Problems with a woman's uterus and/or cervix may be caused by:

• Abnormalities of the uterus present from birth.
• Previous surgery or a procedure, such as a cervical cone biopsy or a dilation and curettage (D&C), which may decrease fertility if these procedures have damaged the cervix or uterine lining (rare).
• Exposure to certain drugs before birth, such as DES, which may cause deformities of the uterus, resulting in infertility.
• Abnormalities in a woman's cervical mucus, which may affect the movement of sperm through the vagina and cervix.
• Antibodies to sperm present in a woman's cervical mucus, which may kill the sperm or affect their ability to move normally and result in infertility.