Determinants of cumulative fertility in Kenya

The health consequences of child marriage: a systematic review of the evidence

Background

Child marriage, defined as marriage before 18 years of age, is a violation of human rights and a marker of gender inequality. Growing attention to this issue on the global development agenda also reflects concerns that it may negatively impact health. We conducted a systematic review to synthesize existing research on the consequences of child marriage on health and to assess the risk of bias in this body of literature.

Methods and findings

We searched databases focused on biomedicine and global health for studies that estimated the effect of marrying before the age of 18 on any physical or mental health outcome or health behaviour. We identified 58 eligible articles, nearly all of which relied on cross-sectional data sources from sub-Saharan Africa or South Asia. The most studied health outcomes were indicators of fertility and fertility control, maternal health care, and intimate partner violence. All studies were at serious to critical risk of bias. Research consistently found that women who marry before the age of 18 begin having children at earlier ages and give birth to a larger number of children when compared to those who marry at 18 or later, but whether these outcomes were desired was not considered. Across studies, women who married as children were also consistently less likely to give birth in health care facilities or with assistance from skilled providers. Studies also uniformly concluded that child marriage increases the likelihood of experiencing physical violence from an intimate partner. However, research in many other domains, including use of contraception, unwanted pregnancy, and sexual violence came to divergent conclusions and challenge some common narratives regarding child marriage.

Conclusions

There are many reasons to be concerned about child marriage. However, evidence that child marriage causes the health outcomes described in this review is severely limited. There is more heterogeneity in the results of these studies than is often recognized. For these reasons, greater caution is warranted when discussing the potential impact of child marriage on health. We provide suggestions for avoiding common biases and improving the strength of the evidence on this subject.

Trial registration

The protocol of this systematic review was registered with PROSPERO (CRD42020182652) in May 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-12707-x.

Ethnicity and fertility in Nigeria

Using a sample of Hausa-Fulani, Yoruba, Ibo, and all other women from the 1990 Nigerian Demographic and Health Survey, this study examines ethnic fertility differentials in Nigeria within the context of the social characteristics and cultural hypotheses. Among all women, we find the net fertility of Hausa-Fulani women to be lower than that of Other women; with no statistically significant difference in the net fertility of Ibo, Yourba, and Other women. But, among currently married women, we find the net fertility of Hausa-Fulani and Yoruba women to be lower than that of Other women, while the net fertility of Ibo women is higher than that of Other women. Overall, the findings of this study are more consistent with the cultural hypothesis, because statistically significant fertility differentials by ethnicity remain, even after controlling for selected socioeconomic and demographic variables.

Determinants of contraceptive use in Morocco: stopping behaviour in traditional populations

The determinants of modern contraceptive use in traditional populations are analysed in married women aged 30-44 living in the province of Marrakech (Morocco). Women who have never used contraception have smaller family sizes than those who do: the number of live children (or live births) is the variable with maximum predictive power on contraceptive use, while child mortality is the main inhibiting factor. The probability of contraceptive use increases with female age at marriage and decreases with the woman's age, indicating a generational change in reproductive behaviour. The socioeconomic variables education, employment and residence, have no significant independent predictive character on contraceptive use, although the interaction between education and residence does. The paper evaluates the hypothesis that traditional populations in the initial phase of their demographic transition resort to modern contraception in order to stop childbearing, when they have reached a desired number of children, rather than to space births or reduce their fertility.

Marriage, age at last birth and fertility in a traditional Moroccan population

A sample of 842 rural women from Morocco (Amizmiz, Marrakech) was used to examine the relationship between a number of biosocial variables and fertility patterns. For women still in their reproductive years there were significant correlations between family size and woman's age, age at marriage and years of marriage. Among women with completed families, those with early age at marriage ceased childbearing about 10 years before reaching menopause, while women who married later continued to bear children until the end of their fertile life.