Blog post

Maternal Age Matters: for a lifetime, and longer

9 min read
2 Nov 2015

Maternal age matters—for the mother's own health and survival, for her child's well-being throughout his or her lifetime, and even longer if the well-described intergenerational cycle of growth failure continues into the next generation, according to a recent article published in The Lancet Global Health[1]


Causes and effects of young (≤19 years) maternal age

Despite an almost universal decline in the adolescent birth rate since 1990, adolescent fertility still accounts for 11% of all births worldwide, with 95% of these births occurring in low income countries and low middle income countries. In 2014, the average global birth rate among 15–19-year-olds was 49 per 1000 girls (1 in 20), with startling differences in rates between countries (from 1 to 299 per 1000), the highest rates occurring in sub-Saharan Africa. Early marriage remains a strong factor underlying adolescent fertility, with most adolescent childbearing (90%) occurring within marriage, although premarital conception for first births that occur within marriage is common[2].

A new study is adding to a growing body of evidence that young (≤19 years) and advanced maternal age (≥35 years) are associated with adverse birth and child outcomes. As described in The Lancet Global Health[3], the COHORTS Collaboration mustered the enhanced statistical power of pooling data from 19 403 participants located in five birth cohorts in Brazil, Guatemala, India, the Philippines, and South Africa, to identify an increased risk of low birthweight, preterm birth, stunting at 2 years, failure to complete secondary schooling, and lower adult height in children of young mothers (≤19 years) compared with mothers aged 20–24 years. Mothers were recruited for the study before or during pregnancy, and the children followed up to adulthood.

The article also points out different underlying factors responsible for preterm birth (in younger and older mothers) including socio-economic, biological and behavioural factors. Such factors have implications for designing cost-effective public health interventions. For instance, if effects are mostly explained by socioeconomic factors that happen to correlate with age, then interventions that simply delay age at marriage may have little effect.

Concomitant policy changes in other areas may have unintended consequences on adolescent childbearing. One example is the decision in Chile to lengthen the school day, resulting in a 5% reduction in adolescent pregnancy prevalence[4]. Introducing legislation on mandatory schooling, statutory rape, or a minimum marriage age may be similarly effective in decreasing adolescent pregnancies.

Ultimately, the challenge is to identify a combination of measures that is feasible within the financial and societal contexts of low income and lower middle income countries (LMICs). The study concludes that children of young mothers in LMICs are disadvantaged at birth and in childhood nutrition and schooling and recommends efforts to prevent early childbearing should be strengthened[5]. It also makes a strong case for continued and uninterrupted allocation of resources (even in situations of scarcity) through the life cycle, well beyond the current international mobilization around the “first 1000 days of life”[6] .

Interventions to address young (≤19 years) maternal age

Another recent systematic review,[7] specifically examining LMICs, identified various interventions aimed at reducing adolescent fertility. These included improved communication, peer education, school-based interventions, health counselling, and cash transfer programmes, many offered in combination. Programmes promoting or facilitating school attendance among adolescent girls reduced marriage and childbearing significantly. Conditional cash transfers performed best, [delaying] the age of marriage, and reducing the rate of, marriage, total fertility rates, and the prevalence of adolescent pregnancy. Evidence from a recent study on one of the pioneer conditional cash transfer programs in the world, The Female Secondary Stipend Program (FSSP) in Bangladesh introduced in 1994, estimates age at first marriage to be delayed by at least 0.4 years and finds age at first marriage to be lower on average for Muslim girls compared to non-Muslim girls[8][a].

The number of programs to address child marriage has grown significantly in the last five to ten years. However, this growth is still not keeping pace with the needs of the millions of girls who are at risk of child marriage every year, and the tens of millions of girls who are already married[9] . Some argue that interventions in this area are still largely research-driven i.e. theories are still being tested, with no roll-out of national initiatives in any LMIC.

Universal child support grants should be given closer attention as a cost-effective intervention to address child marriage and thus adolescent childbearing. Namibia and South Africa are at the forefront of such systems in LMICs. These are not specifically set up to address child marriage but rather to protect the most vulnerable children. Evidence from the Impact Assessment of the Child Support Grant in South Africa on adolescent risky behaviours reports[10]

  • reduced sexual activity and a fewer sexual partners, particularly when the adolescent also received the grant in early childhood
  • reduced pregnancy, again particularly when the adolescents also received the grant in early childhood

The assessment also concludes that the Child Support Grant promotes nutritional, educational and health outcomes. Early receipt significantly strengthens a number of these impacts. This is an investment in people that reduces multiple dimension indicators of poverty, promotes better gender outcomes and reduces inequality. The Assessment also finds that adolescents receiving the Child Support Grant are more likely to have some positive educational outcomes, are somewhat less likely to experience child labour, and are significantly less likely to engage in behaviours that put their health and well-being at serious risk.

Child support grants are relatively easy to administer and scale up. Namibia is about to expand its comprehensive social protection system to provide a universal child grant system, replacing the current grants targeted at just a few groups of particularly vulnerable children.

