SANTA BARBARA, CALIF. – Comprehensive chromosomal screening followed by single-embryo transfer resulted in similar delivery rates but significantly fewer multiple gestations, and better maternal and fetal outcomes, compared with conventional transfer of two embryos without screening, a prospective randomized trial of 175 patients found.
As a result, overall costs per delivery are so much lower after comprehensive chromosomal screening and single-embryo transfer (eSET) that these techniques may prove to be the most cost-effective development ever in the field of IVF, Dr. Richard T. Scott Jr. said at the UCLA annual in vitro fertilization and embryo transfer update 2013.
An intent-to-treat analysis by Dr. Scott and his associates found that 61% of 89 patients in the study who received single-euploid blastocysts gave birth, compared with 65% of 86 patients who received two embryos without screening,
Dr. Richard T. Scott
All single-euploid blastocysts produced singletons. "We were fortunate enough to have no monozygotic twins, at least not yet," he said. In the double-embryo transfer group (DET), 48% developed multiple gestations, including one set of triplets due to monozygotic twins from one of the embryos.
In general, approximately 99% of long-term sequelae from in vitro fertilization (IVF) relates to multiple gestations, he noted. Comprehensive chromosomal screening plus eSET may be a way to maintain high delivery rates without multiple gestations, said Dr. Scott, professor of obstetrics, gynecology and reproductive services and director of the division reproductive endocrinology at Robert Wood Johnson Medical School, New Brunswick, N.J.
Clinical miscarriages were greatly reduced in the eSET group (12%) compared with the DET group (20%). For each single gestational sac, the difference was even more pronounced, with a 31% clinical miscarriage rate for DET.* Five women in the eSET group required dilation and curettage for clinical miscarriage, none due to aneuploidy, as did eight in the DET group, two with documented aneuploidy. Two nonviable second-trimester twins were delivered in the DET group.
The rate of preterm deliveries in the eSET group (8.9%) was similar to the U.S. average for the general population of pregnancies in women who did not receive IVF services (8%), both of which were significantly lower than the 28% preterm birth rate in the DET group.
Admissions to the neonatal intensive care unit affected 11% in the eSET group and 26% after DET, but the difference did not reach statistical significance. Stays in the neonatal ICU were shorter after eSET than after DET, with the exception of one infant who underwent elective premature delivery because of acute maternal health problems.
"The most compelling data" from the study showed significantly better obstetrical outcomes from comprehensive chromosomal screening and eSET, Dr. Scott said. Mean birth weights were 3,408 g in the eSET group and 2,745 g in the DET group. Rates of low birth weight (less than 2,500 g) were 4% after eSET and 32% after DET. No infants in the eSET group had a very low birth weight (less than 1,500 g), compared with 7% of the DET group, although this difference did not reach statistical significance.
"These are dramatic, dramatic differences" just from reducing double-embryo transfers to single embryos with comprehensive chromosomal screening, Dr. Scott said. "This is not putting three and four [embryos] back; this is not Octomom. We’re talking about two-embryo transfers in the other group."
The study has been submitted to the journal Fertility and Sterility for publication, said Dr. Scott, who is the clinical and scientific director of Reproductive Medicine Associates of New Jersey, Morristown, the clinical center that serves the medical school’s division of reproductive endocrinology.
The findings should be applicable to the general IVF population, not just selected patients, he added. A separate analysis of 210 single-euploid blastocyst transfers and 1,435 untested double-blastocyst transfers at his institution found similar ongoing pregnancy rates (68% each) but a nearly threefold higher risk for preterm delivery after DET (30%) compared with eSET (11%), which was statistically significant.
Dr. Scott and his associates also analyzed actual cost data for comprehensive chromosomal screening and eSET, which averaged less than $40,000 per live-born delivery, compared with more than $70,000 per delivery with conventional IVF treatment, both national and regional averages showed. The costs included sometimes multiple cycles of IVF, the costs of comprehensive chromosomal screening and medications, and the costs for delivery and subsequent hospital stays through 28 days of life, he said.
The savings come from fewer IVF cycles with comprehensive chromosomal screening and eSET, better outcomes, and reduced obstetric and pediatric costs that, combined, "could more than pay for all of their infertility care," Dr. Scott said.