Discovery By Fertility Specialist Offers Promise Of Reducing Multiple BirthsTied To Fertility...( prospective trial involving 24 women th...)

Successful infertility treatment depends on the ability to manipulate precisely the essential hormones involved, which requires their clear identification. Infertility specialists strive for a single birth, considering anything more than twins a complication, because of the potentially serious, even life-threatening, medical problems that often accompany multiple births.

One of the stumbling blocks to this end has been identifying a way to limit the number of eggs that mature during fertility treatment while keeping at least one egg developing.

During a normal menstrual cycle, FSH stimulates egg follicles to develop. At a certain point in the cycle, estrogen signals the pituitary to stop producing FSH, a signal that at least one egg follicle is well and being nurtured. The drop in FSH stops more follicles from developing, all immature follicles die, but the "recruited" follicle lives.

"Nobody knew why the follicle continued to thrive in the face of decreased FSH," Sullivan said. "We thought that FSH was required all the way along, even at low levels. So standard procedure during fertility treatment has been to continue FSH, which keeps follicles growing, but also may stimulate too many to develop. That's the up side and down side of FSH.

"We've now shown that FSH is not essential during the entire first half of the cycle. We've discovered that LH can make up for the deficiency of FSH as the follicle grows." '"/>

Contact: Lois Baker
baker@newsb.buffalo.edu
716-645-2626
University at Buffalo
13-Mar-1998