In addition to dealing with mental illness themselves, depressed mothers may be disrupting their child's development. This is according to new research by Penn State University and the Los Angeles Sleep Study Institute, which found parents grappling with this condition are more likely to wake their sleeping babies.
The analysis which has been published in Child Development- has been led by Prof Douglas Teti, who found while non-depressed mothers only sought out their infants when they cried or made distressed noises, the depressed women would pick up their babies even if they only made small sounds or were in deep sleep - regardless of whether intervention was deemed necessary.
Furthermore, the research revealed depressed mums are more likely to perform inconsistent bedtime routines with their sons and daughters and are inclined to check on their sleeping children whether or not it is needed, while non-depressed mothers had calmer, more organised bedtime systems.
In response to the study, Dr Cynthia McVey, a Chartered Psychologist Glasgow Caledonian University, said: "The findings might seem surprising to some but may be indicative of the anxiety component of depression which is so often overlooked within diagnosis of depression.
"Mothers diagnosed as depressed within a year or so of giving birth, may be experiencing anxiety which is measured within depression scales. And thus the wakening of their babies may be related to the anxiety component of depression and manifested in excessive checking for the safety and wellbeing of their babies.
"Ensuring that a baby is breathing when sleeping and disturbing the baby’s rest is something most new mothers will have done from time to time. Clearly, the more anxious the mother, the more likely it is that they will check the baby more often than they should - responding to normal noises and movements as if they indicate a problem.
"Additionally, an anxious mother would likely find it difficult to produce a calming bedtime routine for a baby. If, when put to bed, the child is not at rest or sleeping and is vocal, albeit not distressed, the mother may worry that some attention is required and intervene unnecessarily.
"Of course, depressed mothers may have low self-esteem, feel inadequate and insecure about their ability to care for the baby which would also lead to anxiety and again they might exhibit similar behaviour.
"Resarch has indicated that there are three components to post natal depression - as measured by the Edinburgh Post Natal Depression Scale (EPDNS) and assessed using the Hospital Anxiety and Depression Scale (HADS) and the Positive and Negative Affect Scales (PANAS).
"These three elements, depressive symptoms, anhedonia - the lack of the ability to enjoy - and anxietal symptoms, indicate that clinicians should account for all three elements when screening for depression."