REDUCED IN-VITRO FERTILIZATION OF HUMAN OOCYTES CORRELATES WITH RAISED CIRCULATING FSH-LEVELS DURING OVARIAN STIMULATION IN NORMOGONADOTROPIC WOMEN DOWN-REGULATED WITH GNRH-ANALOGS
Cy. Andersen et al., REDUCED IN-VITRO FERTILIZATION OF HUMAN OOCYTES CORRELATES WITH RAISED CIRCULATING FSH-LEVELS DURING OVARIAN STIMULATION IN NORMOGONADOTROPIC WOMEN DOWN-REGULATED WITH GNRH-ANALOGS, Journal of assisted reproduction and genetics, 14(10), 1997, pp. 581-588
Purpose: The possible effects of circulating FSH levels as used during
IVF treatment on oocyte maturation and subsequent preembryo developme
nt were evaluated. Methods: Serum levels of FSH and LH on days 1 and 8
of ovarian stimulation and on the day of oocyte retrieval (OR) were c
orrelated with subsequent preembryo development in vitro. After pituit
ary downregulation, 244 normogonado-tropic women followed a Fred proto
col for the first 7 days of stimulation. Results: The average FSH conc
entration on day 8 of stimulation was 11.5 IU/L and exceeded the expec
ted midcycle surge of FSH by more than 25%. In contrast, levels of LH
were below an average of 2 IU/L throughout the stimulation period. The
concentration of FSH on day 8 and oil the day of OR Showed a signific
ant inverse correlation with cleavage rate, whereas levels of LH, age,
and body mass index showed no such correlation. Conclusions: Supraphy
siologic levels of FSH seems to affect oocyte maturation negatively. P
remature resumption of meiosis, leading to retrieval of postmature ooc
ytes with a reduced developmental potential, is suggested as the under
lying mechanism.