Adolescent girls at higher risk of malaria during pregnancy than adult women

Pregnant adolescents are more likely to become ill with malaria during pregnancy- or to be infected when giving birth- than adult women, according to a meta-analysis of data from more than 5,800 women in five sub-Saharan African countries. The findings of the study, led by ISGlobal, an institution supported by "la Caixa" Foundation, underline the need to develop control strategies adapted to the adolescent population.

Malaria is one of the leading causes of death in adolescent girls (aged 10-19 years). In addition, malaria during pregnancy is known to pose a risk to mother and baby. Therefore, understanding the interaction between malaria, adolescence and pregnancy is especially relevant in malaria-endemic countries, where the rate of adolescent pregnancy is high - an estimated 9 million girls between the ages of 15 and 19 become pregnant each year in Africa.

"Surprisingly, very few studies conducted in sub-Saharan Africa have compared the burden of malaria in pregnant adolescents to that in pregnant adults," says Raquel Gonzalez, ISGlobal researcher and technical coordinator of the meta-analysis clinical trials.

To do so, the team led by Clara Menéndez, director of ISGlobal's Maternal, Child and Reproductive Health Initiative, analysed data from 5,804 pregnant women who participated in two clinical trials conducted between 2009 and 2014, in five sub-Saharan countries: Benin, Gabon, Mozambique, Tanzania and Kenya. Of the total, 1,201 were adolescents (mean age 17.5 years), most of them (74%) pregnant for the first time. The rest were adult women (mean age 27 years), the vast majority of whom had already been pregnant before. Eighteen percent of the participants were HIV-positive. All had monthly antenatal visits and one postnatal visit.

The analysis shows that adolescent girls are 1.7 times more likely to become ill with malaria during pregnancy, and are at increased risk of being infected at the time of delivery. The same trend was observed for both the HIV-infected and uninfected groups. "This is the first study to disaggregate data by HIV infection status," explains Clara Pons-Duran, first author of the study.

The authors caution that the study has certain limitations, such as the small sample size in some countries and the lack of data to assess the effects of malaria on maternal and infant health. "We need more research on the consequences of malaria in pregnant adolescents," notes Raquel Gonzalez. Still, the findings underscore the need to dedicate efforts to prevent pregnancy in adolescents living in regions with malaria, and to ensure that they have access to the adquate information and tools to avoid contracting the disease in case of pregnancy.

Reference

Pons-Duran C, Mombo-Ngoma G, Macete E. Burden of malaria in pregnancy among adolescent girls compared to adult women in 5 sub-Saharan African countries: A secondary individual participant data meta-analysis of 2 clinical trials. Plos Med. 2022. Sep 2;19(9):e1004084. doi: 10.1371/journal.pmed.1004084