I am 31 and was diagnosed with endometriosis four years ago. I had several surgeries and also had Lupron for nine months two years ago. I recently had surgery and then had two IUIs with no success. Blood tests confirm that I am ovulating, but now my doctors are saying they're not sure I am releasing the eggs. They say that maybe I am going through all the steps, but that maybe the eggs are getting trapped -- that the physiological part is working, but the mechanical part is not. I just don't understand. If I am going through all the steps, and blood levels show a release, and my tubes are open, what's the problem?

B.

Your doctors are talking about a problem with the follicle, the structure on the ovary in which an egg grows. Failure of the follicle to release the egg on cue is commonly called LUF, or luteinized unruptured follicle syndrome. I am not sure, however, that this condition really exists.

For one thing, it's not clear whether we can tell with certainty whether or not your ovary releases the egg. One typical way to check for ovulation is to look for an increase in progesterone levels in the blood. A functioning, mature follicle that has been exposed to the hormones LH or HCG will produce progesterone, so the increase in this hormone typically indicates ovulation. However, the ovary will produce progesterone whether or not the egg in the follicle is actually released.

Another method suggested to determine ovulation is an ultrasound. But this too is not very accurate. In one study, women who failed to demonstrate evidence of ovulation on ultrasound underwent laparoscopic surgery to view the ovary. The majority showed evidence that they actually had ovulated after all. And of those whose ovaries showed no sign of ovulation, 50 percent ended up pregnant in that very cycle. So, we can't bet our hat that LUF is occurring even when the ultrasound suggests no rupture of the follicle.

In fact, I am not really sure you have a problem. Without assessing your case personally, I cannot make a prediction. But assuming that you are not taking injections, that you have been trying to conceive for three years, and that you have endometriosis but no other fertility factors, your odds of conception would be only about 5 percent each month. The use of ovulation induction injections and intrauterine insemination could increase those odds to about 20 percent each month.

It is frustrating when we cannot identify a problem other than endometriosis. When this is the case, we move to empirical therapy. We try to determine the odds of conception without treatment. We know how effective certain treatments can be, so we review these options together with your own odds to see which approach is suitable for each case.