Why is African Teen Fertility So High?
And what does this mean for women?
Teenage fertility has fallen globally. Yet one region bucks the trend. Why is teen fertility still high in Sub-Saharan Africa, and what does it mean for women?
Fundamentally, economic stagnation drives Sub-Saharan Africa’s exceptional fertility trajectory. Without structural transformation and rising productivity, it is hard to envision let alone gain upward-mobility via skills.
Diverse cultural ideals then shape how individuals try to gain status and social inclusion. Teenage marriage and fertility are highest across the Islamic Sahel, where communities privilege large families, female seclusion and the afterlife. Further South, women exercise far greater independence. Navigating precarity, some look to men as providers, but this comes with vulnerabilities - such as transactional sex.
Systematically, this essay examines how failed structural transformation, limited technology and weak ideals of romantic love create a teen fertility trap. Sub-Saharan Africa is diverging from the rest of the world, with massive implications for women.
By 2035, 66% of teen births will be in Sub-Saharan Africa
Sub-Saharan Africa differs in two crucial respects - explain Spoorenberg, Carlsen, Flatø, Stonawski and Skirbekk. Historical fertility means it has a large number of teenagers. Additionally, teenage pregnancy is high. Combined, these dynamics mean that by 2035, two-thirds of all teenage births will occur in Sub-Saharan Africa.
Their analysis draws on several key data sources, primarily the UN World Population Prospects 2022, which synthesises censuses, demographic surveys, and vital registration systems.
Africa’s weak state capacity means we should treat statistics with caution. To strengthen our understanding, this essay incorporates a wealth of experiments, surveys, meta-analyses, and my own ethnographic insights from Zambia and The Gambia.
The Great Teen Divergence
Historical data reveals a dramatic divergence in teenage fertility. China's teenage fertility rate plummeted from 84 to 12 births per 1,000 females aged 15-19 between 1950 and 2020. India achieved an even more impressive reduction, slashing rates from 144 to 17 per 1,000.
Yet Nigeria charts a different course. Now leading globally in adolescent births, Nigeria's rate has declined only modestly from 122 to 102 per 1,000. By 2030, Nigeria alone will record more teen births than China and India combined.
Compared to 1950, most countries have reduced teen fertility by around 50-75%. Sub-Saharan Africa persistence demands a comparativist explanation.
Why is Teenage Fertility so High?
Demographers typically highlight three key barriers: limited contraceptive access, low education, and early marriage. Let’s explore these and their underlying drivers.
Contraceptive access
Sub-Saharan Africans’ contraceptive use lags far behind the global average. Though we should also recognise progress (doubling from 14% in 2000 to 28.3% in 2020) and variation (from 2% in Somalia to 57% in Botswana).
This matters profoundly. As demonstrated by Goldin and Katz: the pill enables women to continue their education and pursue careers! Without it, women are trapped by their biology.
That said, ‘use of contraceptives’ isn’t just about supply, we also need to understand demand.
Education
Teen fertility is correlated with low rates of education.
Countries with teen fertility rates above 100 per 1,000 tend to have female secondary school enrolment below 45%. By contrast, every nation that has reduced rates below 20 per 1,000 maintains enrolment above 60%.
Across much of Sub-Saharan Africa's youthful population, secondary schooling remains low. In Niger, Mali, and Chad, teenage girls average just seven years of education. Ghana meanwhile has higher education and lower teen fertility.
India is below the expected line - even though most girls are going to school, teen fertility remains low. This is because most are strictly cloistered, with prohibitions on loitering.
Early marriage
In Sub-Saharan Africa, 37% of young women married before turning 18, with 72% of births under 18 occurring within marriage.
Watch out for heterogeneity! Ghana’s rate of early marriage and teen fertility is well below Niger’s.
Are Teen Pregnancies due to the failure of Structural Transformation?
Without economic transformation, families and young women struggle to imagine skills-based pathways to status.
Sub-Saharan Africa GNI per capita remains ultra low. Most people work on farms - which are usually small and unproductive. Only 3.5% of agricultural land is irrigated.
