摘要
Abstract Objective To determine the influence of maternal body weight before pregnancy and maternal weight gain during pregnancy on pregnancy outcome. Methods A total of 2584 primiparae with single pregnancy were enrolled in the study from July 1,1993 to June 30,1996 at Qingdao Municipal Hospital. Maternal height and weight before pregnancy were obtained by interview at the first prenatal visit and maternal weight gain was measured routinely at each prenatal visit. Body mass indices (BMIs) before and during pregnancy (at gestational weeks 12, 20, 24, 28, 32, 36, and 40) were calculated by the formula: BMI=body weight/height 2 (kg/m 2). Maternal BMIs from the 10th to the 90th percentile were considered as normal BMI, those below the 10th percentile as low BMI, and those above the 90th percentile as high BMI. According to their heights, all women were divided into 11 groups, namely, ≥1.54 and <1.56, ≥1.56 and <1.58, ≥1.58 and <1.60, ≥1.60 and <1.62, ≥1.62 and <1.64, ≥1.64 and <1.66, ≥1.66 and <1.68, ≥1.68 and <1.70, ≥1.70 and <1.72,≥1.72 and <1.74,and ≥1.74 and ≤1.76 m. Birth weight was measured immediately after delivery. In different maternal height groups, birth weights from the 10th to the 90th percentile were considered appropriate for gestational age (AGA), those below the 10th percentile were small for gestational age (SGA), and those above the 90th percentile were large for gestational age (LGA). All women were followed up for pregnancy outcomes. The incidences of pregnancy induced hypertension (PIH), operative delivery, LGA, and SGA were compared between the 3 groups of maternal BMI. Results Maternal BMI increased with the increase of gestational age, especially in the second half stage of gestation. The 10th and 90th percentiles of maternal BMI were 18.0 and 23.8 kg/m 2, respectively, before pregnancy, 19.3 and 25.8 kg/m 2, respectively, at 20 weeks of gestation, and 23.7 and 31.0 kg/m 2, respectively, at 40 weeks of gestation. Birth weight increased with the increase of maternal height, with the 10th and 90th percentiles being 2750 and 3800 g, respectively, in the group with maternal height ≥1.54 and <1.56 m, and 3200 and 4250 g, respectively, in the group with maternal height ≥1.74 and ≤1.76 m. The incidences of PIH, operative delivery, and LGA were significantly higher in the high BMI group, and the incidence of SGA was significantly higher in the low BMI group, than in the normal BMI group, either before pregnancy or at different gestational ages. At 40 weeks of gestation, the incidences of PIH, operative delivery, and LGA in the high BMI group were 10.0% (22/220), 29.5% (65/220), and 26.4% (58/220), respectively, compared with 1.2% (25/2041, P<0.01), 18.6% (380/2041, P<0.01), and 10.7% (218/2041, P<0.05), respectively, in the normal BMI group. Meanwhile, the incidences of SGA and LGA in the low BMI group were 18.2% (36/198) and 2.0% (4/198), respectively, compared with 3.2% (65/2041, P<0.05) and 10.7% (218/2041, P< 0.05), respectively, in the normal BMI group. Conclusion BMI before pregnancy and weight gain for height during pregnancy are valuable indices for predicting pregnancy outcome. Abnormal patterns of BMI can be found by calculating BMI at the initial prenatal examination and monitoring weight gain in the following regular prenatal care, and appropriate interventions can be taken to get good course and outcome of pregnancy.
Abstract Objective To determine the influence of maternal body weight before pregnancy and maternal weight gain during pregnancy on pregnancy outcome. Methods A total of 2584 primiparae with single pregnancy were enrolled in the study from July 1,1993 to June 30,1996 at Qingdao Municipal Hospital. Maternal height and weight before pregnancy were obtained by interview at the first prenatal visit and maternal weight gain was measured routinely at each prenatal visit. Body mass indices (BMIs) before and during pregnancy (at gestational weeks 12, 20, 24, 28, 32, 36, and 40) were calculated by the formula: BMI=body weight/height 2 (kg/m 2). Maternal BMIs from the 10th to the 90th percentile were considered as normal BMI, those below the 10th percentile as low BMI, and those above the 90th percentile as high BMI. According to their heights, all women were divided into 11 groups, namely, ≥1.54 and <1.56, ≥1.56 and <1.58, ≥1.58 and <1.60, ≥1.60 and <1.62, ≥1.62 and <1.64, ≥1.64 and <1.66, ≥1.66 and <1.68, ≥1.68 and <1.70, ≥1.70 and <1.72,≥1.72 and <1.74,and ≥1.74 and ≤1.76 m. Birth weight was measured immediately after delivery. In different maternal height groups, birth weights from the 10th to the 90th percentile were considered appropriate for gestational age (AGA), those below the 10th percentile were small for gestational age (SGA), and those above the 90th percentile were large for gestational age (LGA). All women were followed up for pregnancy outcomes. The incidences of pregnancy induced hypertension (PIH), operative delivery, LGA, and SGA were compared between the 3 groups of maternal BMI. Results Maternal BMI increased with the increase of gestational age, especially in the second half stage of gestation. The 10th and 90th percentiles of maternal BMI were 18.0 and 23.8 kg/m 2, respectively, before pregnancy, 19.3 and 25.8 kg/m 2, respectively, at 20 weeks of gestation, and 23.7 and 31.0 kg/m 2, respectively, at 40 weeks of gestation. Birth weight increased with the increase of maternal height, with the 10th and 90th percentiles being 2750 and 3800 g, respectively, in the group with maternal height ≥1.54 and <1.56 m, and 3200 and 4250 g, respectively, in the group with maternal height ≥1.74 and ≤1.76 m. The incidences of PIH, operative delivery, and LGA were significantly higher in the high BMI group, and the incidence of SGA was significantly higher in the low BMI group, than in the normal BMI group, either before pregnancy or at different gestational ages. At 40 weeks of gestation, the incidences of PIH, operative delivery, and LGA in the high BMI group were 10.0% (22/220), 29.5% (65/220), and 26.4% (58/220), respectively, compared with 1.2% (25/2041, P<0.01), 18.6% (380/2041, P<0.01), and 10.7% (218/2041, P<0.05), respectively, in the normal BMI group. Meanwhile, the incidences of SGA and LGA in the low BMI group were 18.2% (36/198) and 2.0% (4/198), respectively, compared with 3.2% (65/2041, P<0.05) and 10.7% (218/2041, P< 0.05), respectively, in the normal BMI group. Conclusion BMI before pregnancy and weight gain for height during pregnancy are valuable indices for predicting pregnancy outcome. Abnormal patterns of BMI can be found by calculating BMI at the initial prenatal examination and monitoring weight gain in the following regular prenatal care, and appropriate interventions can be taken to get good course and outcome of pregnancy.
