Teenage girls in Sierra Leone's capital Freetown are selling their bodies to buy mobile phones, putting them at increased risk of pregnancy and sexually transmitted diseases, says a study by Save the Children.
"Mobile phones represent everything that an adolescent associates with being young, hip and fashionable. They are part and parcel of the idea of what they want to become, and to get them they engage in risky sexual behaviour," said Krystle Lai, the research author.
"Young girls are driven to seek older, richer men who can afford to buy them mobile phones, but the economic power in these relationships is unbalanced and influences the bargaining power of using a condom," added Lai, noting that Sierra Leone has poor sex education.
She said once girls own a phone, especially poorer girls, the maintenance and top up may mean they have to continue selling their bodies.
The research in Freetown appears to reflect a wider global trend. The report said there was growing evidence that the demand for mobile phones was among the key drivers for young girls in low-income countries to engage in transactional sex.
Girls in Freetown also use transactional sex to buy fashionable clothes, good exam results, known locally as "sexually transmitted grades", and even staple foods, researchers found.
The girls often have different partners to meet different needs.
"One girl at school was in love with three boys. One of them did her (school) assignments, one would buy her clothes, and the other one bought her phone and other things like money. One man won't do," one girl told researchers.
There are different types of man. The 'old pa' can be over 50 years old, the 'big man' is 25 to 50 years old and then there are the young guys - those are the ones the girls actually love, the report said.
"Many girls consider going with old men much better as they pay more money and they will only ask for oral sex instead of intercourse, so there is no chance of getting sexually transmitted diseases or becoming pregnant," Lai told Thomson Reuters Foundation by phone from Freetown.
One girl told researchers: "The 'old pa' ask ... the girls to just touch them but usually no sex. The 'big men' ask for everything, kiss, oral sex and sex."
Many adolescent girls in the study demonstrated little understanding of HIV or other health risks surrounding concurrent relationships.
Lai said worldwide data showed an increase in teenage pregnancy and sexually transmitted diseases, including HIV, due to transactional sex between girls and older men.
FORCED TO SELL VIRGINITY FOR 23 CENTS
Parents reacted differently to their daughter's behaviour, the research said. While fathers came down hard, mothers were often fully aware of their daughter's activities and chose to ignore them, or even encourage them.
"If there is nothing at home, the mother will ask the girl to go out and 'find something'. This word is very common in the community. If your mother says this, you know what she means," said one girl.
Another described how her friend lost her virginity for an onion.
"My friend dropped an onion, she didn't have the money to replace it so she had to beg from a boy. They boy gave it to her for Le 1000 ($0.23) and then asked for sex. She lost her virginity to buy an onion," she said.
Lai said poverty drove mothers to make difficult decisions. "You have to step into the shoes of a mother with four children. You are poor, you may be single, and the only way that you as a mother have seen in the past that you can make some money is by using your body.
"As a mother, you can send one child out to somehow get some money, which will have a benefit for your other three children, or you have all four of your children suffer. These are the decisions that mothers face in Freetown on a daily basis."
Lai says punishing mothers is not the answer. It's sex offenders who should be penalised.
"We need income generating activities and to teach better parenting skills to mothers, who may have been brought up by teenager mothers themselves. The cycle of parenting has been broken and it's up to civil society to try and patch things up again," Lai said.
"However, sex offences must be punished to the full extent of the law, which says anybody aged under 18 years is a child, and identifies any form of sexual relationship with a child as a offence warranting five to 15 years imprisonment."