African firms tend to grow very slowly, constrained by expensive credit, relentless power cuts, and high transport costs. In Guinea-Bissau, entrepreneurs told me that power was so unreliable, they needed to buy a generator, but that was prohibitively expensive, invariably curbing labour recruitment and pushing up prices. Segue: that was also when I stayed on a friend’s mattress and got scabies.
Still, poverty is not a full explanation. Bangladesh and Ghana share similar per capita wealth and secondary enrolment rates, yet Ghana’s fertility is nearly double. To understand this divergence, we must examine how poverty interacts with culture and technology.
Does Limited Technology hobble Cultural Leapfrogging?
Loyal readers will recall my suggestion that smart phones enable young women all over the world to hop online and culturally leapfrog to the egalitarian frontier. In Turkey, Malaysia, and Mexico, young women are using Instagram and Netflix to imagine different futures. Swiping past local traditions, they are exploring alternatives.
But barely half of Sub-Saharan Africans have access to electricity. Only 18% of young people have mobile internet. In rural villages, where electricity, phone signal and internet access are seriously patchy, people remain tethered to local ideas of prestige. As the Bemba say,
“umwana ashala atasha nyina ukunaya”
(the child who doesn't travel praises their mother's cooking).
What about Religion?
Most Sub-Saharan Africans say that religion is extremely important and that they attend worship services every week. Thankfully, two brilliant papers have quantified how Christianity and Islam affect education and fertility in Africa.
It makes sense to study these issues concurrently, since communities that devalue girls’ education see little cost to early marriage and childbearing.
How does religion shape educational mobility?
Alberto Alesina, Sebastian Hohmann, Stelios Michalopoulos and Elias Papaioannou examine educational progress throughout postcolonial Africa. Merging census data from 21 countries, they present strong evidence of religious differences.
Christian Africans (compared to Muslims and traditionalists) typically have greater intergenerational mobility. This is partly because they have more educated parents and live in more prosperous places. However, when when controlling for parental education and location, they still find a Christian advantage.
How big is this difference?
Of Cameroonian parents who completed primary school, 96% of Christians will complete primary, compared with 80% of Muslims.
The Christian-Muslim mobility gap is larger in regions where many people are Muslims, and where there was a large Christian-Muslim gap in literacy during colonialism. Long-run effects persist partly because Muslims are less likely to move to areas of upward educational mobility.
What explains these religious differences?
Alesina et al’s evidence doesn’t allow them to speculate. They suggest it could be
1. Social norms
2. Religious educational infrastructure (like maktabs)
3. Political economy and the power of religious leaders.
All three seem plausible and likely mutually reinforcing.
In places where religious leaders are more powerful, enshrined Sharia law, and built more madrasahs, we might expect that people will be more Islamic. In Nigeria, districts that were once under the Sokoto Caliphate, where Sharia law is codified, have much lower rates of female employment outside the home compared to other Muslim areas.
72% of Nigerians say that one of the most important qualities for children is religious faith. This figure is much higher above Muslims (81%) than Protestant Christians (65%).
If religious devotion is widely esteemed, children may emulate their peers, thereby gaining social inclusion and status. Seldom seeing others advance through education, you may not necessarily see it as a route to upward mobility. Instead, you may take great pride in reciting scripture, being regarded as pious, and hopefully getting to paradise.
How does religion affect fertility?
If Muslim Africans are less likely to get educated or migrate to prosperous regions, this may also affect their view of Becker’s ‘quality-quantity trade-off’. We might expect Muslim Africans to have earlier marriages and larger families.
And that’s precisely what’s found by Phoebe Ishak and Mark Gradstein. Drawing on Demographic and Health Surveys for 24 African countries, they finding a strong correlation between religion and fertility. But maybe this reflects prior culture or geography, rather than religion?
Building on Micholopoulos et al 2019, they argue that Islam spread via trade networks. Proximity to ancient trade routes can thus be considered an exogenous shock, encouraging Muslim conversions. With this instrument, they find that contemporary Muslims typically have one more child.
