Characteristics Linked To Sexual Debut Vary Across Sub-Saharan Africa

First published online:

The associations between urban youths’ social and demographic characteristics and the timing and context of their sexual debut—such as whether it occurs before marriage and without contraception—often differ across cities and countries in Sub-Saharan Africa, according to an analysis of survey data from Kenya, Nigeria and Senegal.1 For example, the likelihood that a young urban woman is unmarried the first time she has sex, and the probability that she used a contraceptive method, varies according to wealth in Kenya, but not in the other two countries. Education and age at first sex are positively related among young urban men in Senegal (odds ratio, 1.7), but negatively related among those in Kenya (0.6). Moreover, within a country, the circumstances surrounding sexual debut may differ according to city of residence; young men in Ilorin and Kaduna, Nigeria, for instance, are far more likely than their peers in Abuja to use a contraceptive method at first sex (4.0–4.3).

The study used baseline survey data from a program to improve reproductive health among poor urban residents of Kenya, Nigeria and Senegal. In each country, the program was implemented in three or four cities. The sampling procedure differed slightly across countries. In Kenya and Senegal, the researchers stratified primary sampling units as poor (informal slums) or nonpoor (formal settlements), then chose an equal number from each category; because primary sampling units in Nigeria could not be categorized, the researchers randomly selected a representative sample. In all three countries, the investigators randomly selected 21–41 households in each primary sampling unit, and recruited all women aged 15–49 who had spent the night in the household; in half of the households, men aged 15–59 who had spent the previous night were also invited to participate. Participants completed a detailed survey that covered a range of reproductive health issues.

The current analysis focused on youth aged 15–24; the number of young women in the analytic samples ranged from 2,307 in Kenya to 4,029 in Nigeria, while the male samples ranged from 738 in Kenya to 1,680 in Nigeria. In addition to compiling descriptive statistics, the investigators performed regression analyses to identify characteristics associated with age at sexual debut, marital status at first sex, and use of a modern contraceptive method at first sex.

Most young women and men in the three countries had a primary or secondary education and had never been married. Kenyan youth tended to be older than those in Nigeria and Senegal (seven in 10 were aged 20 or older, compared with half of those in the other two countries). The proportion of respondents who were Muslim ranged from one in seven in Kenya to nine in 10 in Senegal.

Most Kenyan youth had had sex (79% of males and 72% of females), but fewer than half of those in the other two countries had done so (28–35% of males and 32–44% of females). The vast majority of sexually experienced young men—about 96% in all three countries—had had sex for the first time before marriage; the corresponding proportion among females ranged from 36% in Senegal to 74% in Kenya. The proportion of sexually experienced youth who had used a modern method of contraception at first sex was higher among males (20–33%) than among females (8–17%); in most cases, the method was a condom.

In general, the predictors of age at first sex, premarital sex and contraceptive use at first sex varied across countries, especially among men. In all three countries, the likelihood that a woman had had sex at a given age was reduced among those with at least a secondary education and those who were working or in school. However, other characteristics did not show consistent associations. For example, in Nigeria, young women in the four least wealthy quintiles were more likely than those in the richest quintile to have had sex at each age (hazard ratios, 1.2–1.5); however, no association was apparent in Kenya, and in Senegal only women in the two poorest quintiles had an elevated likelihood of having had sex at a given age. Women who had moved in the past year were more likely than those who had always lived in the same place to have had sex, but only in Nigeria and Senegal (1.3 and 2.5, respectively). City of residence was largely unrelated to age at first sex.

Different patterns emerged among young men. In Senegal, males who had continued their education beyond the secondary level were more likely than those with less than a secondary education to have had sex at any given age (hazard ratio, 1.7), but in Kenya they were less likely to have done so (0.6). In Kenya, those who were working or in school were more likely than other men to have had sex (1.4), but the same was not true in the other two countries. Few associations were apparent between age at first sex and wealth, religion or duration of residence. City of residence was associated with sexual debut only in Nigeria; compared with their counterparts in Abuja, young men in Ibadan or Ilorin were more likely to have had sex by a given age, whereas young men from Kaduna were less likely to have done so.

Because nearly all male respondents had had premarital sex, the analysis of marital status at sexual debut was limited to females. In all three countries, the likelihood that first sex had occurred before marriage was inversely associated with age at first sex, and positively associated with education level; the latter finding was especially strong in Nigeria and Kenya, where the odds that first sex was premarital were far greater among women with a secondary education (odds ratios, 2.0–3.6) or more than a secondary education (7.9–9.8) than among those with a primary education or less. Muslim women were less likely than those who were neither Muslim nor Catholic to have had a premarital sexual debut (0.1–0.4). Other characteristics—including wealth, employment and schooling status, and duration of residence—were associated with premarital sex in at least one country, but not all three.

Finally, the researchers examined predictors of contraceptive use. In all three countries, young women were far more likely to have used a modern method at first sex if they had been unmarried (odds ratios, 2.6–7.3) or had more than a secondary education (4.0–4.8). Household wealth was consistently associated with contraceptive use only in Kenya, where the wealthiest women were more likely than others to use a method. Age at first sex was positively associated with contraceptive use in Kenya, but not elsewhere; Muslim women were less likely than other women to use a method in Senegal.

Among young men, age at sexual debut and education were positively associated with contraceptive use at first sex. Few associations were apparent between contraceptive use and wealth, religion or duration of residence. However, use differed by city; in Nigeria, young men in Ilorin and Kaduna were more likely than those in Abuja to have used modern contraceptives (odds ratios, 4.3 and 4.0, respectively), while in Kenya men in Kisumu were more likely than those in Nairobi to have used a method (2.0).

One limitation of the study, the authors note, is that it did not distinguish between wanted and coerced first sex; other limitations include the study’s focus on a small number of cities in each country—an issue that may be especially relevant for Nigeria, which is large and diverse—and its reliance on self-reported data.

Although some study findings were consistent across countries and between women and men—in particular, the finding that more educated youth were more likely than their peers to delay having sex and to use protection—other associations varied among countries, and findings even differed among cities in the same country. This variation, the authors note, underscores the need for regional policymakers and programs "to undertake needs assessments to understand the local context that influences the timing and circumstances of first sex." The information that results from these assessments can, in turn, be used to "tailor programs to better reach youth [who are] engaging in premarital and unprotected sex."—P. Doskoch


1. Speizer IS et al., Timing and circumstances of first sex among female and male youth from select urban areas of Nigeria, Kenya and Senegal, Journal of Adolescent Health, 2013, doi: 10.1016/ j.jadohealth.2013.06.004, accessed Aug. 5, 2013.