Assisted Reproduction Technology Thwarts Physical Development of Kids

Main Category: Fertility
Article Date: 14 Feb 2005 - 23:00 PDT


Twins conceived via assisted reproduction technology tend to be smaller at birth than those who are naturally conceived. And while the size differential disappears by the age of two, they remain less physically developed in other ways than their traditionally conceived peers at that age.

That is the conclusion of a recent study co-authored by Kristine Anthis, an assistant psychology professor at Southern Connecticut State University. The study was published recently in the Journal of Genetic Psychology. Lisa Kelly-Vance, an associate professor of psychology at the University of Nebraska, co-authored the paper with Anthis, while they were assisted by Dr. Howard Needelman, a pediatrician with the Munroe-Meyer Institute at the University of Nebraska Medical Center and Children's Hospital. Most of the research was conducted while Anthis was a graduate student at the University of Nebraska-Omaha.

While the use of assisted reproduction has been increasing rapidly in recent years, research in this area has been relatively sparse, according to Anthis. And the studies that have been conducted have produced inconsistent findings. Among the types of assisted reproduction used today are in vitro fertilization and various types of fertility drugs.

The study showed that the average weight of a twin baby whose conception was assisted was about three-quarters of a naturally conceived twin baby. That difference evaporated by the time both were two years old. But the physical development index - which includes such criteria as body control, coordination and fine motor skills -- continued to show a significant difference at the age of two. The index found that assisted babies were at about an 85-percent level of the others.

"We were surprised with the findings," Anthis said. "Some differences between babies of spontaneous conception and assisted conception had been found in past research projects, but they compared apples with oranges. That is, assisted reproduction tends to produce a higher percentage of twins than spontaneous conception does. Prior studies often had a larger number of twins in the assisted reproduction group than in the spontaneous conception group. And since twins, in general, tend to have lower birth weights, the groups being compared had not been equivalent.

"So, we thought that those differences would disappear in this study because we decided only to examine twins. But there were still physical differences at two years of age between twins who were spontaneously conceived and those whose conception was induced."

Anthis noted that no mental development differences were found in the 2-year-olds. She added that she is uncertain whether physical differences will continue into childhood, or even adulthood, and what the ramifications these differences might mean for those children. She believes more studies need to be done to answer those questions.

Her study included 114 babies (57 sets of twins), of which 78 were spontaneously conceived and 36 were conceived with the assistance of reproduction technology. A subset of those babies were studied at the age of two.

Southern Connecticut State University
501 Crescent St.
New Haven, CT 06515, USA
Phone 203-392-6586
Fax 203-392-6124
http://southernct.edu

• Additional
• References
• Citations