Abortion can affect fertility in several ways. Firstly, after induced abortion, the uterine cavity can be damaged. The cavity of the uterus is lined by the endometrium. This lining is composed of two layers, the functional layer (adjacent to the uterine cavity) which is shed during menstruation and an underlying basal layer (adjacent to the myometrium), which is necessary for regenerating the functional layer. Trauma to the basal layer, typically after a dilation and curettage performed after a miscarriage, or for surgical termination of pregnancy, can lead to the development of intrauterine scars resulting in adhesions that can obliterate the cavity to varying degrees. In the extreme, the whole cavity can be scarred and occluded. Even with relatively few scars, the endometrium may fail to respond to estrogen. This condition characterized by adhesions and/or fibrosis of the endometrium is called Asherman’s syndrome. The adhesions in uterus can lead to repeated pregnancy loss due to implantation of embryo to the scar tissue or wrong implantation of placenta, which can cause the abortion because of lack of blood supply to the developing embryo.
In rare cases the abortion is not complete and fetal bone remain in woman’s body. Unwanted contraception through prolonged retention of fetal bone is a cause of infertility. It is usually associated with a history of abortion, either spontaneous or induced. It is recommended a transvaginal ultrasound or hysteroscopy on every patient with a history of secondary infertility following abortion, regardless of the interval between the preceding termination and presentation.