Breastfeeding and later maternal depression and anxiety with Fionnuala McAuliffe

A 10-year prospective cohort study published in BMJ Open found that breastfeeding may be associated with lower rates of depression and anxiety later in women’s reproductive lives, extending beyond the well-documented benefits seen in the postpartum period. The findings add to growing evidence that breastfeeding may confer long-term mental health benefits for mothers, particularly when sustained over longer durations.

The study followed 168 parous women from the ROLO Longitudinal Cohort in Dublin, Ireland, tracking lifetime breastfeeding behavior and self-reported mental health outcomes over a decade. The mean age of participants at the final follow-up was 42.4 years, placing the cohort in midlife, a period when anxiety and depression often emerge or recur. Among participants, 72.6% reported ever breastfeeding, and 37.5% breastfed for a cumulative duration of at least 12 months across their lifetime.

At the 10-year follow-up, 13.1% of women reported depression or anxiety, while 20.8% reported these conditions at any point during the study period. Ever breastfeeding was associated with lower odds of depression or anxiety at 10 years (OR, 0.34; 95% CI, 0.12–0.94 [P = 0.04]), and similar protective associations were observed across the full study period. Longer exclusive breastfeeding and lifetime breastfeeding of 12 months or more were also associated with reduced odds of depression and anxiety, demonstrating a clear dose–response relationship ever breastfeeding OR 0.4, [P = 0.03]; exclusive breastfeeding OR 0.98/week, [P = 0.03]; lifetime breastfeeding ≥12 months OR 0.38, [P = 0.04]) .

“Everyone is aware, of course, that breastfeeding has many benefits for the baby,” said Fionnuala McAuliffe, MD, FRCOG, Chair and Full Academic Professor of Obstetrics & Gynaecology at University College Dublin and study investigator. “But there’s increasing interest in the benefits to the mother for breastfeeding We recruited women in early pregnancy and have had the opportunity to follow them regularly throughout the years. At the 10-year time point, we asked the mothers about detailed information about their lifetime breastfeeding experience… and then we asked information about their health.”

Importantly, the cohort was initially composed of healthy women without preexisting medical or mental health conditions. “They weren’t on medication,” McAuliffe noted. “So they were a particularly healthy group… representative of a healthy group of women.”

“Those that breastfed had much lower rates, about half the rates,” McAuliffe said. “And then we were very excited to see a dose–response effect. So the longer she breastfed for, the stronger the relationship was.”

McAuliffe hypothesized that the association may stem from breastfeeding’s known protective effect against postnatal depression. “We know that postnatal depression can alter the functioning of the brain,” she said. “So we’re hypothesizing that those benefits accrue in the longer term.”

She emphasized that the findings reinforce the importance of sustained breastfeeding support.

“Breastfeeding is free. It’s available to everybody,” McAuliffe said. “The idea that there could be some long-term additional health benefits to her, particularly in the area of mental well-being, is very exciting and another reason for us to support women to breastfeed, if that’s what their choice is.”

Reference:

McNestry C, O’Reilly SL, Twomey PJ, et al. Breastfeeding and later depression and anxiety in mothers in Ireland: a 10-year prospective observational study. BMJ Open. 2026;16:e097323. doi:10.1136/bmjopen-2024-097323