mmHg NP; p < .001), with no significant drop from six months postpartum to early SP. On regression analysis, systolic and diastolic BP at 6-months were the major predictors for SP systolic (p < 0.001) and diastolic (p = 0.009) BP respectively in the SP. Longer interpregnancy interval and increased FM% 6-months postpartum were associated with higher SP FM% (p < 0.001).

BP and body fat six months postpartum were similar early in the SP for HP group, and postpartum BP and FM% were major predictors of their corresponding SP measurements. Postpartum/inter-pregnancy intervention programs to improve these cardiometabolic risk markers might help improve women's long-term health and require investigation.