Many Nepalese children live in children's homes and refuges
The government in Nepal is being urged to tighten regulations surrounding the international adoption of its children.
A study suggests the current suspension of international adoptions from Nepal should continue until proper safeguards are in place.
The research was carried out by the UN Children's Fund, Unicef, and the child rights charity Terre des Hommes.
They say numerous infringements take place, including the abuse and, effectively, the sale of children.
They say only four out of every 100 children adopted remain within Nepal, despite the international ban.
According to Terre des Hommes, many children are parted from their families without the latter's proper consent, and many of those put up for adoption are described as orphans when at least one parent is alive.
The BBC's Nepal correspondent Charles Haviland says there are a large number of substandard children's homes, some of which have allowed abuse, and some homes have opened with the aim of making money from adoptions overseas.
Terre des Hommes say as many as 80% of children in institutions should be reunited with their families.
The government suspended international adoptions last year, as an increasing number of problems came to light.
Both Unicef and Terre des Hommes recommend that the international freeze on adoption remain until domestic laws are tightened up.
For instance, they suggest adoption by foreigners only be allowed if all domestic options have been exhausted, and that strict measures be enacted to prevent pressures on birth families, or inducements offered to them, to give up a child.
They say siblings are being needlessly separated when adopted, and family records carelessly destroyed, to the disappointment of Nepalese adopted abroad who later return to try to trace their relatives.