Juliana Morais1,2, Cláudia Marques1,2, Diana Teixeira1,2,3, Catarina Durão1,4, Ana Faria1,2,5, Sara Brito6, Manuela Cardoso7, Israel Macedo6, Teresa Tomé6, Conceição Calhau8,9,10. 1. Nutrition and Metabolism, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisbon, Portugal. 2. CINTESIS, Center for Health Technology Services Research, Porto, Portugal. 3. Unidade Universitária Lifestyle Medicine José de Mello Saúde by NOVA Medical School, Lisbon, Portugal. 4. EPIUnit - Institute of Public Health, Universidade do Porto, Porto, Portugal. 5. Comprehensive Health Research Centre, Universidade NOVA de Lisboa, Lisbon, Portugal. 6. Neonatal Intensive Care Unit, Maternidade Dr. Alfredo da Costa, Centro Hospitar de Lisboa Central, Lisbon, Portugal. 7. Nutrition and Dietetics Unit, Maternidade Dr. Alfredo da Costa, Centro Hospitalar de Lisboa Central, Lisbon, Portugal. 8. Nutrition and Metabolism, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisbon, Portugal, ccalhau@nms.unl.pt. 9. CINTESIS, Center for Health Technology Services Research, Porto, Portugal, ccalhau@nms.unl.pt. 10. Unidade Universitária Lifestyle Medicine José de Mello Saúde by NOVA Medical School, Lisbon, Portugal, ccalhau@nms.unl.pt.
Abstract
BACKGROUND: Preterm infants are especially vulnerable to gut microbiota disruption and dysbiosis since their early gut microbiota is less abundant and diverse. Several factors may influence infants' gut microbiota, such as the mother's diet, mode of delivery, antibiotic exposure, and type of feeding. OBJECTIVES: This study aims to examine the factors associated with very-preterm neonate's intestinal microbiota, namely: (1) type of infant-feeding (breast milk, donor human milk with or without bovine protein-based fortifier, and preterm formula); (2) maternal diet; and (3) mode of delivery. METHODS: This is an observational study conducted in a cohort of very preterm infants hospitalized in the neonatal intensive care unit of Maternidade Dr. Alfredo da Costa. After delivery, the mothers are asked to collect their own fecal samples and are invited to complete a semiquantitative food frequency questionnaire. The maternal diet will be classified in accordance to the Mediterranean Diet adherence score. Stool samples have been collected from very premature infants every 7 days for 21 days. DNA has been extracted from the fecal samples, and different bacterial genus and species will be quantified by real-time polymerase chain reaction. RESULTS AND CONCLUSIONS: It is hypothesized that significant differences in the microbiota composition and clinical outcomes of very preterm infants will be observed depending on the type of infant feeding. In addition, this study will clarify how pasteurized donor's milk influences the intestinal microbiota colonization of preterm infants. This is a pioneer study developed in collaboration with the country's Human Milk Bank. We also expect to find microbiota alterations in infants according to the mode of delivery and to maternal diet. This study will contribute to increase the evidence on the effects of breast or donor human milk and its fortification with a bovine protein-based fortifier on infant microbiota.
BACKGROUND: Preterm infants are especially vulnerable to gut microbiota disruption and dysbiosis since their early gut microbiota is less abundant and diverse. Several factors may influence infants' gut microbiota, such as the mother's diet, mode of delivery, antibiotic exposure, and type of feeding. OBJECTIVES: This study aims to examine the factors associated with very-preterm neonate's intestinal microbiota, namely: (1) type of infant-feeding (breast milk, donorhuman milk with or without bovine protein-based fortifier, and preterm formula); (2) maternal diet; and (3) mode of delivery. METHODS: This is an observational study conducted in a cohort of very preterm infants hospitalized in the neonatal intensive care unit of Maternidade Dr. Alfredo da Costa. After delivery, the mothers are asked to collect their own fecal samples and are invited to complete a semiquantitative food frequency questionnaire. The maternal diet will be classified in accordance to the Mediterranean Diet adherence score. Stool samples have been collected from very premature infants every 7 days for 21 days. DNA has been extracted from the fecal samples, and different bacterial genus and species will be quantified by real-time polymerase chain reaction. RESULTS AND CONCLUSIONS: It is hypothesized that significant differences in the microbiota composition and clinical outcomes of very preterm infants will be observed depending on the type of infant feeding. In addition, this study will clarify how pasteurized donor's milk influences the intestinal microbiota colonization of preterm infants. This is a pioneer study developed in collaboration with the country's Human Milk Bank. We also expect to find microbiota alterations in infants according to the mode of delivery and to maternal diet. This study will contribute to increase the evidence on the effects of breast or donorhuman milk and its fortification with a bovine protein-based fortifier on infant microbiota.