The Graafian follicle is a site of L-ascorbate accumulation.

PURPOSE: Our purpose was to evaluate the L-ascorbate level in human preovulatory follicular fluid and to quantify the blood/follicle gradient for vitamin C. The effect of smoking on the follicular L-ascorbate concentration was studied. The correlations were tested between follicular L-ascorbate and follicle size and oocyte maturity.

METHODS

In 65 women undergoing in vitro fertilization, samples of follicular fluid and blood serum were collected. Biochemical analyses included L-ascorbate determinations by a colorimetric method and cotinine measurements by a radioimmunoassay.

RESULTS

The average follicular fluid:serum ratio for L-ascorbate was 1:68. Ascorbate levels in follicular fluid and serum were significantly correlated. The follicular L-ascorbate level did not correlate with the follicle size and the oocyte maturity grade. Insignificantly lowered follicular L-ascorbate levels were observed in smokers.

CONCLUSIONS

The extracellular compartment of the Graafian follicle is a site of an ascorbate accumulation. Exposure to tobacco smoke does not significantly diminish the intrafollicular pool of L-ascorbate.