This is accomplished using medications called GnRH agonists . The recipient's uterine lining is prepared for embryo transfer by administering increasing doses of the hormones estrogen and then progesterone . Development of the uterine lining is monitored via blood tests and ultrasound examination. Donor eggs are retrieved, and then fertilized with sperm from the male partner. Generally, only two or three embryos are then transferred to the prepared uterus of the recipient.
Hormone treatment continues into the first trimester if a pregnancy is established.
As with traditional IVF , excess healthy embryos can be frozen for transfer at a later time. Pregnancy Pregnancy rates in donor egg cycles tend to be higher than in traditional IVF cycles. The higher success rates are believed to result from the younger age of the egg donors. Higher success rates mean fewer embryos need be transferred to the recipient. The age of the recipient doesn't affect the success of the procedure.