Abstract: Gestational obesity and correlative abortion are becoming the focus. In those infertile women, obese women have higher risk of abortion. So, obese women are suggested to control well their weight before pregnancy. In those women with natural pregnancy, obese women have also increased risk of abortion. Most studies showed that the endocrine disorders related with obesity were the main mechanism of abortion. Most obese patients are accompanied with hyperinsulinism and insulin resistance, while the plasminogen activator inhibitor-1 （PAI-1）, androgen and insulin-like growth factor play different roles in the pathophysiology. In addition, the decreased uterine receptivity, the reduced endometrial blood flow and abnormal karyotype are reasons of abortion in obese women. In this paper, the mechanism of abortion in obese women was reviewed.

Key words: Obesity, Abortion, Body mass index, Insulin resistance