An infertility treatment center is offering a free cycle of in vitro fertilization to couples interested in participating in a study of a drug designed to help the procedure work.

The Fertility Centers of Illinois is participating in a clinical trial of "an investigational drug for progesterone supplementation." Progesterone supports pregnancy, and progesterone supplementation is commonly used with in vitro fertilization.

Subjects who meet the study criteria will be provided one cycle of in vitro fertilization (IVF) at no cost. An IVF cycle is valued at $10,000.

After successful IVF stimulation and egg retrieval, half of the subjects will be randomly put into a group taking an FDA-approved progesterone drug, and the other half will take the investigational drug, FCI said.

Doctors are seeking up to 200 patients to take part in the study.

For more information about the application process and study criteria, visit www.fcionline.com.