In summary, in this study we have shown that rapamycin treatment can prevent the complete loss of primordial follicles that would otherwise occur in mice with an oocyte-specific deletion of Pten. The implication of these results is that rapamycin may be clinically useful in maintaining at least a portion of the primordial follicle pool in the ovaries of women who are otherwise at risk for POF. The gene discussed is PTEN; the disease is premature menopause.