Maternal weight and pregnancy complications.

The effect of obesity alone was investigated among 16,858 women who were delivered of their infants within a 12-month period. Complete analysis was possible for 9667 patients who were divided into four weight categories and separated into two groups, with and without complications. Perinatal mortality, infant size, and the primary cesarean delivery rate were calculated for each group. Among 2597 women with antenatal complications, there was a significant increase in perinatal mortality (p less than 0.001), primary cesarean delivery (p less than 0.02), and mean infant birth weight (p less than 0.01) in the obese and the morbidly obese gravid women. Among 7070 women without antenatal complications there was a significant increase in primary cesarean delivery (p less than 0.001) and mean infant birth weight (p less than 0.01) but not perinatal mortality in the obese and the morbidly obese gravid women. Obesity alone does not appear to affect the perinatal mortality rate but it increases the likelihood of cesarean delivery in the morbidly obese patient.