MUNICH – Children born to mothers who had fertility problems had a 33% increased incidence of psychiatric disorders as children or young adults, compared with the offspring from mothers without fertility problems, a population-based Danish study found.
While clinicians and patients should be aware of this "modest" increased risk, it should be "balanced against the physical and psychological benefits of pregnancy," Allan Jensen, Ph.D., said at the annual meeting of the European Society of Human Reproduction and Embryology.
"I think this is an acceptable risk" from the perspective of both individual women and society, said Dr. Jensen, a senior researcher at the Danish Cancer Society Research Center in Copenhagen. The findings "should not discourage women from receiving fertility treatment," he said in an interview. "I think this is a small risk."
Dr. Jensen estimated that about 2% of psychiatric disorders that exist today among Danish children and adults are attributable to mothers who underwent fertility treatment. Although his study has not yet analyzed whether any specific treatments used during assisted reproduction seemed to link with subsequent psychiatric disorders in offspring, he speculated that the primary mechanism is likely defective genes carried by women with fertility problems.
The Danish infertility cohort contained information on more than 109,000 women who underwent a fertility consultation from 1963 to 2009, and these data were used along with Danish birth records starting from 1969 and Danish national medical records for psychiatric disorders that also dated from 1969. The analysis identified 7,860 children or adults who had received a psychiatric diagnosis and were born to women treated for fertility problems.
Results from a multivariate, regression analysis that controlled for year of birth, maternal age at birth, sex, and birth order, showed that children of mothers who had received fertility treatment had a statistically significant, 33% increased rate of having a psychiatric disorder, compared with people born to mothers without a fertility problem.
Additional analysis showed statistically significant increases across a broad swath of psychiatric disorders. For example, children born to mothers who had fertility treatment had a 47% higher rate of attention-deficit/hyperactivity disorder, a 43% higher rate of personality and behavior disorders, a 32% increase in affective disorders, a 28% higher rate of mental retardation, a 27% higher rate of schizophrenia, and a 12% higher rate of autism-spectrum disorders.
The analysis did not adjust for fertility treatment the women received or for child factors such as birth weight and prematurity. But the analysis did find that a statistically increased rate of various psychiatric disorders existed independently in both children and in young adults.
The study had the advantages of using the largest population ever examined for this issue, including a long follow-up, and avoiding selection bias or recall bias by being population- and registry-based, with virtually complete ascertainment of psychiatric cases. It had the shortcoming of being unable to distinguish cause from infertility in the women or from the treatments they received, Dr. Jensen said.
Dr. Jensen said that he had no disclosures.
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