Background: A woman's fertility is remarkably reduced with increasing age. Reproductive age can be assessed by a number of ovarian reserve tests. There are very few studies addressing the effects of age on these markers in fertile women, especially in Asia.
Methods: On the second to fourth day of the menstrual period, fertile Chinese women with regular monthly cycles and no history of ovarian surgery underwent a transvaginal scan with colour Doppler to determine ovarian volume, total antral follicle count (AFC) and mean peak systolic velocity (PSV) of ovarian stromal blood flow, and their serum FSH and inhibin B levels were checked.
Results: Out of 145 women scanned, 119 were included in the final analysis. AFC is the only ovarian reserve marker that was significantly different among four age groups (</=20, 21-30, 31-40 and >40 years). AFC had the best correlation with the age of the women, followed by FSH level and ovarian volume. The decline of AFC with age was 3.8% per year (95% confidence interval 2.7-4.9%) in the conventional linear regression model, which was not improved by the biphasic linear regression model.
Conclusion: Of the parameters tested, AFC showed the best correlation with women's age and declined linearly at a rate of 3.8% per year.