Fiona MacCallum told the 20th annual conference of the European Society of Human Reproduction and Embryology that this was a significant difference when compared with families with children conceived through IVF using the parents' own eggs and sperm, and with families where a child has been adopted in infancy. Over 90% of IVF parents and 100% of adoptive parents planned to tell their children about their origins.
However, the study showed that the greater secrecy did not seem to affect the children adversely, and although there was more emotional over-involvement amongst the embryo donation parents, there were no differences between them and IVF or adoptive parents in terms of parental warmth and the quality of parenting.
Ms MacCallum, a research psychologist at the Family and Child Psychology Centre, City University, London, UK, said: "The most common reasons for not telling the child about their method of creation were fears that it would upset the child or damage family relationships, and also a feeling that, since the mother carried and gave birth to the child, she was the real mother and so there was no need to tell the child anything different."
Ms MacCallum studied 21 families with a child conceived through embryo donation. Embryo donation is a process whereby surplus embryos resulting from IVF procedures are donated to infertile couples. Children conceived this way are raised by two parents with whom they share no genetic relationship, although the parents experience the mother's pregnancy and the birth of the child.
She compared them with 28 families with children adopted as babies, and 30 families with children conceived through IVF. All parents were interviewed and completed questionnaires when the children were aged between two and five.
"Embryo donation parents obtained significantly higher scores on measures of emotional over-involvement and defensive responding than did the adoptive or IVF parents. However, we found no differences between the three groups for parental warmth, the quality of the parenting, or the behavioural and emotional functioning of the children.
"For emotional over-involvement we looked at the extent to which family life and emotional functioning of the mother is centred on the child; for instance, whether the mother is happy to leave her child with other caretakers, whether the needs or desires of the child are put before those of other family members, whether the mother has interests or activities that are not child-related. This trait could produce children who are very dependent on their parents and who do not develop autonomy appropriate to their age. Also family life could become centred around the child, putting pressure on him or her.
"Defensive responding relates to the manner in which the mother responds to questioning about the child or about family life; for instance, is she trying to present a picture of a 'perfect family' or is she willing to acknowledge difficulties where they exist? This trait could produce a secretive family that does not discuss issues openly.
"Despite the higher levels of these aspects of parenting, there seemed to be no negative effects on the children conceived through embryo donation at this stage. We found no evidence of pathological emotional over-involvement and the children did not seem to be suffering any adverse consequences from this or from the increased secrecy in the family about their origins. It is possible that parents of adopted children respond less defensively than the embryo donation parents because they are used to being questioned about these matters during the adoption process."
An interesting finding from the study was the fact that there was no difference in the quality of parenting between the three groups, despite the fact that the parents in two of the groups shared no genetic relationship with their children, and the adoptive parents did not even have the experience of having given birth to their children.
"This supports the idea that it is the level of commitment to parenting that is important, and not the presence or absence of biological links between parent and children," said Ms MacCallum.
Abstract no: O-087 (Monday 17.30 hrs CET Hall 7)