[Effects of obesity and weight gain during pregnancy on obstetrical factors].

The relationship between the body weight or weight gain during pregnancy and various obstetrical factors was investigated in 731 patients who delivered in San-ikukai Hospital for in the year 1986. The patients were classified into three groups according to their body weight in non-pregnant states: slender (n = 214), ordinary (n = 379) and obese (n = 138), according to the standard for "The decision diagram for the estimation of obesity and emaciation in Japanese" published in 1986 by the Ministry of Health and Welfare, Japan. Each of these groups was further divided into two groups according to the degree of weight gain during pregnancy (more or less than 15kg). Then, the duration of labor, the blood loss during delivery, the birth weight, the placental weight and the obstetrical abnormalities (prolonged labor, arrested labor, blood loss of more than 500 ml, fetal distress and toxemia of pregnancy) were investigated in these groups. The blood loss, the neonatal birth weight and the placental weight in the obese groups were much greater than those in the ordinary or the slender group (p less than 0.005). However, there was no significant difference in the duration of the labor among these groups. The incidence of obstetrical abnormalities in the obese group was significantly higher than in the ordinary or the slender group (chi 2 = 4.37, p less than 0.05, chi 2 = 5.27, p less than 0.025).(ABSTRACT TRUNCATED AT 250 WORDS)