Olfactory Sensitivity Show Postpartum Depression is Different to Major Depression

Summary: Women with postpartum depression report normal olfactory sensitivity, while those who are genetically predisposed to major depressive disorder have decreased olfactory sensitivity.

Source: University of Otago

Women with postpartum depression experience smell differently to other women, a University of Otago study has found.

Lead author Dr Mei Peng, of the Department of Food Science, says the findings add further evidence to the growing argument postpartum depression is different to major depression, and requires separate research and medical attention.

“Postpartum depression has been long regarded as a sub-category of major depressive disorder. This condition has a very poor diagnostic rate, with many women suffering from it without being properly diagnosed or treated.

“Recently, the scientific community has been questioning whether postpartum depression should be studied and treated separately from major depression following insights into the different effect each disorder has on neurobiology,” she says.

Pregnancy-related depression is very common, with 6–12 percent of women being affected during pregnancy, and more than 20 percent being affected after having a baby. Resolving the status of postpartum depression may have important implications for diagnosis, treatment, policy and research of the disorder.

“Our world-first study helps show the sensory symptoms related to postpartum depression are very different from those of major depression. Specifically, patients with postpartum depression show normal olfactory sensitivity whereas generic depressed patients would show substantially declined olfactory sensitivity.”

This shows a depressed looking lady
The researchers found no difference between the two groups in terms of their ability to detect smells, but postpartum depressed women experienced different intensity and hedonic perception of some smells. Image is in the public domain

The multi-disciplinary study, published in Scientific Reports, assessed the olfactory abilities of 39 depressed mothers, who were pregnant and up to one-year post pregnancy, comparing them against a healthy cohort.

The researchers found no difference between the two groups in terms of their ability to detect smells, but postpartum depressed women experienced different intensity and hedonic perception of some smells.

“These findings imply that postpartum depression is associated with alterations in higher-order olfactory perception, but not early-processing of odours.”

The researchers are currently seeking funding to further study the effects of pregnancy on women’s long-term quality of life.

About this depression research news

Source: University of Otago
Contact: Mei Peng – University of Otago
Image: The image is in the public domain

Original Research: Open access.
Olfactory shifts linked to postpartum depression” by Mei Peng, Hazel Potterton, Joanna Ting Wai Chu & Paul Glue. Scientific Reports


Olfactory shifts linked to postpartum depression

Postpartum Depression (PPD) is the most common non-obstetric complications associated with childbearing, but currently has poor diagnostic regimes. Sensory symptoms of PPD are understudied, particularly with regard to the sense of olfaction.

The present study addresses this research gap by assessing differences in olfactory abilities between 39 depressed mothers, who were within the perinatal period (i.e., during pregnancy and up to 1-year post pregnancy) and assessed with Edinburgh Postnatal Depression Scale, and their case-matched healthy volunteers.

The assessments include two olfactory testing sessions conducted 4-weeks apart, each comprising a standard odour detection threshold test (i.e., Snap & Sniff Olfactory Test System), and intensity and valence ratings for 3 “pleasant” and 3 “unpleasant” odorants.

The results revealed no difference between patients (M = 5.6; SE = 0.3) and control group (M = 5.7; SE = 0.4) in terms of olfactory detection threshold. However, the patients group perceived the 3 “unpleasant” odours as significantly less pleasant (p < 0.05), and 2 odorants (1 “pleasant” and 1 “unpleasant”) as less intense. Additionally, these results did not appear to be significantly interacted with the individual’s perinatal stage.

The present study is the first to evaluate associations between olfactory function and PPD. Findings from the study suggest that, while PPD has little effect on the early stages of olfactory processing, these conditions may have stronger influence on higher-order olfactory perception, including both hedonic and intensity perception.

These novel findings add knowledge to sensory symptoms of PPD.

Join our Newsletter
I agree to have my personal information transferred to AWeber for Neuroscience Newsletter ( more information )
Sign up to receive our recent neuroscience headlines and summaries sent to your email once a day, totally free.
We hate spam and only use your email to contact you about newsletters. You can cancel your subscription any time.