Adolescents in any country who become pregnant face severe health risks whether they are married or not. Adolescents are not fully physically developed: at menarche a young woman's pelvis has not finished growing. Therefore, pregnancy and birth at a young age hold pose serious risks for both mother and child. Mothers under 20 suffer more complications in pregnancy and delivery than women who bear children at age 20 or later. Deaths from anaemia, eclampsia and obstructed labour are more common in young mothers. If the mother is small as well as young, she is likely to give birth to a small, weak baby whose chances of survival are equally small. The infants of adolescent mothers have a higher incidence of low birth weight, prematurity, stillbirth, and perinatal mortality. In addition, young women, particularly if they are unmarried, often have less access to ante-natal care so that potential problems are not noticed or treated.
In some societies unmarried adolescent girls who give birth are social outcasts, while in other societies - where having a child also may represent a rite of passage into adulthood - young girls are pressured into pregnancies in order to prove their fertility, although they may not yet be socially or psychologically prepared for the responsibilities of parenthood.
A teenage pregnancy can have dire consequences for the economic future of the teenager and her child. In many societies, pregnant students are forced to leave school. Some therefore secretly seek abortions, with all the attendant risks, in order to avoid expulsion. Even if pregnant students are allowed to continue their schooling, few succeed in completing their education. This, in turn, leads to employment in low paying positions, unemployment or reliance on public support. As a result, mother and child are more likely to suffer from poor nutrition and health care.
Although the extent of pregnancy among young women is not know with precision, it is believed that in many countries, industrialized and developing, each year between 5 and 10 percent of all 15 to 19 year olds become pregnant; in some parts of Africa the figure is over 20%. Worldwide, 15 million teenage women give birth each year, accounting for up to one-fifth of all births. The vast majority of these births are in developing countries. Also worldwide, pregnancy related complications are the main cause of death among 15 to 19 year old women.
According to data from the World Fertility Survey, over half of all women aged 25-29 had their first birth before the age of 20 in: Benin, Ghana, Kenya, Senegal, Jordan, Sudan, Yemen, Indonesia, Bangladesh, Pakistan, Dominican Republic, and Jamaica. In the Caribbean, almost 60% of first babies are born to women under 19, and half of these are born to mothers under 17 years of age. In Indonesia, 41% of women have their first baby before they reach 17 years of age. The Russian teenage pregnancy rate is very high and, despite the high rate of abortions, 5.5% of adolescents actually give birth. In Bangladesh, where girls as young as 12 are married, one-fifth have had a baby before they are 15, and 80% before 20.
In the USA, more than a million teenage girls become pregnant every year, about 30,000 of them under 15. A 1993 study of American teenagers showed that in one year an estimated 10 million will engage in sexual intercourse resulting in 1 million pregnancies, 406,000 abortions, 134,000 miscarriages and 490,000 births, of which about 64% (313,000) will be to unmarried mothers. A 1990 study showed that 32% of 14 and 15 year old American girls had already had sexual intercourse, while 17% of 17 to 18 year olds had had four or more partners.
In the UK, slightly more than half the local health authorities have special contraceptive services for young people.