Is Emesis a Part of Antenatal Depression? A Proposal of Emesis-Depression Complex During Pregnancy

Background: Both depression and emesis (nausea and vomiting) are commonly seen during pregnancy. The two often coexist but their symptomatic structure and causal relationships remain unclear. Aim: To identify a clinical cluster with depression and emesis together among pregnant women. Methods: Using two independent follow-up data (Study 1 with women of 10 to 13 weeks of gestation [N = initially 382 and follow-up 129] and Study 2 with women of 12 to 15 weeks of gestation [N = initially 696 and follow-up 245]) sets of pregnant women, we measured depressed mood, loss of interest and three emesis symptoms (nausea, vomiting, and retching). The samples were re-examined with an interval. Results: The 5 symptoms were substantially correlated with each other at each time point and factor analyses identified two factors reflecting depression and emesis. However, depression and emesis were associated with clinical correlates in a very similar manner. Two-step cluster analysis yielded only two clusters: one with and another without depression and emesis simultaneously. Taxometrics indicated dimensionality rather than taxonicity. Conclusion: Findings suggest that emesis and depression during pregnancy are two discrete aspects of a single clinical phenomenon that we propose to name emesis-depression complex.