Baby’s heart rate shows stress if their mother is depressed or anxious

Babies aged 3 months whose mothers suffer from affective disorders show physiologically stronger signs of stress than babies who have healthy mothers. This was shown in a study in which 3-month-old babies were given a standard stress test. They showed a significantly increased heart rate of an average of 8 beats per minute during the non-interactive phase; this may result in imprinted emotional stress later in life [1].

The study was performed with a group of 50 mothers and their babies. The mothers were evaluated using the Diagnostic Interview for Mental Disorders. One or more affective disorders were present in 20 mothers and the other 30 mothers were the control group. Heart rate variability of mothers and their 3-month-old infants was measured with ECG during the still-face paradigm (SFP), a 6-minute task that engages mother and child in playful and stressful situations. Moreover, the children’s behaviour was assessed subjectively by their caregivers using the infant behaviour questionnaire.

During the first 2 minutes of the SFP, the mothers were able to interact with their babies playfully, while their infants were seated on a baby-rocker. No direct physical contact was allowed during any of the 3 phases. The beginning of phase 2, the stressful phase, was signalled to the mothers by a knock on the door; during the following 2 minutes mothers were told to gaze at their infants, without making any gestures or mimics. The last phase consisted again of 2 minutes of playful interaction between mothers and their babies.

Children of mothers suffering from an affective disorder had significantly higher heart rates during the still-gaze situation (P=0.048) compared with children from mothers of the control group and were classified by their primary caregivers as having a more difficult temperament richer in negative affection (P=0.041). Furthermore, mothers in the control group had notoriously higher heart rates during all 3 phases compared with mothers with an affective disorder and the mothers´ mean heart rate differed significantly between groups (P=0.04).

These differences between infants and mothers of clinical and control groups indicated that infants with a primary caregiver suffering from an affective disorder have more difficulties learning to cope with stress, which is measurable at a young age. It was also demonstrated that mothers without an affective disorder are more active when interacting with their babies, as well as more reactive to their infant´s needs during stressful situations. These results demonstrated psychological as well as physiological consequences of negative interactions between mothers and their infants and calls for early intervention to prevent further consequences.

 

1. Blanco-Dormond F. Heart rate variability in mothers with affective disorders and their infants during the still-face-paradigma. P246. ECNP Congress 2020.

Posted on 2 November 202017 May 2024