In vivo maturation of oocytes by extending the interval between human chorionic gonadotropin administration and oocyte retrieval.
OBJECTIVE
To find whether the percentage of mature oocytes can be increased in the following ICSI cycle, in a selected group of patients with >or=47% immature oocytes, with the prolongation of hCG-to-oocyte retrieval interval.


METHODS
Randomized study.


METHODS
In vitro fertilization unit in a medical center in Israel.


METHODS
From January 2003 to June 2005, in 72 of 2,650 intracytoplasmic sperm injection cycles (2.8%), >or=47% of the total aspirated oocytes were immature (group A). In the following treatment cycle, with similar controlled ovarian hyperstimulation, hCG was planned to be injected in the same interval (group B) as well as 3-4 hours earlier (group C). In fact, the hCG-to-oocyte retrieval interval in group C was statistically significantly longer (38.6 +/- 1.2 hours) compared with that in group B (35.3 +/- 0.7 hours).


METHODS
The clinical characteristics of the patients, ovarian stimulation, hormonal profile, and the intracytoplasmic sperm injection outcome of the various groups were assessed.


METHODS
The number and maturity of the aspirated oocytes.


RESULTS
The mean number of ampules needed for stimulation, treatment duration, serum E(2), and P level on the hCG day were similar in the various groups. Escaped ovulation did not occur in any of the patients. A larger number of aspirated oocytes, a statistically significantly larger percentage of mature oocytes (72%), and a statistically significantly lower percentage of metaphase I (12%), germinal vesicle (18%), and degenerated oocytes (8%) were found in group C compared with group A (50%; 16%, 21%, and 13%, respectively). Similar morphological distribution of the aspirated oocytes was observed among groups B and C. Clinical implantation and pregnancy rates were higher in group C compared with group B.


CONCLUSIONS
In a selected group of patients with >or=47% immature oocytes per retrieval, a larger cohort of mature oocytes can be recruited by extending the hCG- to-oocyte retrieval interval in a subsequent cycle. This improved outcome directly affects the quality of embryos available for transfer and thus increases pregnancy rate.
Raziel
Arieh
A
Infertility and IVF Unit, Assaf Harofeh Medical Center, Tel Aviv University, Zerifin, Israel. araziel@012.net.il
Schachter
Morey
M
Strassburger
Deborah
D
Kasterstein
Esti
E
Ron-El
Raphael
R
Friedler
Shevach
S
D000328:Adult; D018929:Cell Culture Techniques / Q000379:methods*; D049109:Cell Proliferation / Q000187:drug effects; D002469:Cell Separation; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000008:administration & dosage*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D007247:Infertility, Female / Q000628:therapy*; D009865:Oocytes / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development*; D010062:Ovulation Induction / Q000379:methods*; D013997:Time Factors
D006063:Chorionic Gonadotropin