IVF protocol
Doctors chose different IVF protocols based on the patient’s age and
ovarian reserve. The GnRH agonist and GnRH antagonist protocols have
been the main protocol in our center. Controlled ovarian
hyperstimulation, oocyte retrieval, embryo transfer, and endometrial
preparation for frozen-thawed embryo transfer (FET) were performed as
previously described [6,7]. Briefly, for the GnRH agonist, patients
used down-regulation from the mid-luteal phase of the previous cycle,
recombinant FSH was started at 150-225IU/day when the pituitary had
reached desensitization. For the GnRH antagonist protocol, recombinant
FSH was initiated on day 2 of the cycle. GnRH antagonist was started
when the dominant follicle reached 12-14mm at 250mg/d. When two or more
follicles reached 18mm, hCG was administrated at a dose of 4,000 to
10,000. Oocyte retrieval was carried out 34-36 h following hCG trigger.
Conventional IVF or intracytoplasmic sperm injection (ICSI) was
performed according to the male partner’s semen quality.