The correlation also holds among co-ethnics. Muslim members of an ethnicity are more likely to have more children than Christians of the same ethnicity.
As a third battery of tests, they find that religious differences remain significant even after controlling for ancestral cultural practices like polygamy and bride price.
Religious community matters. Muslim belief is irrelevant in places where Muslims are a minority. It’s only where Muslims comprise more than half the population that religion is associated with fertility. This echoes Alesina et al’s finding that the Christian-Muslim mobility gap is larger in regions where many people are Muslims.
Why is fertility higher among Muslim Africans?
Drawing on DHS data, Ishak and Gradstein find that Muslim African women are less educated, marry younger, give birth earlier, are less likely to work, and less able to achieve their preferences.
Higher fertility among Muslim Africans does not reflect women’s preferences. Muslim African women have more children than they want. Muslim African husbands tend to want more kids, and are more able to realise their preferences
Religious Communities
These two studies on education and fertility indicate the importance of religious community.
Poor, precarious, informally employed people remain heavily reliant on peer networks. They don’t have the economic independence afforded by secure salaries or government pensions. Trust, respectability and social approval matter enormously.
Tight-knit communities may also eye individualism and deviance with suspicion - ostracising deviants. So it makes sense that the Islam effect is significant when Muslims are surrounded by other Muslims, collectively enforcing a particular set of values.
Paradise and Seclusion
In Northern Nigeria’s Hausaland, married women traditionally observe ‘kulle’ - seclusion. Married women of reproductive age are expected to remain hidden. High walls are built around a central courtyard, with offset entrances (zaure) that prevent outsiders from seeing inside. Houses for married women are ‘ba shiga’ (no entry), as unrelated men are forbidden. Within these walls, women undertake childcare and food preparation.
‘Kulle’ began in the fifteenth century among the elite in Kano - marking status, and later spread via conquest and slavery. Under the Sokoto Caliphate, seclusion marked Islamic piety and women’s status as free Muslims. In Sokoto’s extensive slave plantations (rimjis), farm work became stigmatised as slave labor, creating lasting associations between seclusion and free status. While there was historical diversity, by the 1950s, growing trade wealth and urban infrastructure (especially water access) made seclusion increasingly feasible for merchant families across the region. What began as an elite practice became a broader aspiration.
Recent surveys and observations suggest that married women rarely appear in public spaces like markets or mosques. When they venture out, it’s usually at night in groups, or during special occasions like naming ceremonies or religious festivals, and then only while veiled. While boys often attend mainstream schools, girls are typically sent to Islamiyya schools, which prepare them for a life of seclusion.
Teachings of wifely obedience can non-consensual sex - as one adolescent male explained,
“I want to tell you, it is good to beat her, because I’m already married to her and she’s obliged to satisfy my sexual needs as long as she lives with me”.
For rural Muslim men in Niger, “Contraception was a threat to his masculinity because it challenged his ability to raise children. Despite the Nigerien government's sustained efforts to promote family planning, modern practices associated with sexuality and reproduction are met with suspicion by large segments of the population: they defy men's conjugal rights and their authority over women and are also perceived as a challenge to Islamic teachings”
Across the Sahel, adolescent fertility is seriously high
Chad, Mali and Niger register Africa’s highest rates of teen marriage and teen pregnancies: over 70% of young women were married under 18.
In Nigeria, 23% of 15-19 year olds are already mothers or are pregnant with their first child.
40% of Muslim Nigerian women were married before turning 15.
In Kano, Northern Nigeria, only 7% of married women make informed decisions about their own use of contraceptives or sexual relations, and only 11% use contraceptives. The median woman first had sex at 16.
In Karu, the median female age at first sexual encounter is 14.8.
Importantly, none of this is entailed by religion. North of the Sahara, in Muslim-majority Tunisia, fertility has collapsed. Sub-Saharan Africa’s exceptionally high fertility reflects a potent combination: economic stagnation, limited education, and intense religiosity create mutually reinforcing constraints.
