Is granulocyte colony-stimulating factor level predictive for human IVF outcome?

BACKGROUND: We investigated granulocyte colony-stimulating factor (G-CSF) in human reproduction. METHODS: From a total sample of 93 patients, we analysed in group 1 (n=82) the level of G-CSF and estradiol (E-2) in serum and follicular fluid (FF) on day of follicular puncture (FP). Furthermore, in response to ovarian stimulation, G-CSF levels in serum were compared between low (n=11), moderate (n=53) and high (n=18) response patients. In group 2 (n=23) serum for G-CSF assessment was collected throughout menstrual cycle until gestation. Group 3 (n=11) patients with endometriosis were assessed for G-CSF in serum and FF on day of FP without further differentiation. RESULTS: G-CSF in FF was higher than in serum (P < 0.01). G-CSF in serum increased from low through moderate to high response (P < 0.001); pregnancy rates were 0, 24.5 and 33.5% respectively. G-CSF in serum increased throughout stimulation, reached a peak with ovulation induction (P=0.01) and decreased until embryo transfer (P=0.001). G-CSF level only in pregnant patients (n=11) increased from embryo transfer to implantation to gestation (P=0.005). In endometriosis patients G-CSF in serum and FF was lower than in non-endometriosis patients (P <= 0.03) and corresponded with low response patients. CONCLUSIONS: G-CSF is involved in follicle development and may be a predictor of IVF outcome.