The American Society for Reproductive Medicine (ASRM) defines infertility as a disease of the reproductive system that impairs one of the body’s most basic functions: the conception and delivery of healthy children. Infertility may result from a patient’s “medical, sexual, and reproductive history, age, physical findings, or diagnostic testing,” and includes the need for medical intervention such as the use of donor eggs/sperm or donor embryos in order to become pregnant, either as an individual or as part of a couple.
In couples who are able to have regular intercourse, when the female partner is under the age of 35, the infertility evaluation should begin after 12 months of unprotected sex. For women over the age of 35, the infertility evaluation should begin after 6 months of unprotected intercourse due to the impact of age on fertility.
Conception is a complicated process that depends upon many factors: the production of healthy sperm by the male and healthy eggs by the female; and patent fallopian tubes for the sperm to reach and fertilize the egg and to allow for the embryo to travel to the uterus and attach. Finally, for the pregnancy to continue to full term, the woman’s hormonal environment must be able to support continued development. Infertility results when any of these processes are impaired.
After a complete fertility work-up, the cause of infertility can be determined in about 80% of the cases.
While about a third are attributed to the male and a third to the female, about a third are attributed to a combination of problems from both partners.
Male factor infertility can be caused by problems with sperm production, sperm function, sperm transport or sexual dysfunction. Prior vasectomy is also a common condition that can be easily treated. Most common male infertility factors are typically related to low sperm counts (oligospermia), poor sperm motility (asthenospermia) or malformed sperm (teratospermia). Other common causes include the complete lack of sperm in the ejaculate (azoospermia), which may be caused by abnormal transport of sperm or the lack of sperm altogether. A complete evaluation of the male partner is an important part of the initial infertility work-up.
Common causes of infertility attributed to the female include the failure to ovulate (release of the egg), blockage of the fallopian tubes and ovarian dysfunction/failure. Abnormalities of uterine function and pelvic conditions such as endometriosis can complicate normal conception. A complete work-up of the female will identify many of these problems.
Frequently, a couple’s problems are related to the combination of several factors. Several rather mild defects can combine to make reproduction inefficient or prevent it all together.