In 2004, the Ministry of Gender equality and Child Welfare (MGECW) inherited responsibility for the administration of child welfare grants from the Ministry of Health and Social Services (MOHSS). Between 2002 and 2014, child welfare grants expanded from 9,000 to approximately 164,000. Despite this expansion (both in terms of numbers of grantees and resources allocated to administration) and a considerable parallel drop in child poverty from 43.5% in 2003/2004 to 34% in 2009/2010[11], one in three children in Namibia were still growing up in a poor household according to the Child Poverty in Namibia report published in 2012[12].

This report also provides evidence on the effectiveness of social grants in reducing child poverty, and simulates some options for expanding child welfare grants and the impact this would have on household poverty. The analysis of simulated options projects a drop in child poverty rates from 34% to 13% upon introduction of universal child welfare grants for all children under 18.

Global evidence on inclusive child-sensitive social protection, meanwhile, has demonstrated that the impact of social grants on child poverty, vulnerability, and social inclusion can be maximized when coupled with investments in public social services in health care, nutrition, education and protection[b][13]. This combination of cash and services has the potential to be truly transformative for children’s lives with significant impact on adolescent risky behaviours - reducing sexual activity and pregnancy in adolescent girls, particularly when the adolescent receives the grant early in childhood.

Meanwhile, in Botswana, a randomized control trial on Young 1ove´s “sugar daddy” HIV education intervention is underway[14]. Modeled after a similar intervention delivered and studied in Kenya, it attempts to educate young adults about the relative likelihood of HIV infection among men of different age groups and to correct the misconception that young men are more likely to carry the virus. In fact, “sugar daddies” (older partners) are nine times riskier.

In Kenya, this intervention was shown to reduce pregnancy - a proxy for unprotected sex and HIV - by 28%. Young 1ove has adapted the intervention to Bostwana and already reached 32,010 youth. If the evaluation of the intervention shows a large, positive result in Botswana and there is a clear path to scaling-up, Evidence Action[15] plans to support Young 1ove´s scaling-up across other southern African countries with high HIV rates. The “sugar daddy” intervention has the potential to be low cost and sustainable because it can be integrated into existing government curricula.

Moving Forward – Giving What We Can´s approach to address young maternal age

In closing, exploring emerging thinking on “systems change” and “collective impact” which may be better suited to the endeavour of child marriage prevention[16], and understanding the cost effectiveness of cash transfers and universal child support grants in addressing adolescent childbearing are themes to be investigated further by Giving What We Can. One place to start is the Pixel Project[17], which lists 16 organisations involved in ending the practice of child marriage. Progress on measuring the impact tailored “sugar daddy” education programs have on protecting adolescent girls from HIV and pregnancy should also be followed up and incorporated into Giving What We Can´s research on cost-effective interventions that address young maternal age and HIV in adolescent girls.

In the meantime, 39,000 adolescent girls become child brides every single day, often married to much older men[18]. UNICEF Namibia is quoted in the media this year[19] saying that “according to the 2011 National Census, about 26% of Namibian girls gave birth to their first child before their 18th birthday. Across Eastern and Southern Africa, 12% of the girls are already married before they turn 15, while 38% are married before their 18th birthday. Children in rural areas and those from the poorest families are most at risk of child marriage and teenage pregnancy.” UNICEF is therefore pledging its commitment to the Namibian government’s strategies to empower families economically through child welfare grants.


  1. The Lancet: Maternal Age Matters, for a Lifetime and Longer
  2. The Lancet: Maternal Age Matters, for a Lifetime and Longer
  3. The Lancet: Association between maternal age at childbirth and child and adult outcomes in the offspring: a prospective study in five low-income and middle-income countries (COHORTS collaboration). Lancet Glob Health. 2015;(published online May 19.)
  4. Journal of Public Economics: Risky behavior among youth: incapacitation effects of school on adolescent motherhood and crime in Chile.
  5. The Lancet: Association between maternal age at childbirth and child and adult outcomes in the offspring: a prospective study in five low-income and middle-income countries (COHORTS collaboration).
  6. The efficacy of reduced adolescent childbearing in low- and middle-income countries: a systematic review.
  7. Effect of Girl’s Secondary Stipend on Schooling and Age at Marriage:Evidence from Bangladesh
  8. ICRW-Power to her: How empowering girls can end child marriage
  9. The South African Child Support Grant Impact Assessment
  10. The Namibia household Income and Expenditure Survey (NHIES) 2009/2010
  11. Child Poverty in Namibia – a child-centered analysis of the NHIES 2009/2010, National Statistics Agency, 2012
  12. Evaluation report - Unicef." 2015. 2 Nov. 2015
  13. Young 1ove is an organisation with the sole aim of protecting girls from HIV by highlighting the risks of "sugar daddies" who trade gifts for sexual relationships.
  14. Evidence Action scales proven development solutions to benefit millions of people around the world. We fill the gap between knowing “what works” and having impact at scale. "
  15. Giving What We Can: Child marriage report, p. 27
  16. The Pixel Project: 16 Organisations Working to Stop Child Marriage
  17. Care: Child marriage
  18. Namibia sun: over 5400 child marriages in Namibia