Light microscopy of the fetal ovary showing primordial follicles comprised of squamous follicle cells enclosing a central oocyte. The supporting tissue has blood vessels and connective tissue cells. In humans there may be up to 5 million primordial follicles in the pair of fetal ovaries. Most of the follicles degenerate before birth, leaving on average several hundred thousand. From the postnatal ovarian reserve only around 400 follicles will reach maturity and ovulate an oocyte. Magnification x540 when printed at 10 cm.