Do normal-weight women pregnant with twins are at the lowest risk of developing preeclampsia?

OBJECTIVE

To determine the relation between preeclampsia (PE) and pregravid body mass index (BMI) in twin pregnancy.

METHODS

Retrospective cohort study of 542 women pregnant with twins.

RESULTS

Forty-nine patients developed PE (9%). Underweight, overweight and obese women were at a higher risk of PE than normal-weight mothers. There was no linear (p = 0.7) but significant U-shaped relation between BMI and PE (p < 0.006). The lowest risk of PE development was related to BMI of about 23 kg/m2.

CONCLUSIONS

Nonlinear relation between PE occurrence and BMI suggests that using homogeneous PE risks of BMI groups may be incorrect.