Puberty and Adolescence

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Puberty in girls

Puberty usually occurs in girls between 9 and 16 years old. The start of menstrual periods (menarche) is one of the most visible signs that a girl is entering puberty. Before having the first menstrual period, the pubescent girl will normally experience:

• rapid growth, especially an increase in height
• breast enlargement
• pubic, armpit, and leg hair growth
• clear or whitish vaginal secretions
• increased hip width

The ovaries increase their production of estrogen and other hormones. This begins the monthly menstrual cycle. Having menstrual periods is only one part of this cycle. Girls are born with a place for babies to grow (the uterus). Next to the uterus are two small glands (the ovaries). The ovaries produce the female hormones and begin to release eggs, which have been stored in the ovaries since birth.

Every month (approximately), an ovary releases one egg. This egg travels along the Fallopian tube, which connects the ovary to the uterus. In about 3 or 4 days the ovum reaches the uterus. During this time, the lining of the uterus (endometrium) begins to thicken by filling with blood and fluid. This happens so that if the ovum is fertilized, it can grow in this thickened lining to produce a baby.

The ovum can become fertilized if unprotected sexual intercourse occurs during this "fertile" time. When a sperm cell (from the man) and an egg (from the woman) join, a pregnancy occurs.

If the egg is not fertilized, it dissolves and the endometrium drains off, out of the uterus through the vagina, causing a menstrual period. In between the menstrual periods, there may be a clear or whitish vaginal discharge. This is normal.

Menstrual cycles occur over about one month (28 to 32 days). At first, the menstrual periods typically are irregular. The girl may go two months between periods, or may have 2 periods in one month. Over time, these will become more regular. The girl may want to keep track of when she has a menstrual period, and how long the period lasts, on a calendar. This can help her to see what her individual pattern is, and can help her predict when she will have the next menstrual period.

Generally, the different phases of the menstrual cycle are not uncomfortable and the majority of girls will not notice any problems. Cramping, when present, is usually mild. Severe menstrual cramping should be evaluated by a physician. There may, however, be other cyclic changes -- for example, just before or during a menstrual period the girl may feel "moody" or emotional, and may feel puffy or swollen. PMS (premenstrual syndrome) may begin to develop, especially as the girl gets older.

In girls, maturation is usually complete by age 17. Subsequently, any increases in height beyond this age are uncommon. Although full physical maturity has been reached educational and emotional maturity remain ongoing processes. It is important to remember that fertility (often present as early as 12 years of age) precedes emotional maturity and pregnancy can, and often does, occur before an adolescent is equipped for parenthood.