Pregnancy outcome of women using atypical antipsychotic drugs: A prospective comparative study.
McKenna K1, Koren G1,2, Tetelbaum M1, Wilton L3, Shakir SAW3,
Diav-Citrin O4, Levinson A5, Zipursky RB5 and Einarson A1.
1Motherisk Program, The Hospital for Sick Children, Toronto, Ontario, Canada
2Canadian Institutes of Health Research, Ottawa, Ontario, Canada
3Drug Safety Research Unit, Bursledon Hall, Southampton, SO31 1AA, UK
4Israeli Teratogen Information Service, Jerusalem, Israel
5Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
Summary/Abstract
Background
A substantial number of women of childbearing age suffer from schizophrenia and other mental illnesses that require the use of antipsychotic drugs. Atypical
antipsychotics have been on the market since the mid-1990s, and to date there are no prospective comparative studies regarding use during pregnancy.
Objectives
(1) To determine whether atypical antipsychotics increase the rate of major malformations above the 1% to 3% baseline risk seen in the general population. (2) To
examine rates of spontaneous and therapeutic abortions, rates of stillbirths, birth weight, and gestational age at birth.
Method
The cohort was composed of pregnant women who contacted the Motherisk Program in Canada or the Israeli Teratogen Information Service in Israel and women
who were recruited from the Drug Safety Research Unit database in England. Women who had been exposed to atypical antipsychotics were matched to a comparison
group of pregnant women who had not been exposed to these agents.
Results
Data were obtained on 151 pregnancy outcomes that included exposure to olanzapine (N=60), risperidone (N=49), quetiapine, (N=36), and clozapine (N=6). Among
women exposed to an atypical antipsychotic, there were 110 live births (72.8%), 22 spontaneous abortions (14.5%), 15 therapeutic abortions (9.9%), and 4 stillbirths
(2.6%). Among babies of women in this group, there was 1 major malformation (0.9%), and the mean ± SD birth weight was 3341 ± 685g. There were no statistically
significant differences in any of the pregnancy outcomes of interest between the exposed and comparison groups, with the exceptions of the rate of low birth weight,
which was 10% in exposed babies compared with 2% in the comparison group (p=.05), and the rate of therapeutic abortions (p= .003).
Conclusion
These results suggest that atypical antipsychotics do not appear to be associated with an increased risk for major malformations.
