A 38 h interval between hCG priming and oocyte retrieval increases in vivo and in vitro oocyte maturation rate in programmed IVM cycles.
BACKGROUND
Our aim was to evaluate whether extending the interval between human chorionic gonadotrophin (hCG) priming and immature oocyte retrieval increases the oocyte maturation rate following in vitro maturation (IVM).


METHODS
This study was performed retrospectively. IVM was performed on 113 polycystic ovary syndrome patients (n = 120 cycles). Oocyte collection was performed either 35 h (Group 1; n = 76) or 38 h (Group 2; n = 44) after 10,000 IU of hCG priming. Following oocyte retrieval, oocyte maturity was assessed and the remaining immature oocytes were cultured in IVM medium up to Day 2.


RESULTS
The number of in vivo matured oocytes collected was significantly higher in Group 2 (13.6%, 114/840 versus 7.3%, 96/1312 in Group 1) (P < 0.01); the oocyte maturation rate after Day 1 was significantly higher (P < 0.01) in Group 2 (46.3 versus 36.0% in Group 1); and clinical pregnancy (40.9 versus 25%) and implantation rates (15.6 versus 9.6%) were better in Group 2 than those in Group 1.


CONCLUSIONS
The results suggest that extending the period of hCG priming time from 35 to 38 h for immature oocyte retrieval promotes oocyte maturation in vivo and increases the IVM rate of immature oocytes. Therefore, oocyte retrieval after 38 h of hCG priming may improve subsequent pregnancy outcome in cycles programmed for IVM treatment.
McGill Reproductive Center, Department of Obstetrics and Gynecology, Royal Victoria Hospital, McGill University, Montreal, QC, Canada H3A 1A1. weon-young.son@muhc.mcgill.ca
Weon-Young
WY
Son
Jin-Tae
JT
Chung
Ri-Cheng
RC
Chian
Belen
B
Herrero
Ezgi
E
Demirtas
Shai
S
Elizur
Yariv
Y
Gidoni
Camille
C
Sylvestre
Nicola
N
Dean
Seang Lin
SL
Tan
D006063:Chorionic Gonadotropin / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D010064:Embryo Implantation; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007247:Infertility, Female / Q000209:etiology; D009865:Oocytes / Q000254:growth & development*; D011085:Polycystic Ovary Syndrome / Q000150:complications; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies; D013997:Time Factors
D006063:Chorionic Gonadotropin