Given the rapidly increasing use of stimulant medications during pregnancy and among women of reproductive age who may become pregnant inadvertently, there is a need to better understand their safety.
The objective of a study was to examine the risk of congenital malformations associated with intrauterine exposure to stimulants ( Methylphenidate [ Ritalin, Concerta ] and amphetamines ), dispensed during the first trimester.
A total of 1 813 894 publicly insured pregnancies in the United States and 2 560 069 singleton pregnancies in the 5 Nordic countries ( Denmark, Finland, Iceland, Norway, and Sweden ) ending in live births were included.
The study was conducted from July 1, 2015, to March 31, 2017.
In the US data, of the 1 813 894 pregnancies evaluated, 35.0 per 1000 infants not exposed to stimulants were diagnosed as having congenital malformations, compared with 45.9 per 1000 infants for Methylphenidate and 45.4 for amphetamines.
For cardiac malformations, the risks were 12.7 ( 95% CI, 12.6-12.9 ), 18.8 ( 95% CI, 13.8-25.6 ), and 15.4 ( 95% CI, 12.5-19.0 ) per 1000 infants, respectively.
The adjusted relative risks for Methylphenidate were 1.11 ( 95% CI, 0.91-1.35 ) for any malformation and 1.28 ( 95% CI, 0.94-1.74 ) for cardiac malformations.
No increased risks were observed for amphetamines: 1.05 ( 95% CI, 0.93-1.19 ) for any malformations and 0.96 ( 95% CI, 0.78-1.19 ) for cardiac malformations.
Replication of the analyses for Methylphenidate using the Nordic data including 2 560 069 pregnancies yielded a relative risk of 1.28 ( 95% CI, 0.83-1.97 ) for cardiac malformations, resulting in a pooled estimate of 1.28 ( 95% CI, 1.00-1.64 ).
In conclusion, these findings suggest a small increase in the risk of cardiac malformations associated with intrauterine exposure to Methylphenidate but not to amphetamines.
This information is important when weighing the risks and benefits of alternative treatment strategies for attention-deficit / hyperactivity disorder in women of reproductive age and during early pregnancy. ( Xagena )
Huybrechts KF et al, JAMA Psychiatry 2017; Epub ahead of print