(347) Probiotics Perinatal Vertical Transmission from Mother to Neonate

Objective: Probiotics given to preterm babies can reduce the risk of perinatal complications such as necrotising enterocolitis. The primary objective was to determine if in utero vertical probiotics transmission is possible.

Study Design: A randomized double-blinded crossover pilot study was proposed to women aged 18-42 years, with a single pregnancy, considered at low risk. Probiotics (powder for dilution) containing 5 bacterial strains (FlorababyÒ) vs Placebo were offered. At 32-33 weeks of gestation (WG), women were randomized in: Group A: probiotics from the 34 WG until delivery and placebo from delivery to 10 days post-partum (D PP) or group B: placebo from the 34 WG until delivery then probiotics from delivery to 10D PP. All women completed questionnaires and a logbook to assess compliance and side effects. Samples were collected at baseline and at 37 WG (stools, vaginal secretions), at birth (meconium, colostrum) and at 10D PP (maternal stools, breastmilk, neonate stools). Detection of the probiotic strains was performed using single nucleotide variants method to confirm engraftment.

Results: 52 women were recruited and 45 of them were analysed. There were no statistical differences between groups’ characteristics at baseline. All mothers (100%) were breastfeeding from delivery to 10D PP. Probiotic strains in mother's stools were detected in 91% of cases at 37 WG (group A) and 87% of cases at 10D PP (group B)). Strains were only marginally detected in the vaginal samples. No probiotic strains were detected in meconium or colostrum (group A). Only one strain was found in 2 samples of breastmilk at 10D PP (group B). In the babies’ stools at 10D PP, probiotics were detected in 17% (group A) and 61% (group B) respectively. The B. Infantis strain HA116 was the most detected strain in babies’ stools. No severe adverse events were reported during the study.

Conclusion: Vertical transmission was evidenced by the presence of probiotic strains in babies' stools to a greater extent in the neonatal period than in the ante-natal period. However, probiotic strains were not detected in meconium or breastmilk.