Female sex organs and reproductive system

The ovaries produce eggs (ova). There are 2 of them, deep in the pelvis, one on each side of the uterus (womb), close to the ends of the fallopian tubes. The ovaries at birth contain all the eggs they will ever have.

Each month during ovulation, one egg matures and is released from an ovary. The egg travels down the fallopian tube toward the uterus. If the egg is fertilized by a sperm (from the male reproductive system) in the fallopian tube, the fertilized egg attaches itself (implants) to the lining of the uterus (called the endometrium). Once implanted, the fertilized egg grows in the uterus, becoming an embryo and then a fetus.

The ovaries also make hormones. The female sex hormones are estrogen and progesterone. The ovaries are the main source of these hormones. When puberty begins, the pituitary gland in the brain signals the ovaries by releasing the follicle-stimulating hormone (FSH) and the luteinizing hormone (LH). The ovaries then begin to make and release the estrogen and progesterone, which are necessary for reproduction.

Estrogen is the main female sex hormone. It controls:

• the development of breasts and reproductive organs
• the growth of body hair
• the growth of the lining of the uterus during the menstrual cycle
• keeping the sexual organs healthy

Progesterone prepares the endometrium for a fertilized egg to implant. It then helps the endometrium nourish an embryo and maintain a pregnancy. Progesterone also regulates the menstrual cycle.

With each menstrual cycle, your supply of eggs lessens. When most of the eggs are gone, menopause begins. During menopause, the menstrual cycles stop, the ovaries stop making estrogen and progesterone, and you can no longer become pregnant.

The uterus, or womb, is the part of the female reproductive system where a baby grows. It is above the vagina, between the bladder and rectum. It is about 7 cm long and 5 cm across at the widest point. The uterus is held in place within the pelvis by several ligaments.

Every month, except during pregnancy or after menopause, the lining of the uterus grows and thickens in preparation for pregnancy.

During pregnancy, the uterus holds and nourishes the baby. The uterus contracts to push the baby out of the body during birth.

If you are not pregnant, every month or so the lining is shed through the cervix into the vagina and out of the body. This is called menstruation. This process of monthly bleeding continues until menopause.

The cervix is the lower, narrow part of the uterus. The cervix connects the main body of the uterus to the vagina.

Part of the lining of the cervix contains glands that make and release mucus. For most of the menstrual cycle and during pregnancy, the mucus is thick and stops sperm from entering the uterus. The thick mucus also helps to protect the uterus and the upper female reproductive organs from harmful bacteria.

During ovulation, the mucus changes and becomes thinner. The thinner mucus allows sperm to pass through the cervix into the uterus.

During childbirth, the cervix widens (dilates), allowing the baby to pass through the birth canal.

The vagina is a passageway that connects the cervix, which is the opening of the uterus, to the outside of the body. It is also known as the birth canal. The vagina has nerves, blood and lymph vessels. Glands of the cervix and glands near the opening of the vagina secrete mucus to keep the mucosa moist.

The vaginal walls are usually collapsed and touch each other. The walls have many folds, which let the vagina expand during sex or the birth of a baby.

The vagina has 3 main functions:

• It provides a passageway for blood and mucosal tissue from the uterus during your monthly period.
• It receives the penis during sexual intercourse and holds the sperm until they pass into the uterus.  
• It provides a passageway for childbirth.

The vulva is made up of several organs.

The labia majora are 2 outer skin folds that look like lips. They cover and protect the other external organs. During sexual stimulation, the labia majora may become swollen with blood.

The labia minora are 2 smaller skin folds just inside the labia majora. They cover the vaginal and urethral openings.

The clitoris is a small organ in front of the labia minora. It has many nerve endings. When you are sexually stimulated, the clitoris becomes swollen and erect with blood.

The urethral opening is the opening of the urethra. The urethra is the tube that connects to the bladder and allows urine (pee) to leave the body. The urethral opening is found just under the clitoris.

The vaginal opening is the opening to the vagina. The vagina is the muscular canal leading to the cervix.

The Bartholin glands are found just inside the vulva. They produce a thick fluid, which acts as a lubricant during sexual intercourse.

The perineum is the space between the vulva and the anus.

The anus is the opening at the lower end of the rectum (the last section of the large intestine) where waste (poop) is passed from the body.

When you become sexually excited, your vulva becomes sensitive to stimulation and your nervous system sends signals of pleasure to your brain. These may produce an orgasm. During an orgasm, the muscles around the sex organs contract. There are different sources of pleasure for everyone. You may have an orgasm through intercourse but you may also have an orgasm by touching the sex organs, such as the clitoris and inner lips.