Effects of Obesity on Pregnant Women: Maternal Hemodynamic Change

Abstract

The purpose of this study is to clarify the effects of obesity on hemodynamic change in pregnant women. From 1322 primiparous women and 1027 multiparous women who delivered singleton babies with no life-threatening anomalies, 110 primiparous obese women, 1050 primiparous normal-weight women, 139 multiparous obese women, and 816 multiparous normal-weight women were selected according to body mass index at the first visit prior to the 10th gestational week. Women exhibiting chronic hypertension, over diabetes mellitus, and extreme skinniness were excluded. All of the women had been under the same management at Osaka City University Hospital. Their medical records were analyzed retrospectively. The study determined the arterial blood pressure of obese women to be significantly higher than that of normal-weight women throughout pregnancy in both primipara and multipara. The incidence of pregnancy-induced hypertension in obese women was significantly higher in primipara (22.7% versus 8.2%) and multipara (15.8% versus 5.0%). The incidence of intrapartum hypertension was also higher in the obese group. Hematocrit count at 3 gestational months (37.7 +/- 3.1 in primipara, and 37.6 +/- 2.7 in multipara) and 8 gestational months (34.4 +/- 2.7 in primipara, and 33.7 +/- 2.7 in multipara) were significantly higher than those in normal-weight women. Exercise tests using impedance cardiographs showed poor cardiac function in 5 of 17 obese women. These findings led us to conclude that obesity during pregnancy is clearly accompanied by hypertension, hemoconcentration, and poor cardiac function.