A variety of conditions have been anecdotally ascribed to induced abortion, including subsequent reproductive complications. Since most women obtaining induced abortions are at the beginning of their reproductive life, the effect of induced abortion on subsequent reproduction becomes a very significant one. Our review of the literature confirms findings reported previously. First, except in the case where an infection complicates induced abortion, there is no evidence of an association between induced abortion and secondary infertility or ectopic pregnancy. Second, the risk of midtrimester abortion, premature delivery and low birthweight in women whose first pregnancy is terminated by vacuum aspiration is not higher than that in women in their first pregnancy or women in their second pregnancy whose first pregnancy was carried to term. However, the risk of having a premature delivery or a low birthweight baby tends to be higher (but not significantly) among women whose first pregnancy is terminated by induced abortion when compared with women in their second pregnancy than when compared with women in their first pregnancy. This suggests that an induced abortion does not protect a women against the known risk of low birthweight for first-born offspring. Finally, women whose pregnancy is terminated by dilatation and evacuation may have an increased risk of subsequent premature delivery and a low birthweight baby. Very little has been published and no conclusions can be made regarding the effects of instillation procedures and repeat abortions on future reproduction. In conclusion, except for the association between pregnancies following dilatation and evacuation procedures and premature delivery and low birthweight, no significantly increased risk of adverse reproductive health has been observed following induced abortion.
PIP: This is an updated review of the literature on the risks of impaired future fertility due to induced abortion, emphasizing large studies on pregnancy termination by vacuum aspiration in the 1st trimester. Anecdotal reports have implicated abortion in causing sterility, menstrual disorders, psychiatric sequelae, and increased premature births, tubal pregnancies, stillbirths, birth defects and spontaneous abortions. Except when an infection complicates induced abortion, there is no evidence of an association of abortion with secondary infertility or ectopic pregnancy. The risk of midtrimester spontaneous abortion, premature delivery and low birthweight is not higher in the subsequent 1st term pregnancy. Studies using women in their 2nd pregnancy as controls, rather than controls in their 1st term pregnancy, however, report a slight but not significant increase in risk of prematurity or low birthweight. The 1st pregnancy is known to have an inherent higher risk of low birthweight. Induced abortion by dilatation and evacuation may confer a higher risk of subsequent premature delivery and low birthweight. Very little information is available comparing the various types of instillation abortions and numbers of repeat abortions on future reproduction. No added risks have been found for many conditions such as placenta previa, mental illness, pre-eclampsia, disproportion, hemorrhage, trauma, operative delivery or fetal distress. Anemia of pregnancy has been found to occur less often after abortion while urinary tract infections are significantly increased.