The other step we can routinely take is to encourage our patients to thoroughly examine the Society for Assisted Reproductive Technology's clinic-specific IVF data. Asking patients to step back and look at more than pregnancy rates could be the biggest key to reducing multiple gestations with IVF.
Multiples and Mortality
Infant mortality is a problem of major concern to the industrialized world, and it continues to be an important marker for assessing the health and welfare of countries. Despite the fact that the United States spends 15% of its gross national product on health care, it ranks 21st in the world in its infant mortality rate, below countries that spend much less.
The causes of our high infant mortality rate are complex and multifaceted, and we will not attempt in Master Class to address them all. We will, however, address one component: the rising rate of multiple gestations.
Between 1996 and 2002, multiple births in the United States increased more than 22%, from 2.7% to 3.3% of all live births. In 2002, the preterm birth rate among multiple deliveries was approximately 60%, six times higher than the preterm birth rate among singleton births, according to the National Center for Health Statistics. In its preliminary report on births for 2004, the NCHS said that increases in multiple births “have strongly influenced recent upswings” in preterm and low-birth-weight births.
Assisted reproduction plays a role. There is evidence that the percentage of higher-order pregnancies resulting from assisted reproductive technology has been decreasing, but multiple pregnancies with ART remain a problem.
One has to ask whether, with greater care and improved protocols in assisted reproduction, we wouldn't be able to address the continuing effect that infertility treatment has on the rate of multiple pregnancies.
It is a subject that has caught national attention and has been addressed in many quarters. The Society for Assisted Reproductive Technology, an affiliate of the American Society for Reproductive Medicine has examined the issue and made recommendations for improved practice (see sidebar).
My guest professor this month is Dr. Aida Shanti, who is the director of the division of reproductive endocrinology and infertility at the University of Arkansas, Little Rock. She will address these contemporary recommendations and explore how such guidance can potentially have a real impact.
Age-Based Embryo Transfer Guidelines
▸ In patients under the age of 35, no more than two embryos should be transferred in the absence of extraor-dinary circumstances. For patients with the most favorable prognosis, consideration should be given to transferring only a single embryo. Patients having the most favorable prognosis include those who are un-dergoing their first cycle of IVF, have good-quality embryos as judged by morphologic criteria, and have ex-cess of embryos of sufficient quality to warrant cryopreservation. Patients who have had previous success with IVF should also be considered in the most favorable prognostic category.
▸ For patients between 35 and 37 years of age having a more favorable prognosis, no more than two em-bryos should be transferred. All oth-ers in this age group should have no more than three embryos transferred.
▸ For patients between 38 and 40 years of age, no more than four em-bryos should be transferred. For pa-tients in this age group having a more favorable prognosis, considera-tion should be given to transfer of no more than three embryos.
▸ For most patients greater than 40 years of age, no more than five em-bryos should be transferred.
▸ For patients with two or more pre-vious failed IVF cycles and those hav-ing a less favorable prognosis, addi-tional embryos may be transferred according to individual circumstances after appropriate consultation.
▸ In donor egg cycles, the donor's age should determine the appropriate number of embryos to transfer.
Since all oocytes may not fertilize when GIFT is performed, one more oocyte than embryo may be trans-ferred for each prognostic category.
Source: Fertil. Steril. 2004;82:773-4.