A prospective multicenter cohort study to evaluate effects of prior induced termination of pregnancy on complications and pregnancy outcomes.
women have induced abortion in early pregnancy (<12 weeks of gestation).
permanent population and no tendency to move.
normal language expression and understanding ability, able to understand research content.
be able and willing to provide written informed consent and effective contact information, and be willing to cooperate with follow-up investigations.
above the age of 40
with history of adverse pregnancy and childbirth