human eggs

Number of eggs

A woman has the maximum number of potential eggs (primary oocytes) while still a fetus, more than 7 million. By birth the number has fallen to 1 or 2 million, and by puberty to about 300,000. Only 300 to 400 reach maturity.

Size of eggs

A human oocyte is about 100 micrometers in diameter, which is large for a cell. If it is not fertilized within a day of its ejection from the ovary, it dies.