A study published in the Journal of the American Medical Association examined outcome of egg donor cycles in the U. S. But what was their definition of a good outcome?
The authors examined trends and outcomes in donor egg cycles from 2000 to 2010 and analyzed predictors of good perinatal outcomes among in vitro fertilization cycles using fresh (non-cryopreserved) embryos derived from donor eggs. The data come from the Centers for Disease Control and Prevention’s National ART Surveillance System. Good perinatal outcome was
defined as a singleton live-born infant delivered at 37 weeks of gestation or later and weighing 2,500 g or more.
Does this mean that twins born at term and healthy is not a good outcome? How about a singleton slightly below 2500 grams, but otherwise healthy and who develops normally? I think that couples who have struggled for years to conceive and finally move to egg donation would consider these two scenarios as a good outcome.
Mandatory reporting is required in the United States so data from 443 clinics (93% of all U.S. fertility centers) were available. The annual number of donor egg cycles significantly increased, from 10,801to 18,306. Among all donor egg cycles, an increasing trend was observed from 2000 to 2010 in the proportion of cycles using frozen embryos from 26.7% to 40.3% and elective single-embryo transfers 0.8% to 14.5%. Good perinatal outcome increased from 18.5% to 24.4%.
Donor cycles performed in 2010 using fresh embryos (9,865), 27.5% resulted in good perinatal outcome. Transfer of an embryo at day 5 and elective single-embryo transfers were positively associated with good perinatal outcome. Donor cycles resulted in twins more often (37%) than autologous cycles.
Tubal factor infertility or uterine factor infertility and non-Hispanic black recipient race or ethnicity were associated with decreased odds of good perinatal outcome. Recipient age was not associated with likelihood of good perinatal outcome.
The greater use of single embryo transfer is a good trend and, of course, a single full term healthy baby is the most desired result. But if this study is quoted giving only a 24.4% for frozen and 27.5% for a fresh transfer “good outcome rate,” it might discourage some couples from moving to egg donation when that is their only way of having a biological child that is genetically related to at least one of them.