The cervix is the lower portion of the uterus -the organ where the egg , once fertilized, attaches and develops to maturity. Extending from either side of the top of the uterus are the fallopian tubes . The tubes connect to the ovaries , two small organs that produce eggs and the female sex hormone, estrogen . At the time of birth, a woman's ovaries contain approximately 400,000 eggs. Controlled by the monthly fluctuations in hormone levels, these eggs are qued one by one in a monthly cycle known as menstruation.
Menstruation starts when a female has reached sexual maturity.
At this time, eggs begin reaching maturity at a typical rate of one ovum, or egg, per monthly cycle. At mid-cycle, called ovulation , a single egg is typically released from the ovaries. The egg travels down the fallopian tube toward the uterus. It is at this brief time, when the egg is in the fallopian tube, that conditions are optimal for fertilization by the male's sperm to result in pregnancy. A. Vagina - the female organ of sexual intercourse and birth canal.