Do women who breastfeed experience less stress than women who formula-feed?

Last updated: February 20, 2022
The single study in this list that examines this question found that the answer is yes. A single study is often not sufficient to draw a conclusion so we encourage you to refer to this study merely as food for thought.

Chart summary of 1 study examining this question

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Literature Reviews
Although we recommend you consider all of the studies below, we believe the following study is a literature review, which surveys and evaluates many studies on this question:

Total studies in list: 1
Sorted by publication year
Psychological effects of breastfeeding on children and mothers
"Breastfeeding has been reported to impact mood and stress reactivity in mothers [55]. Specifically, breastfeeding mothers report reductions in anxiety, negative mood, and stress when compared to formula-feeding mothers [56]. These findings based on subjective self-report measures are supported by objective physiological measures indicative of a positive effect of breastfeeding on emotional well-being. For example, breastfeeding mothers have stronger cardiac vagal tone modulation, reduced blood pressure, and reduced heart rate reactivity than formula-feeding mothers have, indexing a calm and non-anxious physiological state [57, 58]. Moreover, there is evidence to show that breastfeeding mothers have a reduced cortisol response when faced with social stress [55]. Breastfeeding mothers also display prolonged and higher quality sleep patterns than those who feed their infants formula. Specifically, there is research to show that at 3 months postpartum, breastfeeding was associated with an increase of about 45 minutes in sleep and reduced sleep disturbance [59]. Critically, breastfeeding also impacts mothers’ responses to emotions in others and may thereby improve social interactions and relationships. More specifically, recent work shows that prolonged durations of exclusive breastfeeding are linked to facilitated responses to inviting (happy) facial expressions and that more frequent breastfeeding on a given day is linked with reduced responsivity to threatening (angry) facial expressions [60].In summary, there is research showing that breastfeeding has beneficial effects on mothers’ own mood, affect, and stress, and also that breastfeeding facilitates responses to positive emotions in others. Similar effects on affect and stress as seen here for breastfeeding are also observed in studies administering oxytocin intranasally compared to a placebo [61, 62], suggesting that breastfeeding may affect (increase) endogenous oxytocin levels in the mothers. This is in line with the known role of oxytocin during breastfeeding and supported by research documenting a rise in maternal oxytocin levels during breastfeeding [63]. More evidence in support of this notion comes from a recent study which revealed that mothers’ genetic variation in oxytocin (as indexed through the CD38 rs3796863 SNP) impacts the rate at which cortisol decreases during a breastfeeding session. Specifically, mothers with the non-risk genotype, associated with higher oxytocin levels, showed a steeper reduction in cortisol. Strikingly, this differential reduction in cortisol was found in their infants as well [64]. It is thus likely that the positive effects of breastfeeding on the measures reviewed above have a physiological basis in an upregulation of endogenous oxytocin levels among breastfeeding mothers."
Kathleen M. Krol
2018 Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz volume
Literature Review