It should be no surprise that many women complain of disrupted sleep during pregnancy.  According to a recent study, approximately 28%-38% of women meet criteria for sleep deficiency during early pregnancy. (Sleep deficiency is defined as short sleep duration, insufficient sleep, or insomnia).As pregnancy progresses, sleep quality continues to deteriorate; during the third trimester, over half of all women report poor quality of sleep. 

While some might consider that sleep disturbance is an unfortunate consequence of pregnancy and does not require any intervention, others hypothesize that poor sleep quality during pregnancy may be associated with other problems and therefore should be identified and managed.  Concerning are the preliminary studies which suggest that poor quality of sleep during pregnancy may be associated with more depressive symptoms during pregnancy and the postpartum period.

In a recent study, sleep data was collected using diary and actigraphy during early pregnancy at 10-12, 14-16, and 18-20 weeks of gestation.  Women who were sleep-deficient across all time points reported more perceived stress than those who were not sleep-deficient. Depressive symptoms were the highest among women reporting deficient sleep across all time points.

Sleep problems emerging during pregnancy may persist after delivery, and recent work suggests that sleep disruption during and after pregnancy may contribute to the development of postpartum mood disorders (Ross et 2005 Dorheim et al 2009 Bei et al 2010 Okun et al 2009).

A small study has investigated the effect of insomnia treatment during the third trimester of pregnancy on the subsequent development of postpartum depression (PPD). Subjects were randomized to receive trazodone (an antidepressant medication with sedative effects), diphenhydramine (Benadryl, an antihistamine with sedative properties), or placebo in order to determine whether these interventions reduce the risk of postpartum depressive symptoms. The findings of this clinical trial are as follows:

·         Sleep efficacy and total sleep time improved in women treated with trazodone and diphenhydramine as compared to women receiving placebo.

·         Trazodone and diphenhydramine treatment during the third trimester of pregnancy reduced the severity of PPD symptoms (assessed at 2 and 6 weeks after delivery).

·         Sleep quality and depressive symptoms did not differ between trazodone and diphenhydramine groups.

This was a relatively small study (54 women) and warrants replication using a larger sample; however, it highlights the important relationship between sleep and perinatal depression.  While this study uses pharmacologic treatments to manage sleep problems, other non-pharmacologic interventions, such as cognitive behavioral therapy, may also be useful in this setting for women who may be concerned about exposure to medication during pregnancy.

Undoubtedly the interplay between sleep and depressive symptoms is quite complex.  Does sleep disruption cause depression?  Or is sleep disturbance merely one symptom of a depressive illness?  The really exciting finding in this study is that improving sleep during pregnancy can reduce the risk of postpartum depression.

It should be noted, however, that women with a history of sleep or mood disorders prior to their pregnancy, as well as women with any previous antidepressant use, were excluded from this study.  We do not know, therefore, whether women who present with sleep disturbance in the context of a depressive episode will respond to these sorts of sleep interventions as well as women with only sleep disturbance.

Ruta Nonacs, MD PhD

Okun ML, Kline CE, Roberts JM, Wettlaufer B, Glover K, Hall M.  Prevalence of sleep deficiency in early gestation and its associations with stress and depressive symptoms.  J Womens Health (Larchmt). 2013; 22(12):1028-37.

Coo S, Milgrom J, Trinder J.  Mood and Objective and Subjective Measures of Sleep During Late Pregnancy and the Postpartum Period.  Behav Sleep Med. 2013 Oct 15. [Epub ahead of print]

Khazaie H, Ghadami MR, Knight DC, Emamian F, Tahmasian M.  Insomnia treatment in the third trimester of pregnancy reduces postpartum depression symptoms: a randomized clinical trial.  Psychiatry Res. 2013; 210(3):901-5.