Impact of antidepressant use, discontinuation, and dosage modification on maternal depression during pregnancy.

Women tend to discontinue their antidepressants during pregnancy. This study compared the risk of depressive symptoms in the second-half of pregnancy in women who discontinue or continue with or without dosage modification their antidepressant during gestation. Women were eligible if they called MothertoBaby during 2006-2010 and within 14 completed weeks of pregnancy. A total of 367 pregnant women were included. The Edinburgh Postnatal Depression Scale (EPDS) was used to measure depression during the first and second half of pregnancy. Presence of depressive symptoms was defined as EPDS ≥13. Among participants, 149 did not use antidepressants, 38 used antidepressants at the beginning of pregnancy but discontinued before the end of second-trimester, and 180 used antidepressants continuously throughout pregnancy. Among continued users, 46 modified antidepressant dosage before the end of the second trimester, and 134 did not modify dosage. The majority of antidepressant users (150/218, 68.8%) had mild to moderate depression. Thirteen percent (13%) of women who continued antidepressant use throughout pregnancy without dosage modification remained depressed. Adjusting for potential confounders including maternal depression/anxiety before pregnancy, and compared to non-users, discontinued users were 5.95 times (95%CI: 1.54-23.02), and continued users without dosage modification 4.59 times (95%CI: 1.44-14.64) more at risk of depression in the second-half of pregnancy. Those with dosage modifications were at a similar risk of depression during pregnancy than non-users (adjusted odds ratio 0.58, 95%CI: 0.06-5.52). In conclusion, in a cohort of mild to moderate depressive pregnant women, discontinuing or continuing antidepressant use without dosage modification during pregnancy were associated with an increased risk of depression during the remaining gestational period.