Kabul: Despite the efforts of the government and rights groups, the engagement and marriage of children still persists in Afganistan, especially among poor, uneducated families or in the countryside.

About 16 percent of Afghan children are married under the age of 15, according to recent data from UNICEF. And there is evidence that the poverty of recent years is pushing down the marriage age further in some areas.

The practice can force couples into a miserable union and sometimes expose the girl to violence if she resists In an unhappy forced marriage, the man can take a woman he loves as a second wife in Islamic and Afghan culture.

But the girls are trapped. Some commit suicide in Kapisa province, just north of Kabul, an 18-year-old girl shot and killed herself because her family would not break off her three-year engagement to a drug addict, Afghanistan's Pajhwok News Agency reported in August. Others run away, sometimes falling into drugs or prostitution.

The minimum legal age of marriage in Afghanistan is 16 for girls and 18 for boys. Yet child marriages account for 43 percent of all marriages, according to the United Nations.

The reasons are often economic: The girl's family gets a ''bride price'' of double the per capita income for a year or more, according to the World Bank.

In March, the women's ministry and rights group Medica Mondiale started a campaign to encourage marriage registration before a judge, which they hope will cut down on forced and child marriages. Marriage registration is already mandated but rarely practiced.

Many engaged couples do not meet until after they are married. In some cases, two pregnant women either sisters or good friends agree to make a match if one has a boy and the other a girl.