“Since frozen embryo transfers occur a significant amount of time after a woman’s ovaries were stimulated with medications, the hormone levels in the body have had time to return to normal, which mimics a more natural conception process,” says William Schoolcraft, M.D., medical director of CCRM. “This process appears to have a positive impact on the health of the baby.”
Researchers have also found that lengthening the time between administering the drugs and pregnancy lowers the chances of a woman’s risk of ovarian hyperstimulation syndrome, a potentially fatal complication that can be triggered by taking certain fertility medications that stimulate egg production.
CCRM data, which was presented at the 2013 American Society for Reproductive Medicine (ASRM) annual meeting in October found that women of advanced maternal age (36-42 years) had a significantly higher live birth rate using frozen embryos in conjunction with comprehensive chromosomal screening (CCS) compared to fresh embryos. Women using frozen embryos for transfer had a live birth rate of 74.5 percent as compared to women using fresh embryos with a live birth rate of 53.7 percent. In addition, we observed only a 2.8 percent miscarriage rate following CCS with a frozen transfer compared to 18.5 percent in the fresh transfer group.