Children conceived artificially don’t have worse cognitive skills than babies conceived naturally. In fact, kids born through techniques such as in vitro fertilization (IVF), or intracytoplasmic sperm injection (ICSI), had better scores on reading and verbal tests, according to a new study.

Despite some prior research suggesting in vitro fertilization and other assisted reproductive technologies (ART) can harm a child’s cognitive ability, researchers at the University of Oxford found otherwise. They also found that parents who undergo IVF and ICSI are typically older, more educated, and have a higher income than parents who had naturally conceived children. ICSI is a variation of the IVF technique and is used for various situations including when the man has a very low sperm count or previous IVF attempts have been unsuccessful.

Research has shown that babies born through various reproductive technologies are more likely to be part of a multiple birth or have low birth weight.

Read: Pregnancy After 40: Artificial Reproductive Technologies Like IVF May Reduce Birth Defect Risk

“The findings suggest that the positive effect of the family background of children conceived through artificial reproduction techniques ‘overrides’ the risks of related poor health impairing their cognitive ability,” study author Melinda Mills said in a news release.

In the study, published in the journal Human Reproduction, Mills and colleagues looked at data from the Millennium Cohort Study, which continues to follow the lives of more than 18,500 children born in the U.K. in 2000 and 2001. Children were given cognitive ability tests at various points in their lives from ages 3 to 11 years, which assessed vocabulary skills, reading, and use of verbs. The final sample of artificially conceived children in Mills' study included 125 born through IVF and 61 conceived through ICSI. The test scores of the children born through ART were compared to children who were conceived naturally.

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Analyses revealed that ART didn’t impair a child’s higher thinking skills. At age 3 and 5 years, children conceived with the aid of ART had higher scores on verbal cognitive tests. Over time, this decreased and leveled off by age 11. Once the children reach 11 years old, the role of the parents is especially important for cognitive development, the authors note in their paper.

“Parents may perceive their children as more fragile but once past the period of greatest risk, their parenting style may change to become more like other parents,” lead author Anna Barbuscia said. “This might account for the fact that the gap in higher cognitive ability has closed by the time both groups of children had reached the age of 11 with only slightly better scores for artificially conceived children at this later stage.”

One of the limitations of this study is the sample size of ART children was much smaller than the number of naturally conceived children. Due to the limited sample sizes, the researchers could not compare IVF to ICSI treatment, they note.

Today, many people have heard of IVF, despite it being a fairly new procedure. The first-ever IVF baby was born in England in 1978. Three years later, the first was born in the United States. As of 2015, about 1.6 percent of all infants born in the U.S. every year are conceived using ART, according to the Centers for Disease Control and Prevention.

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