When we meet women for consultations regarding the use of psychotropic medications during pregnancy, we focus primarily on the impact of medications on the developing fetus and the pregnancy.  However, we need also to address the impact of psychiatric illness in the mother on the pregnancy.  In studies of pregnant women with unipolar depression, it has been shown that untreated psychiatric illness in the mother may have a negative impact on pregnancy outcomes, influencing the length of gestation and birthweight.  There is far less data on pregnancy outcomes in women with bipolar disorder.  A recent study reviews and analyzes pregnancy outcomes in women with bipolar disorder.

In this report, researchers reviewed published studies which included women with a diagnosis of bipolar disorder prior to pregnancy who were pregnant and/or followed for one year after childbirth. Their initial search identified 2809 papers; after screening and quality assessment (using the EPHPP and AMSTAR tools), nine papers were selected and included in the final analysis.  All maternal or infant outcomes were examined. Because there was considerable heterogeneity in the studies analyzed, the authors presented the data in a narrative form.  When possible, meta-analysis was used to estimate prevalence for some outcomes.   

The researchers found that adverse pregnancy outcomes, including gestational hypertension, antepartum haemorrhage, and placenta previa, occurred more frequently in women with bipolar disorder. Women with bipolar disorder also had increased rates of induction of labor and caesarean section.   Furthermore, women with bipolar disorder were more likely to have babies that were severely small for gestational age (< 2nd-3rd percentile).  

The clearest finding in this meta-analysis was that women with bipolar disorder were at increased risk for psychiatric illness during pregnancy and the postpartum period.  During pregnancy, rates of mood episodes varied across the studies from 9 to 18%. Mood episodes were more common during the postpartum period ranging from 25 to 79%.

I was hopeful that in this analysis the researchers would be able to analyze the data in order to  distinguish between the effects of medication versus the effects of untreated psychiatric illness in the mother; however, the numbers were small and the studies so heterogeneous that they were not able to conduct this sort of analysis.  Thus far only one study has attempted to distinguish between exposure to medication versus exposure to maternal illness within this bipolar population.

In this study, Boden and colleagues analyzed pregnancy outcomes in women with bipolar disorder and concluded that bipolar disorder in women, whether treated with medication or not, was associated with worse pregnancy outcomes.  The study suggests that while exposure to mood stabilizers during pregnancy may carry some risk, this exposure to medication is not the sole reason for adverse pregnancy outcomes in women with bipolar disorder, and it is important to note that the illness itself– or behaviors associated with having the illness– may also have a negative effect on pregnancy outcomes

When counseling women with bipolar disorder who are pregnant or planning to conceive, we must focus on optimizing treatment during pregnancy, acknowledging that the avoidance of all medications is not necessarily the safest option.  Women planning a pregnancy must be properly counseled regarding the risks of treatment versus the risks associated with the untreated psychiatric illness in the mother, and the woman’s health care provider plays an important role in weighing these individual risks and selecting the best options for treatment.

Ruta Nonacs, MD PhD

 

Boden R et al. Risks of adverse pregnancy and birth outcomes in women treated or not treated with mood stabilisers for bipolar disorder: Population based cohort study. BMJ 2012; 345:e7085.

Rusner M, Berg M, Begley C.  Bipolar disorder in pregnancy and childbirth: a systematic review of outcomes.  BMC Pregnancy Childbirth. 2016 Oct 28;16(1):331.  Full Text Article