Children born to a surrogate mother or conceived through donated sperm or a donated egg do just as well psychologically as counterparts who are naturally conceived, a study unveiled on Sunday said.
The probe is the widest yet into concerns that the rising numbers of children born through assisted reproduction may suffer lower self-esteem or be treated less positively by parents, siblings and schoolmates.
Scientists led by Polly Casey from the Centre for Family Research at Britain's Cambridge University carried out interviews and psychology tests among 39 surrogacy families, 43 donor insemination families and 46 egg donation families. The children are now seven years old.
For comparison, they made the same investigation among 70 families where the children had been conceived naturally. They also asked the children's teachers, in order to get an independent assessment of the child's wellbeing.
The children were all given a blank "map" with concentric circles, and were told that they were at the centre of it. They were asked to complete the map by placing family members and friends in the circle that represented the emotional closeness of each relationship.
They were also given a picture test, designed as a measure of self-esteem, to assess where they felt they stood among their peers.
"We found that the family types did not differ in the overall quality of the relationship between mothers and their children and fathers and their children," Casey said.
Mothers who had had their child through surrogacy and egg donation tended to be more sensitive to their child's worries and anxieties compared with donor insemination mothers and natural conception mothers, but the difference was minor, she added.
As for the child's view of family relationships, children of all backgrounds placed their mother or father in the closest circle with the same frequency.
There was no significant difference between family types when it came to self-esteem.
An overview of the research, based on data from approximately half of the families, was to be presented on Sunday at the annual conference, taking place in Barcelona, Spain, of the European Society of Human Reproduction and Embryology (ESHRE).
In a press release, Casey added that she found a majority of parents of children born through assisted reproduction delayed telling the child about how he or she was conceived.
"At the time of the child's seventh birthday, only 39 percent of egg-donation parents, 29 percent of donor-insemination parents and 89 percent of surrogacy parents had told their children about the nature of their conception."
These figures contrast markedly with what the parents said they would do when they were questioned at the child's first birthday.
At this point, 56 percent of egg-donation parents, 46 percent of donor-insemination parents and 100 percent of surrogacy parents declared they would disclose this information to the child.
The reasons for not informing the children "are numerous and complex," including a desire to protect an infertile father and the fear that a child may feel less love for the non-genetic parent, she said.