I am a 30-year-old woman, and I've been trying to conceive for four months without success. We have been using ovulation predictor kits for the past three months to time everything right. I know the rule is to wait 12 months before beginning fertility tests, but it is hard to wait that long knowing you could be wasting time. How long do you recommend trying before fertility evaluation can begin?

-- Tonya

The diagnosis of infertility is the inability to conceive a pregnancy after one year of attempting. The purpose of a time limit is too ensure that: (1) You do not get overly stressed when there is in fact no fertility problem. Stress can be a significant contributing factor to a couple's fertility problems. (2) You do not undergo needless testing. Tests can be costly, and insurance providers are unwilling to contribute significant resources when the likelihood that a problem exists is small.

The one-year timeframe was chosen because the monthly chance of conception varies from 8-20 percent per month, depending on your age. The risk of the biological clock ticking away your fertility is not really a concern until about age 38 for most women. So, unless there is an obvious fertility factor such as tied tubes, previous ectopic pregnancy, irregular menses or known semen analysis problems, you would do best simply to attempt pregnancy using ovulation test kits to "schedule" intercourse just prior to ovulation.

However, if you have a known fertility problem or are over age 38, you should consider an earlier evaluation. Those over 38 do best by consulting a fellowship-trained reproductive endocrinologist to improve the odds that a thorough analysis will be completed quickly and that all appropriate treatments are offered.