The analysis, titled "Covid-19: A threat to progress against child marriage", released on Monday warns that school closures, economic stress, service disruptions, pregnancy, and parental deaths due to the pandemic are putting the most vulnerable girls at increased risk of child marriage, reports Xinhua news agency.
Even before the pandemic began, 100 million girls were at risk of child marriage in the next decade, despite significant reductions in several countries in recent years.
In the last 10 years, the proportion of young women globally who were married as children had decreased by 15 per cent, from nearly one in four to one in five, the equivalent of some 25 million marriages averted, a gain that is now under threat, according to the analysis.
Girls who marry in childhood face immediate and lifelong consequences, the analysis said, adding that they are more likely to experience domestic violence and less likely to remain in school.
Child marriage also increases the risk of early and unplanned pregnancy, in turn increasing the risk of maternal complications and mortality. The practice can also isolate girls from family and friends and exclude them from participating in their communities, taking a heavy toll on their mental health and well-being.
As schools remain closed, girls are more likely to drop out of education and not return. Job losses and increased economic insecurity may also force families to marry their daughters to ease financial burdens.
Worldwide, an estimated 650 million girls and women alive today were married in childhood, with about half of those occurring in Bangladesh, Brazil, Ethiopia, India and Nigeria.
"Covid-19 has made an already difficult situation for millions of girls even worse. Shuttered schools, isolation from friends and support networks, and rising poverty have added fuel to a fire the world was already struggling to put out. But we can and we must extinguish child marriage," Unicef Executive Director Henrietta Fore said.
"One year into the pandemic, immediate action is needed to mitigate the toll on girls and their families."