Infertility

Controlling the risks of multiple gestation pregnancy

If you are taking ovulation medication combined with intercourse or IUI, and your physician determines that too many follicles are developing during your cycle, you may be told to stop taking medications for a few days (known as "coasting"), which may lower the risk of overstimulation of your ovaries. The physician may also suggest that you cancel the cycle and not take the hCG shot (brand names Novarel, Pregnyl, Profasi) that would trigger the release of eggs from the follicles. It is important to know, however, that a woman may still ovulate and conceive without taking the hCG shot, so the only safe way to avoid multiple gestation would be not to have intercourse during that cycle. While abstinence may be very difficult, especially if you have been trying to have a baby for some time, talk with your physician about the risk of multiple gestation even in the case when the "trigger" hCG shot is not given.

Before starting an ART cycle, it is important to have a discussion with your physician about the number of embryos (or eggs in the case of gamete intrafallopian transfer, or GIFT) that will be transferred to the uterus (or fallopian tubes for GIFT). Factors that affect the decision about the number of embryos the physician will transfer are the woman's age at the time of egg retrieval, estrogen levels during the stimulation³ and the number and quality of embryos created. Extra embryos can be frozen (cryopreserved) for pregnancy attempts in future cycles. The number of thawed embryos to transfer during a frozen/thawed embryo transfer cycle should be determined by the woman's age at the time of egg retrieval and the quality of embryos after they are thawed.

In November 1999, the American Society for Reproductive Medicine (ASRM) issued revised practice guidelines to assist clinics and their patients in determining the appropriate number of embryos to transfer during a cycle of ART. The guidelines encourage clinics to generate and use their own data regarding patient characteristics and the number of embryos to transfer in order to maximize pregnancy and live birth rates while minimizing the risks of multiple gestation pregnancy and multiple birth.

In the absence of data generated by the clinic, the ASRM guidelines recommend that for women with the most favorable outlook for pregnancy, no more than two good quality, fresh embryos should be transferred in a cycle in order to minimize the risk of higher order multiple gestation. Women with the most favorable outlook for pregnancy include those who are under the age of 35 and who produce enough high quality embryos to use cryopreservation for those embryos that are not transferred during the fresh embryo cycle. The guidelines suggest the transfer of more embryos as the outlook for pregnancy declines with the woman's age or embryo quality analysis.

Ask your physician how the guidelines relate to your case. The guidelines also recommend that the number of embryos to transfer should be agreed upon by the physician and the patient and made part of the informed consent document and clinical record.

One relatively new laboratory technique is to culture embryos for five days, or until they reach the blastocyst stage. Early studies have shown that fewer blastocyst stage embryos can be transferred while good implantation and pregnancy rates are maintained. This procedure may help reduce the risk of multiple gestation pregnancy during ART. Ask if you are a candidate for blastocyst transfer. (Some women, especially older women or women who produce few embryos, may not be good candidates for this procedure.)

^{3 Pasqualotto, E.B., MD, Flacone, T., MD, et al. Risk factors for multiple gestations in women undergoing insemination with ovarian stimulation. Fertility and Sterility, 72:4, October, 1999 pp. 613-618.}

Source: This information is used with permission and courtesy of RESOLVE, the National Infertility Association.