Permissiveness, Poverty and Fertility
Africa is not a monolith. Beyond former Islamic caliphates and conflict zones, teenage girls move freely, chatting with boys without brotherly reprimands. Adolescents in Ghana and Kenya run errands alone and socialise openly. All this is perfectly permissible. In Kitwe, Zambia, my host explicitly told me to greet everyone in the ginormous market so as to appear friendly and social!
All this interacts with economic stagnation, weak states, low education and limited technology. If home is stressful, school is dull, and you have nothing else to do, then men’s gifts and affection may be relatively tempting.
Free to mingle, young women may pursue intimate relationships as a way to get ahead. ‘Transactional sex’ refers to relationships where parties exchange sex, gifts and money, but is not seen as ‘prostitution’. The remainder of this essay draws on a wealth of research, including my own in The Gambia and Zambia, to explore how this affects fertility and women’s autonomy.
Transactional Sex
“You use what you have to get what you want” - say the young women in Abuja Nigeria. Other sayings include, “A tight hand is a tight pussy”; and “When you open your legs, you eat; When you close your legs, you starve”.
In rural Mwanza, Tanzania, transactional sex underlies most non-marital relationships. One 1998 survey found that 75% of sexually active women received gifts or money at first intercourse, while 43% of men reported providing gifts. Another survey of Tanzanian adolescent girls and young women out of school found that 35% were engaging in transactional sex. But other estimates are much lower.
When men's primary contribution is material, desirability hinges on financial muscle. Teachers, government employees and business owners may be highly sought. When I was working in The Gambia, a male colleague had a wife in each of our ‘beneficiary communities’. In Malawi, female fish traders may exchange sex with fishermen for more favourable prices. In rural Tanzania, intimate relations are characterised by ‘tamaa’ (meaning desire, greed, or lust). As locals say,
Is Transactional Sex a function of Poverty?
Poverty certainly drives these patterns. Across Africa, transactional sex is most common among women with less education. In Western Kenya, household shocks - like family illness - increase women’s likelihood of engaging in unsafe sex.
But transactional sex isn’t just for survival. Research by Joyce Wamoyi and colleagues reveals that young women also pursue transactional sex for prestigious consumer goods - scented beauty products and fashionable clothing that enhance social status.
Economic stagnation amplifies these dynamics. Without engaging education or viable employment prospects, what are the alternatives? Charismatic and generous men may seem extremely tempting.
Cultural permissiveness also allows these relationships to flourish openly. We are not simply economically maximising agents. In African societies where teenage girls are not cloistered, they can move around without chaperones and forge relationships. But sexual permissivity does come with risks..
Transactional sex elevates risks of pregnancy
When men provide money and expect sex, but feel little emotional attachment, intimate relations become extremely risky. Research across Sub-Saharan Africa reveals consistent patterns of unsafe sex, veneral disease, HIV/AIDS, sexual violence, unwanted pregnancy and school dropouts:
Tanzanian women engaging in transactional sex were less likely to use condoms and more likely to have HIV;
In Soweto, South Africa, women who report transactional sex are more likely to have had early sex, experienced violence by male intimate partners, and have HIV;
In Kisumi, Kenya, women who receive larger amounts are less likely to use condoms;
17% of sampled Sub-Saharan African teenage girls said they sexually abused last year. This ranged from 6% in Zimbabwe to 28% in Malawi. Risks apply whether they are in or out of school.
Over 40% of first-time mothers are unmarried in Gabon, Namibia and Swaziland.
In regions where girls move freely yet struggle to access contraception, transactional relationships often lead to pregnancy and school dropout. Once mothers, young women frequently face abandonment. Sub-Saharan Africa now shows the world’s highest rates of single motherhood.
To illustrate these dynamics in greater depth, I now present my ethnographic research from The Gambia and Zambia, which are respectively Muslim and Christian.
