New tool helps predict pregnancy outcomes

Feb 23 2006

Physicians must consider a number of variables when treating couples who cannot naturally conceive because of factors involving both the woman and man. However, a new tool developed at the University of Iowa helps experts better predict outcomes and choose the treatment method that is most likely to help the couple achieve pregnancy.

The model applies when a woman's own eggs can be used for an advanced form of in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), in which a single sperm cell is injected into the female's egg. The model takes into consideration the woman's age, factors that cause the man's infertility, the choice of three different sperm retrieval methods and the choice of using fresh or frozen sperm.

The computational model was created by Moshe Wald, M.D., assistant professor of urology in the UI Roy J. and Lucille A. Carver College of Medicine, and based on previous research and software developed by Craig Niederberger, M.D., associate professor of urology and chief of andrology at the University of Illinois at Chicago College of Medicine.

"It has been difficult to predict whether pregnancy will be achieved for couples when different factors are at play. We designed this computational model to help the physician who is planning IVF/ICSI for patients. The physician may use the model to plan the best approach and counsel the patients appropriately," said Wald, who trained under Niederberger and specializes in male infertility.

"The model is not designed for direct use by couples seeking fertility assistance, especially because some of the information required to use the model is technical and not available to the lay public," Wald added.

To use the model, physicians complete an online form and receive an automatic assessment. The data submitted includes information about the man's infertility problem, such as whether it relates to sperm production or an obstruction that prevents sperm from being transported outwards. Certain factors cannot be changed, such as a woman's age.

"All things being equal, the younger a female is, the higher the chances for fertilization and a successful pregnancy. On the other hand, if that particular female's partner has bad sperm parameters, then the chances might not be as good. The model takes into consideration both the woman's and man's factors and integrates all the various parameters to give a certain prediction," Wald said.

Two of the methods for sperm retrieval included in this model require anesthesia and must be done in an operating room; the other method can be done without anesthesia in a regular clinic setting. The computational response can help experts decide which of the three methods is best to use for sperm retrieval in a particular setting, and whether it might make a difference if fresh or frozen surgically retrieved sperm is used. For example, if either type is likely to produce the same outcome, then the doctor may choose frozen, which is more convenient.

"When we use fresh sperm, the surgical procedures for the sperm retrieval and egg retrieval need to be done the same day, and this may not be convenient for the couple. However, if we use frozen sperm, the man can have his procedure first, and if we find sperm, we can bank it. Then, at the couple's convenience we do egg retrieval and the fertilization procedure that puts the egg and sperm together. The model helps us know in advance when frozen sperm would allow for good results for that couple," Wald said.

A different study led by Wald and based on earlier work with Niederberger at Chicago adds evidence that for many couples frozen sperm is just as effective as fresh sperm when used in IVF/ICSI procedures. That finding appeared in the January/February 2006 issue of the Journal of Andrology.

Wald first introduced the computational model in an article that appeared in the September 2005 issue of the journal Reproductive BioMedicine Online. In addition to Wald and Niederberger, contributors to that paper included Jay Sandlow, M.D., associate professor of urology at the Medical College of Wisconsin in Milwaukee, and researchers in the UI Department of Obstetrics and Gynecology: Amy Sparks, Ph.D., research scientist; Craig Syrop, M.D., professor; and Brad Van Voorhis, M.D., professor.