Few unmarried young couples use contraception the first time that they have sexual intercourse. Among women ages 15 to 24 surveyed in Latin America and the Caribbean, the levels of contraceptive use at first intercourse ranged from 4% in Quito to 43% in Jamaica. For men 15 to 24, the percentages using contraception at first intercourse ranged from 14% in Quito and Guayaquil to 31% in Mexico City. Use at first intercourse increases with age (338).

Studies in the US and other countries have found that women delay about one year on average between starting sexual activity and first using modern contraceptives (17, 108, 245). Thus premarital sexual activity often results in unintended pregnancy.In Mexico City nearly two-thirds of women ages 18 to 19 with premarital sexual experience reported that they had been pregnant at least once (337). In a Zimbabwe study 46% of premaritally sexually active women ages 11 to 19 had been pregnant (62). Many unplanned pregnancies occur within a year after first sexual intercourse (108, 562). For example, of 200 16-year-olds delivering at Harare Maternity Hospital, Zimbabwe, over one-half had become pregnant within just three months of starting sexual activity (304).

Why don't more young people use contraception if they are having sex? The most common reason that both young men and women give for not using contraception is that they did not expect to have intercourse. The second most common reason is that they did not know about contraception (255, 337, 338). Other reasons for low levels of contraceptive use, however, may be more subtle and even more difficult to address.

Lack of information. Young people often know little or have incorrect information about fertility and contraception. Young men are more likely than women to mention lack of knowledge and are much more likely to say that it is their partner's responsibility to avoid pregnancy (39, 49, 337). Even when young people can name contraceptives, they often do not know where to get them or how to use them (13, 118). Like many adults, many young people have negative attitudes about contraceptives, have heard false rumors, and have received misleading information about contraception. For example, students in Kenya and Nigeria had heard about contraceptives but incorrectly cited dangerous side effects (39).

Lack of access. Even when young adults know about contraceptives, few use them (13, 14,294). Often this may be because it is more difficult for young adults to obtain contraceptives than it is for older, married couples. Young adults are generally healthy and are not accustomed to visiting health care providers or clinics. They do not know where to go or what to expect. Many are unable to pay for services or for transportation to clinics. Often laws prohibit or limit providing contraceptives, services, or even information to young people (113, 371). Even where access is not restricted by law, some family planning services have policies or prejudices against serving unmarried people. Rude or judgmental staff deter some young people from seeking contraceptives. For example, in a South African study young field workers posing as clients reported that personnel at some clinics resisted their requests for condoms and often provided no instructions on condom use (5).

Lack of decision-making and lack of power. Even when young people have information about contraceptives and access to services, many contextual factors affect their contraceptive practices. The extent of communication between partners, attitudes about social and sexual roles, and the taboo nature of their sexual activity all influence young adults' sexual decision-making (51, 359). For example, in many cultures sex-related issues are rarely discussed, even between spouses. Young unmarried people may be even less likely to discuss contraception. Many young adults see contracep- tion as something only for married adults who want to space their children (430). Some men and some women themselves may disapprove of contraception because they believe it encourages women to promiscuity (49, 359, 515). Furthermore, social attitudes that condemn girls who plan for sex, combined with perceptions that planning for sex spoils romance, may not stop sexual activity but may inhibit contraceptive use. Such attitudes increase girls' vulnerability to sexually transmitted disease (STDs) and pregnancy (49, 515). Also, young women, especially those involved with older partners, may be too embarrassed to discuss or negotiate contraceptive use. Some young people cannot use contraceptives because sexual intercourse is unwanted and forced (see Chapter 2.2, Sexual Violence and Coercion).