KatCarney

Rosiglitazone may induce ovulation in metformin-resistant PCOS. (Small Study).
Author/s: Kate Johnson
Issue: Jan 1, 2002

ORLANDO, FLA. -- Rosiglitazone, an insulin-sensitizing agent, holds promise for ovulation induction in metformin-resistant polycystic ovary syndrome, results of a small study suggest.

"Probably half of PCOS [polycystic ovary syndrome] patients don't respond to metformin, and we are quite impressed with the way rosiglitazone has worked," Dr. Robert Casper, one of the study's investigators, said at the annual meeting of the American Society for Reproductive Medicine.

The study, which was presented in poster form, included five infertile women with PCOS who had failed to ovulate with clomiphene citrate (up to 150 mg/day) and at least one cycle of letrozole. The women had also failed to ovulate on a 6-month trial of metformin.

Rosiglitazone was given at 4 mg/day b.i.d.; it was discontinued when a pregnancy was confirmed. Spontaneous ovulation occurred in all patients during the first month of rosiglitazone treatment.

After one documented ovulation, fertility therapy was then individualized to include letrozole administration (2.5 mg/day on days 3-7) and/or midcycle administration of HCG.

Augmentation of ovulation resulted in pregnancy in two patients after 1 and 2 months, respectively Significant improvement in endocrine and metabolic parameters occurred in all patients after 1 month of rosiglitazone treatment.

"We think [rosiglitazone] could probably work in all PCOS patients," Dr. Casper said, explaining that there is some disagreement as to whether metformin really works in PCOS patients or whether it works indirectly simply by causing weight loss.

"The problem is that metformin has been around for a long time; it is known to be safe, although it has side effects; and it has also been used in pregnancy in some countries with no apparent effect," Dr. Casper, professor and head of reproductive sciences in the department of obstetrics and gynecology at the University of Toronto, said.

In contrast, although rosiglitazone has not shown any serious side effects, another glitazone-troglitazone--was recently pulled off the market because of hepatotoxicity, despite its similar beneficial effects on endocrine and metabolic functions, he said.

"If metformin is working in a patient [with polycystic ovary syndrome], I wouldn't switch--it's a tried and tested treatment--but on the other hand, if it isn't, I would recommend rosiglitazone," he said.

COPYRIGHT 2002 International Medical News Group

COPYRIGHT 2002 Gale Group

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