Beating the clock? Frozen ovaries make headlines
This article first appeared in the St. Louis Beacon: November 14, 2008 - More women are waiting to start their families, delaying pregnancy until their mid- to late-30s, 40s and beyond. While pregnancy in a woman's later years can carry some complications, "the biggest risk of delaying pregnancy is not being able to get pregnant at all," said Dr. Jill Powell, assistant professor of medicine in the department of obstetrics, gynecology and women's health at Saint Louis University School of Medicine. "We see all these celebrities having babies - even twins - in their 40s, and we take it for granted that we will be able to do it too."
Powell cautions that women will experience a big drop in fertility beginning around age 38. It then falls more precipitously 40. And if pregnancy is achieved (whether spontaneously or with the help of reproductive technologies such as in-vitro fertilization), these women still require close supervision. Pregnancies after age 35 bring additional risk for maladies such as diabetes or high blood pressure, Powell said. And these conditions may not surface until some point during the pregnancy.
St. Louis' Dr. Silber Makes Women's Health History
One bright spot has surfaced in the field of fertility and it started here in St. Louis. The ability to freeze and transplant ovaries is a new option for women facing cancer therapy or for those women who want to delay pregnancy until later years. Dr. Sherman Silber, director of the Infertility Center at St. Luke's Hospital, made international headlines with research presented this month at the annual meeting of the American Society of Reproductive Medicine (ASRM) held in San Francisco.
"We can transplant ovaries without any loss of ovarian tissue or eggs, and it functions perfectly normally whether it's fresh or frozen," Silber said. He and his team performed a ground-breaking trial in which they transplanted an identical twin's ovary to her twin sister. A year later, the transplant recipient successfully conceived a child. The twin receiving the transplant had previously been unable to conceive due to premature ovarian failure, commonly defined as the loss of ovarian function (and therefore, fertility) before the age of 40.
While the details of this case are intriguing -- one twin helping another to achieve motherhood -- the real breakthrough, according to Silber, is the science. "We can freeze the ovaries of young women who are going to lose their fertility over time and transplant them back later, and they (the ovaries) won't have aged," he said.
Providing Hope for Young Women with Cancer
The breakthrough offers hope for women undergoing reproductively-destructive therapies, such as women with cancer facing chemotherapy or radiation. "If we take the ovary out, freeze it, save it and transplant it back later, they will be fertile again," Silber noted.
This new application builds on current science that allows women to have their eggs frozen. "But freezing the ovary and putting it back is much more sure for the patient than egg freezing," asserted Silber. "If you put all those eggs in one basket, and she goes through in-vitro fertilization, she can't have any better chance of pregnancy than 50 percent. If she is not pregnant from that, then she's finished."
Other research presented at this month's ASRM conference included a case study of one woman who had her ovary removed, frozen and then restored by Silber's team, a procedure they have performed nine times.
The Race Against Time: A Losing Battle?
Though the aging of ovaries can now be delayed, aging affects all parts of a woman's biology and physiology. And "a lot of complications seen in pregnancy in women of later childbearing years are occurring or worsening in part because of the mother's age," says Powell. "This is because these co-existing medical conditions are more likely to happen the older you are when you become pregnant."
Dr. Cindy Haines is managing editor of Healthday-Physician's Briefing and president of Haines Medical Communications Inc., a full-service medical communications and consulting firm. As a board-certified family physician, Haines is well-versed in all areas of health care, with particular interest in fitness, nutrition, and psychological health.