Clinical microbiology The impact of perinatal probiotic intervention on gut microbiota: Double-blind placebo-controlled trials in Finland and Germany qukasz Grze  skowiak a, * , Minna-Maija Grönlund b , Christina Beckmann c , Seppo Salminen a , Andrea von Berg c , Erika Isolauri b a Functional Foods Forum, University of Turku, Itainen Pitkakatu 4 A 5, 20014 Turku, Finland b Department of Pediatrics, Turku University Hospital and University of Turku, Turku, Finland c Department of Pediatrics, Marien-Hospital-Wesel, Wesel, Germany article info Article history: Received 30 June 2011 Received in revised form 16 September 2011 Accepted 21 September 2011 Available online 29 September 2011 Keywords: Infant Gut microbiota Probiotic Breastfeeding Formula-feeding abstract Specific probiotic combinations during early feeding, via the mother or incorporated in early formula- feeding, mold the intestinal microbiota composition in infants. The objective was to analyze the impact of probiotic administration to mother or infant on gut microbiota composition in 6-month-old Finnish and German infants. In Finland probiotics were given to mothers (n ¼ 79) for 2 months prior to and 2 months after delivery. In Germany probiotics were started in infants (n ¼ 81) at weaning, at the latest at 1 month of age, and continued for 4 months. A breast-fed group of 6-month-old infants (22 from Finland, 8 from Germany) were compared. Gut microbiota were analyzed by FCM-FISH and qPCR methods. In breast-fed infants a trend toward higher counts of bifidobacteria was detected in Finland (p ¼ 0.097) as against Germany, where a more diverse microbiota was reflected in higher Akkermansia (p ¼ 0.003), Clostridium histolyticum (p ¼ 0.035) and BacteroidesePrevotella (p ¼ 0.027) levels and a higher percentage of Akkermansia (p ¼ 0.004). Finnish LPR þ BL999 intervention group (Lactobacillus rhamnosus LPR and Bifidobacterium longum BL999) had higher percentages of fecal LactobacilluseEnter- ococcus (9.0% vs. 6.1% placebo, p ¼ 0.003) and lower bifidobacteria levels (10.03 log cells/g vs. 10.68 log cells/g placebo, p ¼ 0.018). Probiotic treatment had different impacts on gut microbiota composition in Finnish and German infants due to differences in mode of feeding and the early commensal microbiota. Probiotic treatment had different impacts on gut microbiota composition in Finnish and German infants due to differences in mode of feeding and the basic commensal microbiota. Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction Intestinal colonization of a newborn starts at birth and continues during infancy. After weaning, the gut microbiota becomes more diverse, and continues to develop toward an adult microbiota [1]. Microbiota development depends on the first inoculum, the mother’s microbiota, mode of delivery and the environment, including feeding practices and use of antimicrobials [2,3]. Bifidobacteria constitute up to 60e70% of the total microbiota of healthy breast-fed infants [2,4,5], with Bifidobacterium longum, Bifidobacterium infantis and Bifidobacterium breve as the most predominant species in different geographic areas [6e10]. The gut microbiota of formula-fed infants, again, may be more diverse, harboring more Bacteroides, Clostridium and Enterobacteriaceae [3,6]. Deviations in microbiota composition such as low numbers or aberrant species of bifidobacteria have been associated with a higher risk of allergic and infectious diseases [11,12] and even obesity [13,14]. A probiotic is defined as a “live microorganism which when administered in adequate amounts confers a health benefit on the host” [15]. Administration of probiotics perinatally and during the first months of life may have a long-term beneficial influence on the composition and development of the infant’s bifidobacteria, potentially leading to a reduced risk of atopic disease [16,14]. The limited number of intervention studies thus far have yielded different outcomes [17,18]. Reasons for this may be related to differences in target populations or probiotic strains used in preparation and in dosing together with the mode of administra- tion. We hypothesized here that the diet of the infant, the probiotic preparation, but also the pre-existing microbiota and the environ- ment, may influence the probiotic potential to modify the gut microbiota composition. * Corresponding author. Tel.: þ358 23336818; fax: þ358 23336862. E-mail address: lukgrz@utu.fi (q. Grze skowiak). Contents lists available at SciVerse ScienceDirect Anaerobe journal homepage: www.elsevier.com/locate/anaerobe 1075-9964/$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.anaerobe.2011.09.006 Anaerobe 18 (2012) 7e13