Maternal bipolar disorder increased low birthweight and preterm births: a nationwide population-based study

To investigate pregnancy outcomes, including low birthweight, preterm births, and small-for-gestational-age (SGA) among women with bipolar disorder, schizophrenia compared with women with no history of mental illness using nationwide population-based data.

This study linked the Taiwan National Health Insurance Research Dataset with the national birth certificate registry. A total of 528,398 singleton births between 2001 and 2003 were included; 337 were diagnosed with bipolar disorder. Multivariate logistic regression analyses were carried out to examine the relationship between maternal bipolar disorder, schizophrenia and the odds of low birthweight, preterm births, and SGA, after adjusting for characteristics of infant, mother and father.

It shows that pregnant women with bipolar disorder were more likely to have LBW infants (9.8% vs. 5.7%), preterm births (14.2% vs. 6.9%) and SGA (22.3% vs. 15.7%) than pregnant women with no history of mental illness. The adjusted odds of low birthweight for women with bipolar disorder was 1.66 times (95% CI, 1.16-2.38) that of women with no history of mental illness. In terms of preterm births and SGA, the adjusted odds ratios were 2.08 (95% CI, 1.53-2.83) and 1.47 (95% CI, 1.14-1.91) respectively, for women with bipolar disorder, compared to their counterparts with no history of mental illness.

We conclude that women with bipolar disorder had increased risk of low birthweight, preterm births, and SGA than women without a history of mental illness. More active monitoring and early intervention to counter potential adverse pregnancy outcomes for pregnant women with bipolar disorder should be initiated.