WEDNESDAY, July 27 (HealthDay News) -- Young children born after unplanned pregnancies tend to have a smaller vocabulary and poorer non-verbal and spatial abilities than other children, but these problems are actually due to socioeconomic factors, a new study suggests.

Researchers led by Claire Carson of the University of Oxford looked at data from about 12,000 children who took part in a large U.K. study of infants born from 2000 to 2002. Their parents were interviewed when the children were 9 months old, 3 years old and 5 years old. The children's verbal, non-verbal and spatial abilities were tested at ages 3 and 5.

Children born after an unplanned pregnancy were four to five months behind children of planned pregnancies in verbal abilities, the researchers found, but these differences virtually disappeared when the researchers factored in the children's socioeconomic circumstances.

"These differences are almost entirely explained by socioeconomic factors," the researchers concluded.

They also found that mothers' infertility treatments have no effect on children's cognitive development when they are 3 and 5 years old.

The study was published online July 27 in the BMJ.

More information

The U.S. Centers for Disease Control and Prevention has more about child development.