How the Body Works Female Reproductive Organs The female sex organs lie in the lower abdomen, where they are protected by the bony pelvis. At puberty, the two almond-shaped ovaries begin to produce the female hormones, estrogen and progesterone, and the sex cells, or ova. Each month, the ovary releases an ovum into the funnel-shaped opening of a Fallopian tube. If coitus occurs it is here that the ovum may be fertilized. Each Fallopian tube is approximately four inches long and is lined with ciliated cells. The two Fallopian tubes lead into the womb, or uterus, a three-inch-long pear-shaped organ lined with the endometrium, which is shed and built up again each month. It is in this endometrium that the fertilized egg implants and grows during pregnancy. The neck of the womb, or cervix joins the uterus with the muscular vagina, which leads to the external genitalia, or vulva. The female urinary system, unlike that of the male, is separate from the reproductive system. The bladder empties into the urethra, which opens just in front of the vagina.