In rare cases, they can cause infertility by interfering with the endometrium, blocking the fallopian tubes, or altering the position of the cervix and preventing sperm from reaching the uterus. Weak or Abnormal Uterine Muscle Contractions One study indicated that many cases of female infertility may be due to weak contractions in the uterus. These contractions, which are strongest during ovulation, produce waves that move the sperm up toward the fallopian tubes. In some women, these waves are weak, infrequent, or actually move the sperm downward toward the cervix. Laparoscopic surgery is less likely to cause adhesions than standard open surgery.
Abortion performed under sterile conditions is very safe and carries few risks.
Frequent abortions, however, may impair a woman's fertility. The cervix can weaken and be unable to sustain a pregnancy. Scar tissue may form inside the uterine cavity after multiple abortions resulting in a closed uterus, known as Asherman's syndrome. Other Medical Causes of Infertility Women may find their fertility impaired by a number of medical conditions, including ruptured appendix, diabetes, kidney disease, thyroid disorders, and hypertension. Waiting for such a spontaneous abortion, however, increases the risk for dangerous and even life-threatening rupture of the fallopian tube.