My husband and I have been trying to conceive for a year now without success. He had undergone head radiation for a benign tumor, but developed secondary adrenal insufficiency, hypogonadism and hypothyroidism from pituitary damage from radiation. He is on all the replacement medications. Could this be a cause of our problem? Also he takes narcotic pain medications daily for headache from the tumor. We are anxious to start a family.

--Emily

You did not say whether your husband has had his semen tested. This should be your first step.

Assuming a semen analysis has been performed and is abnormal, then pituitary insufficiency may very well be the cause of your infertility problems. Radiation can result in decreased blood flow to the pituitary. This interferes with normal production and release of the hormones FSH and LH, which stimulate the testicle to produce sperm and the hormone testosterone. In addition, narcotics can also reduce pituitary activity.

To confirm the diagnosis, you need to evaluate the levels of FSH, LH and testosterone. In men with pituitary insufficiency they will all be low. Examination will reveal smaller and softer testicles. Luckily, pituitary insufficiency can usually be treated successfully.

Treatment often begins with injections of the hormone hCG three times per week. After three to six months the testosterone level will be normalized. At that point another semen analysis is done. If improvement is noted, you can continue this treatment and try for pregnancy. If sperm production hasn't improved, you might begin injections of the hormone FSH (Gonal-F or Follistim). This medication is more expensive than hCG, and that is why replacement with hCG is attempted first.

It's worth noting that many women conceive with levels of motile sperm that would normally be considered too low to result in pregnancy. If sperm are produced but the numbers or motility are too low, IVF and ICSI (sperm injection) would be the next step. After pregnancy is achieved, your partner needs to speak with his physician to work out testosterone replacement to maintain normal sexual function.