21 White coat hypertension in pregnancy: High incidence rates of gestational hypertension and preeclampsia

Abstract

Aim (1) To investigate what fraction of hypertension (HT) is white coat hypertension (WCH) in pregnant women without a past history of HT, (2) to compare the incidence rates of preeclampsia (PE) among normal pregnant women showing normal blood pressure (controls), WCH, and chronic hypertension (CH), and (3) to compare the incidence rates of gestational hypertension (GH) between controls and WCH. Methods This is a retrospective cohort study in 2934 pregnant women, who sought maternal checkup at Results (1) In 2934 women, 41 women had a past history of WCH ( n =3), and CH ( n =38). In the remaining 2893 women, 2837 women (98.1%) were normal blood pressure, 36 women (1.2%) were WCH, and 20 women (0.7%) were CH, thus, the prevalence of WCH in newly diagnosed HT in pregnancy was 64% (36/56). (2) The incidence rates of PE in controls, WCH, and CH were 1.7% (48/2,837), 15% (6/39), and 21% (12/58), respectively; the incidence rates of PE in WCH and CH were significantly higher than in controls ( p p p =0.600). (3) The incidence rate of GH in WCH was significantly higher than in controls (23% (9/39) vs. 1.3% (37/2,837), p Conclusions Almost two-third of the newly diagnosed HT in pregnancy was WCH. Therefore, the precise diagnosis of WCH is essential to avoid unnecessary anti-hypertensive therapy. The incidence rate of hypertensive disorders of pregnancy (PE plus GH) in women with WCH was 38%. Therefore, we should recognize WCH as very high risk for GH or PE, and should monitor women with WCH by HBP very carefully.