Single Versus Double Frozen Embryo Transfer in PCOS Patients

Polycystic ovarian syndrome (PCOS) is condition characterized by being complex, familial and polygenetic metabolic condition with heterogeneous involvement of several genes in the hypothalamic-pituitary-gonadal axis. PCOS is the most incident endocrine-metabolic syndrome that is characterized by hyperandrogenemia, menstrual irregularities, and/or small cysts in one or both ovaries and could be considered as the main cause of female infertility.

Assisted reproductive technologies (ART) were defined by the American Center for Disease Control as any fertility-related treatments where eggs or embryos are manipulated. In vitro fertilization involves the transfer of fresh embryos, however, the freeze-all strategy that entails cryopreservation of all embryos to be transferred subsequently in un-stimulated cycle to guard against the negative effects of controlled ovarian stimulation on the endometrium and to minimize the risk of ovarian hyper-stimulation syndrome. Intracytroplasmatic sperm injection (ICSI) is a common procedure used to improve reproductive results, even among couples without male factor infertility.

However, there are several points of controversy in the fields of ART traditionally, multiple embryo transfer strategy was used to increase the chance for getting a baby, however, multiple pregnancy is a common complication for this strategy with subsequent adverse fetal, maternal and neonatal outcomes. Also, the developmental stage of embryos at time of transfer; cleavage versus blastocyst was a matter of debit, but giving the chance for in-vitro maturation to the stage of blastocyst increased the possibility of getting good quality embryo to be transferred. However, the exaggeration of prolongation of the in-vitro duration appeared as a trend, but recent studies found no advantages for transfer of D7 or D6 blastocyst over D5 blastocyst transfer (BT).