Maternal probiotic milk intake during pregnancy and breastfeeding complications in the Norwegian Mother and Child Cohort Study

Abstract

Purpose During the time of breastfeeding, a third of all women contract (or: fall ill in) mastitis—the leading cause of precocious weaning. Recent studies indicate that probiotics intake may prevent mastitis by altering the breast’s bacterial flora. The aim of this study was to examine whether probiotic milk intake during pregnancy is associated with less breastfeeding complications and longer breastfeeding duration. Methods This study included 57,134 women, with live singleton term births, participating in the Norwegian Mother and Child Cohort Study. Probiotic milk intake during the first half of pregnancy was self-reported in a validated food frequency questionnaire at gestational week 22. At 6 month postpartum, women reported complications, including mastitis, and duration and exclusivity of breastfeeding. The association between probiotic milk intake and breastfeeding complications and duration was studied by adjusted logistic regression models. Results Probiotic milk intake was associated with increased risk for mastitis [adjusted odds ratio (aOR) 1.09, 95% confidence interval (CI) 1.02–1.16] and for any breastfeeding problems during the first month (aOR 1.19, 95% CI 1.10–1.21). However, cessation of predominant (aOR 0.95, 95% CI 0.91–0.96) or any (aOR 0.79, 95% CI 0.75–0.84) breastfeeding earlier than at 4 months was less frequent in probiotic milk consumers than in non-consumers. Conclusions Even though probiotic milk intake during the first half of pregnancy was statistically associated with increased risk for breastfeeding complications, including mastitis, the association is probably not causal. Probiotics intake was namely associated with longer breastfeeding duration and there was indication of socioeconomic confounding. Further studies, i.e., large randomized-controlled trials, are needed to understand the association between probiotic intake and breastfeeding complications.

Incidence, antibiotic treatment and outcomes of lactational mastitis: Findings from The Norwegian Mother, Father and Child Cohort Study (MoBa)

“…Our finding that early‐onset mastitis is associated with premature cessation of breastfeeding is supported by a number of previous studies 9,10,32 …”

“…Our finding that early-onset mastitis is associated with premature cessation of breastfeeding is supported by a number of previous studies. 9,10,32 That said, the absolute effects of mastitis on breastfeeding outcome appear small. Our observed associations between early mastitis and poorer breastfeeding outcomes correspond to absolute reductions of 2.5% and 1.2% in terms of the number of women reporting any or predominant breastfeeding for 6 months.…”

Probiotics Supplementation during Pregnancy: Can They Exert Potential Beneficial Effects against Adverse Pregnancy Outcomes beyond Gestational Diabetes Mellitus?

“…Women in the probiotic group had a 58% lower prevalence of experiencing mastitis [ 113 ]. In addition, Karlsson et al performed a cohort survey of more than 50,000 women in Norway to determine if pregnant women receiving probiotic milk throughout gestation showed a decreased prevalence of breastfeeding problems, including mastitis [ 114 ]. The findings indicated that the consumption of probiotic milk (La-5, Bb12, and LGG) was directly associated with the prevalence of mastitis [ 114 ].…”

The preventive and therapeutic effects of probiotics on mastitis: A systematic review and meta-analysis

“…Regrettably, the experimental data have not been fully published to date. Karlsson et al [30] published a cohort study of more than 50,000 women in Norway to examine whether pregnant women taking probiotic milk during pregnancy had a decreased incidence of breastfeeding complications, including mastitis. The results showed that the intake of probiotic milk is positively correlated with the risk of mastitis incidence.…”