Why it happens
Child marriage is a complex issue. It is rooted in gender inequality and the belief that girls and women are inferior to boys and men. It is made worse by poverty, lack of education, harmful social norms and practices, and insecurity. Its drivers vary between communities and it looks different across – and within – regions and countries.
Gender inequality means that women and girls are treated as second-class citizens, denied their human rights and valued less because of their sex.
Child marriage is one expression of this gender inequality.
Patriarchal systems – that is, systems that are controlled by men – that value girls according to their virginity lead to limits on female sexuality and reproductive choices. This can mean controlling how a girl behaves and dresses, where she goes, who she sees, and if, who and when she marries.
It can also criminalise her sexuality and block her access to care and information.
In many places, girls who have relationships or become pregnant outside of marriage are shamed for bringing dishonour on their family,  or even stopped from going to school. In such circumstances, parents may see early marriage as a way to protect their daughters and their families. Girls may agree, and wish to gain status as a wife and mother.
Explore the links between gender equality and child marriage on our Gender learning page and gender equality brief.
Social norms and practices
Social norms are informal rules of behaviour in a group. People follow them to show they are members of the group, because of social pressure or coercion by power holders, or because it’s what they’ve always done.
Social norms are often gendered and aim to control girls' and women's sexuality, and maintain longstanding practices. Child marriage is one such practice. In many places, it has happened for generations and has become normal and accepted.
In some contexts, a girl becomes a woman when she starts to menstruate. Marriage may be the next step towards her gaining status as a wife and mother.
Harmful practices can be linked to each other. In some places, child marriage follows female genital mutilation/cutting (FGM/C), which is considered a rite of passage to womanhood  and a way to increase a girl’s marriageability. See our Health learning page for more information about FGM/C.
Nearly 40% of girls in the world's poorest countries are married as children, twice the global average.
When experiencing acute poverty, families – and sometimes girls themselves – see marriage as a way to reduce family costs and gain financial security.
This idea is reinforced by patriarchal norms that devalue and commodify girls.
Because girls have less access to education and low social, political and economic status, they are often economically dependent on men. They may see marriage as their only option.
Girls are most affected by poverty-driven child marriage because:
- They lack access to education and welfare and protection safety nets.
- They have less time to study and earn because they have to do more childcare and household chores than boys.
- Families with few resources are more likely to invest in their sons’ education.
- They can’t trade, own assets or do some jobs because they aren’t allowed to move freely.
- They can’t access fair employment because of workplace harassment and biased recruitment policies.
- Their marriage may be used to repay debts, manage disputes, or settle social, economic and political alliances.
- A dowry or “bride price” may provide a welcome income for a girl’s family in times of economic hardship.
- If the girl’s family has to pay a dowry, the amount may be less if she is young and uneducated.
For more information on poverty and child marriage, see our Economic Justice learning page.
The 10 countries with the highest child marriage prevalence rates are currently considered either fragile or extremely fragile.
The prevalence of child marriage increases during crises, with a 20% rise reported in Yemen  and South Sudan  as a result of conflicts.
Crises caused by conflict, generalised violence, natural hazards – including climate change and disease outbreak – hunger and poverty worsen the factors that drive child marriage. This is because:
- Families see child marriage as a way to cope with growing economic hardship.
- Parents marry their daughters because they think it will protect them from increased or generalised violence, including sexual violence.
- Displacement breaks down social networks and protection systems, making girls more vulnerable to child marriage.
- Girls may marry or enter informal unions with older men who promise to reunite them with family members who have already migrated or been displaced.
- Child marriage is used as a weapon of war and to hide human trafficking and sexual abuse.
- Access to education is reduced, and schools and children may be targeted or recruited by armed actors. This puts girls at increased risk of exploitation and abuse, including slavery and child marriage.
For more information on child marriage and insecurity, see our Humanitarian learning page.
 American Jewish World Service (AJWS) and al., Child, Early and Force Marriage and the Control of Sexuality and Reproduction, 2015
 Petit, V. and Zalk, T. N., “Everybody wants to belong: A practical guide to tackling and leveraging social norms in behaviour change programming,” PENN SoNG and UNICEF, 2019.
 Young Lives, Child Marriage and Female Circumcisions (FGM/C): Evidence from Ethiopia, Policy brief 21, July 2014.
 UNICEF, Child Marriage Global Databases, 2020
 Burkina Faso, Bangladesh, Chad, Central African Republic, Guinea, Mali, Mozambique, Niger, Somalia and South Sudan are listed as fragile states as defined by OECD. OECD, States of fragility, 2018.
 Marsh, M., and Blake, M., “Where is the Money?” IRC and VOICE, 2019
 Buchanan, E., “Born to be married – Addressing early and forced marriage in Nyal, South Sudan,” Oxfam, 2019