Ethnographic Insights from the Gambia
In 2008, I got my first research job - working for Sylvia Chant, by studying young love, sexuality and poverty in The Gambia. Over the course of six months, I chatted to young people in shanty compounds, markets and hairdressing salons.
Although the overwhelming majority of Gambians are Muslims, at the time there was minimal Arabisation. In the entire country, I only met one woman who veiled. Most women wore sleeveless tops. In my youthful ignorance, I did not find this remarkable. But of course it reflects a culture without seclusion or segregation.
Men expressed care with small gifts and favours. As Ramatoulie, a 22-year old hairdresser explained: “If you love someone, you have to spend”. Momodou, a 26-year old taxi driver likewise shared: “I like to spend for my girlfriend... just to show her that I love her, even not that, I like to help her”. Hadim, a 28-year old teacher, added: “Pride will not allow you to be seeing your girlfriend every day or every time and that she needs something and that you cannot at least solve one or two problems of hers … you will have to give her something to solve her problems”.
As young women pursued men with more financial muscle, poorer men got left on the shelf. Mohammed, a 24-year old who worked various jobs as a chef, electrician and plumber, expressed a common male perspective:
“If you are chasing a girl, before she accept, she will like to know whether you are [financially] strong or not... They don't care for boys unless you get. That is the main problem here in The Gambia between the boys and the girls”.
Abdoulie, a 30-year old woodcarver who shared a bed with a male friend due to poverty, explained: “they will underrate because you've got nothing to give”. His friend Saul revealed that when he was unable to satisfy his previous girlfriend’s requests she would “change her face”, become “so stressed” and sometimes “not even speak with him”.
Amid poverty, many women were economically shrewd - favouring more financially secure partners, or keeping many concurrently. As Soffie (age 21) advised:
“This small, small [young and financially weak] boyfriends, she will love them. After, those boys they are going to find another person, every time your heart will break, it's better to find a big [financially strong] boyfriend who will give her, because if she has nobody she will go and have sex with them anyway so it's better for him [her] to have a big boy”.
In return for gifts, men usually expected sexual favours. Anne Marie, age 18, explained:
“When the boy… keep on giving me money every day, one day he will .. tell me: ‘I want to sleep with you, you eating my money, every time, can't you sleep with me?’ You refuse, he’ll just force me ... When they're giving you money they want something in return”.
Not all women accepted this trade. Anne Marie prioritised study:
“I don't like having boyfriends because they are not serious, and they used to force you for sex... I want to follow my education. If I stay here, have my good job and help my mum, that’s what I plan. Sometimes when I don’t have money I will think and think and think: What can I do? I will go and work! I will go and find a job so that I have money”.
Individuals vary, but the overarching story from my Gambian interviews is that young women strategically pursued relationships for economic gain, wherein they were often pressured to have sex.
Ethnographic Insights from Zambia
During my 18 months in Zambia, I lived in both urban shanty compounds and a swampy village - sleeping on the floor, making fire, and washing behind an old sack of maize meal.
Rural Insecurity
Rural life was quiet, isolated by lack of electricity, running water or phone signal. The nearest health clinic was two hours walk. Without TV or smartphones, there was little to see or imagine beyond the small, homogenous village.
When girls got pregnant, they usually dropped out of school and married. But they often lacked resources, support systems or much understanding of the world. Child brides are more likely to be abused. One morning, a doctor and I found a young bride by the roadside, her face swollen and body covered in cuts, as if dragged through the field. At sixteen, she wanted to escape her violent marriage - but where? With no job prospects or support systems, many women feel trapped.
According to Zambia’s Demographic Health Survey 2024, only 50% of women use contraceptives, while 46% of 19 year olds report having had a live birth.
Motherhood Gives Status!
Low use of contraceptives isn’t just about access, but demand.
In Zambia, women become known by their first child’s name - if your son is Mwape, you become “BanaMwape” (mother of Mwape). During my fieldwork, women constantly encouraged to have a baby. Immersed in these ideologies, they may be taken for granted. Thus despite high fertility, most women want more children.
But this comes with risks.
