A human being undergoes physical and emotional changes from childhood to adulthood. The changes are gradual and occur at different ages and speed in different people. These stages may be identified in a simplified way as childhood, adolescence, adulthood and old age. In this guide we are concerned with the adolescent stage of human development, which is characterized by dynamic changes in physical and behavioral traits. In spite of their different appearances, the s£xual organs of men and women arise from the same structures and fulfill similar functions. Each person has a pair of gonads: ovaries are female gonads; testes are the male gonads. The gonads produce germ cells and s£x hormones. The female germ cells are ova (egg) and the male germ cells are sperm. Ova and sperm are the basic units of reproduction; their union can lead to the creation of a new life. Hormones and reproductive life cycle There are many powerful cultural and personal factors that shape the expression of ones’ s£xuality. But biology also plays a role, particularly through the action of hormones, chemical messengers that are secreted directly into the bloodstream by endocrine glands. The s£x hormones produced by the ovaries and testes greatly influence the development and functions of the reproductive system throughout life. The s£x hormones made by the testes are called androgens, the most important if which is testosterone. The female s£x hormones, produced by the ovaries, belong to two groups: estrogens and progestins, the most important of which is progesterone. The cortex of the adrenal glands (located at the top of the kidneys) also produces androgens in both s£xes. The hormones produced by the testes, the ovaries, and the adrenal glands are regulated by the hormones of the pituitary gland, located at the base of the brain. This gland in turn is controlled by hormones produced by the hypothalamus in the brain.S£x hormones exert their primary developmental influences first in the embryo stage, where they control the development of a male or female reproductive system, and later during the individual’s adolescence.
Female reproductive organs The female reproductive organs are those parts of the body that are directly involved in s£xual activity, pregnancy, and childbearing. They comprise of external parts, internal parts and the breasts. External reproductive organs (Vulva) The vulva is the area surrounding the opening of the vagina, which can be seen from the outside. They consist of the clitoris, vagina opening, labia majora and labia minora. The outer folds of skin, called the labia majora, are thick and covered with hair. The two inner folds of skin, called labia minora, are much thinner. They cover and protect the vaginal opening. These inner folds form a hood around the clitoris. The clitoris is a small, sensitive organ above the vagina that responds to stimulation and makes s£xual intercourse pleasurable for women. Inside the vaginal opening is a pair of glands that produces a thin fluid, which moistens the vagina, especially during s£xual intercourse.
Internal reproductive organs These are organs of the female body that are located inside the lower part of the abdomen,called the pelvis, and are protected by bones and muscles. They consistof the vagina, the uterus (womb), two ovaries, and two fallopian tubes. The vagina, covered at the opening by a thinmembrane called the hymen, is the largest ofthe three openings in the genital area. It ismade up of soft folds of skin and is about 7 cmdeep and 3–4 cm wide. The other twoopenings are the anus (below the vagina) andthe urethra (above the vagina).The walls of the vagina produce a fluid ordischarge that serves to keep the region clean.At different times of each month the amount ofdischarge increases - particularly at times of s£xual excitement - and it is important to notethat this is completely normal. However, if that discharge changes its usual normal colour, causes itching or takes on abad smell, it may indicate an infection. So it isimportant to pay attention to the discharge and how it changes during the monthly cycle.During childbirth the baby leaves the womb and enters the world through the vagina. This is why it is sometimes called a “birth canal”. The walls of the vagina are elastic and can stretchto allow the passage of the baby’s head and body. The uterus (womb) is the muscular organ inside a woman’s body where the baby grows. The cervix is sometimes called the opening/neck/mouth of the womb. It connects the uterus to the vagina and normally has a very small opening. This protects the uterus from infections. During pregnancy this opening stays small so that the baby stays inside the womb. Duringlabour the cervix opens up (dilates) so that the baby can be born. The ovaries are two small egg-shaped organs on either side of the uterus that store eggsand release one mature egg each month during a girl/ woman’s reproductive years of life.The fallopian tubes are two hollow-like structures that connect the ovaries to the uterus oneither side. The tubes are 10–12 cm. long. After the mature egg has been released from oneof the ovaries, it travels down the fallopian tubes to the uterus.
The breast The main external feature of the breast is the nipple and the dark skin around it, called the areola. A hormone called estrogen causes the tissues and glands in the breasts to grow sothat when a woman becomes pregnant, she is able to produce and store milk. Often, both breasts swell slightly during the menstrual period. In many women, one breast is larger thanthe other. Hormones and their functions. There are many hormones involved in the physical development and the normal reproductiveand s£xual functioning of a girl or woman. The major ones are oestrogen, progesterone,follicle-stimulating hormone and luteinizing hormone. Below is a brief description and functionof each hormone.The follicle-stimulating hormone (FSH) is a hormone produced by the pituitary gland found inthe brain. FSH stimulates or activates the ovarian follicles (immature eggs) to grow andrelease estrogen and progesterone hormones.The luteinizing hormone (LH) that is produced from the pituitary gland makes the immatureeggs grow faster of which only one matures ready for fertilization. It is then released into thefallopian tube. The ovaries produce estrogen that supports the growth of the uterine lining in preparation forimplantation of the fertilized egg. Estrogen also makes cervical mucus thin, clear andstretchy to assist entry and nourishment of the sperm. Progesterone, which is produced by the ovaries, makes the uterine lining and wall thickerand richer in blood supply. The uterine wall becomes rich in nutrients ready for implantation.Progesterone enables the cervical mucus to become thicker and stickier, preventing germsfrom entering the uterus and blocking the passage of sperm.