Increase in Systolic Blood Pressure of ≥ 30 mm Hg and/or Diastolic Blood Pressure of ≥ 15 mm Hg During Pregnancy: Is It Pathologic?

Abstract

Objective: To determine whether a rise in systolic blood pressure (SBP) ≥ 30 mm Hg and/or diastolic blood pressure (DBP) ≥ 15 mm Hg in the absence of hypertension during pregnancy is associated with adverse pregnancy outcomes. Method: We conducted a retrospective, longitudinal study of 1498 pregnant women without hypertension or proteinuria in the first trimester. The blood pressure levels measured during the first (7.8 ± 2.3 weeks), second (20.7 ± 1.2 weeks), and third trimesters (38.6 ± 1.5 weeks) were analyzed. The perinatal outcome was compared between women who exhibited a rise in SBP ≥ 30 mm Hg and/or DBP ≥ 15 mm Hg during pregnancy (large Δ BP group) and women who did not (small Δ BP group) using one way analysis of variance, chi‐square test, or Fisher's exact test. The contribution of gestational hypertension and a large Δ BP to the development of adverse pregnancy outcomes was evaluated using multivariate logistic regression analysis. Results: Of 1441 women who remained normotensive (SBP < 140 mm Hg and DBP < 90 mm Hg) during pregnancy, 238 (16.5%) and 1203 (83.5%) belonged to the large Δ BP and small Δ BP groups, respectively. There were no significant differences between the two groups in the occurrence rate of gestational proteinuria, preterm deliveries, low‐birth‐weight infants, or small‐for‐gestational age infants. A large Δ BP was not a risk factor in itself for the occurrence of gestational proteinuria or small‐for‐gestational age infants after controlling for the effect of gestational hypertension. Conclusion: A rise in SBP ≥ 30 mm Hg and/or DBP ≥ 15 mm Hg is not a risk factor of adverse outcome among women who remain normotensive during pregnancy.