A couple of months ago, I received a message on Instagram. A Zambian friend (with 5 children) had been abandoned by her husband. He had re-married, and taken all their assets. Destitute, she was now living in a shack. She couldn’t simply make money because she didn’t have the capital to buy dried fish for re-sale. Obviously I wanted to send money, but even that was difficult since she didn’t have her own phone, and there was no local infrastructure for digital payments. Instead, another relative had to travel six hours to Lusaka to physically pick up the cash.
Urban Precarity & Women’s Vulnerability
I spent six months living in an extremely poor neighbourhood with a locally elected councillor. Walking home, it was pitch black - no street lights, tarmac roads, or indoor water. When I washed, I filled a bucket and threw it over my head behind an old sack of maize. One time it got nasty, there had been a toxic leak and my eyes stung. We cooked on fire and scrubbed our clothes by hand. Barely anyone had a salaried job.
For three months, I sat at the back of several local classrooms. Absenteeism was rife. We had six classes in a day, teachers typically came to two. Rote learning was typical, lessons were written on the blackboard. Otherwise, teen had nothing to do. They were bored. One time, the neighbouring class was noisy and unsupervised. So our teacher beat them all with a hose pipe.
Mutinta - my host family’s teenage daughter - fared terribly in school, had recently become pregnant and moved out, but her boyfriend was awol. Having dropped out of school, Mutinta’s situation was precarious. When his new girlfriend passed, they had a bitter street fight - yanking hair and pounding each other on the dusty ground.
Sexual permissiveness without contraceptives means serious vulnerabilities.
Marriage is no panacea. Women who have five children, and lack independent salaries, depend heavily on their husbands. This deters exit. Victims of male violence sometimes came - bloodied and bruised - asking the councillor for help. One had an engorged eye, her entire face was red, swollen and terribly disfigured. She asked for advice. But what were her options?
Even if marriages are peaceful, women face enormous stress. Widespread youth unemployment and ‘sugar daddies’ generate heightened intra-female competition.
Women’s response? “Ukushipikisha” - to endure.
Sub-Saharan Africa’s Teen Fertility Trap
Global fertility rates reveal a stark divergence. While most regions see rapid decline, Sub-Saharan Africa remains trapped by economic stagnation, poor schooling, and limited connectivity.
Cultural heterogeneity shapes responses across Africa. In the Islamic Sahel, religious communities prioritise early marriage and large families. Teen pregnancies are thus especially high in Niger and Mali. Further south, adolescent girls move freely through public spaces, forging their own ties - but these strategies can include transactional sex, which carries risks including abuse and pregnancy.
Sex without romantic love is dangerous - in both cases. If a man has the upper hand, yet lacks deep affection, then her wants and welfare matter less. Instead, he may impose his preferences for seclusion, multiple children, or unsafe sex.
Structural transformation, skills-based pathways of upward mobility, and internet connectivity could shift people’s aspirations. Ghana for example is making progress. But in much of Sub-Saharan Africa, climate breakdown and conflict create a teenage fertility trap.
My Previous Work
Wider Research
Excellent essay! I like how much you focus on the demand side of contraceptives & transactional sex and what drives it. It reminded me of an older post by Adam Tooze in which he cites a study showing that
"even with higher education 66.7 percent of Nigerian women in 2018 used no contraception. "
https://adamtooze.substack.com/p/chartbook-121-youth-quake-why-african
He argues (or his source material does) that Nigerian women with high education still
"want large families and they are, in their own way, quite successful at matching actual fertility to desired fertility."
Do you know more about this? There is no discussion in his article of differences among religious groups or how many of these women with higher education also actually tend to have a job.
Damn! Alice. I don’t even know you, but I admire you sm for this! Instead of just saying rapey ass men, lack of female anatomy and autonomy, contraception and choice but a whole lot of pseudo ideological manipulation (I think ideological manipulation are your words) from the male sex and male minded women as being some of the many reasons fertility is still so high in sub- Saharan Africa. You do all this data driven research! I for one appreciate it!