Molecular Structure and Content of Human Milk Oligosaccharides (HMOs) and Its Effect on Infant Health in China

Study Overview
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Brief Summary
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In the study, the composition and content of human milk oligosaccharides in premature delivery mothers in China will be examined to investigate the differences in oligosaccharide concentrations in preterm breast milk from different gestational weeks. This study will fill a gap in human milk research in China, provide theoretical basis for the superiority of breastfeeding, and provide more powerful nutritional support for the catch-up growth of preterm infants

Detailed Description
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Objective: Analyze and compare the differences in HMOs components among mothers who give birth at different gestational weeks; Longitudinal observation of weekly changes in HMOs concentrations of premature mothers within 1 month of delivery; Validate the association between HMOs components in preterm mothers and fecal intestinal flora in infants at 6 months of age. Research content The LC-MS method will be used to detect the content of HMOs in preterm mothers and compared with the corresponding components in term breast milk during the postpartum period to analyze the effects of different gestational weeks on HMOs; The intestinal flora 16S rDNA high-throughput sequencing method will be used to determine the bacterial gene profile in the fecal DNA samples of infants, and the differences between the gestational age groups (term and preterm infants) were compared, and the preterm infants in this group were plotted Evolution of intestinal flora within 6 months of birth; Use statistical methods to verify the association between HMOs components in preterm mothers and the establishment of intestinal flora in infants.

Official Title
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Study on the Molecular Structure and Content of Human Milk Oligosaccharides (HMOs) in Breast Milk and Its Effect on Infant Health in China

Conditions
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Child Development

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: (1) Be healthy, have no acute or chronic diseases, have no severe complications during pregnancy (2) Breastfeeding for more than 6 months and Volunteer to participate in this study (signed informed consent) (3) Age of maternal women: 20 35years (4) Breast milk is sufficient, and the amount of milk secreted each time is more than 30ml (5) No fatal, important organ system deformities and metabolic defects in neonates Exclusion Criteria: (1) for infants: Rescued to death or hospitalized due to critical illness during the study period (2)for lactating mothers: exposure to tobacco and alcohol during lactation, severe postpartum depression and other mental and psychological diseases, obesity (BMI> 28), use of antibiotics or antimetabolites, mastitis with fever within 7 days before specimen collection (T> 38.5 ℃),Suspension or termination of breastfeeding in the state of maternal and infant illness

Ages Eligible for Study
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Minimum Age: 7 Days
Maximum Age: 35 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Full term delivery<br>In the cooperative obstetric hospital, 30 cases of full-term delivery healthy mothers and their infants are selected. Each pair of nursing mothers and infants will complete the observation for 6 months. The samples of human milk and newborn feces are the experimental objects. | |
| Preterm delivery(35-37 weeks)<br>In the cooperative obstetric hospital, 30 cases of preterm delivery(35-37 weeks) mothers and their infants are selected. Each pair of nursing mothers and infants will complete the observation for 6 months. The samples of human milk and newborn feces are the experimental objects. | |
| Preterm delivery(32-35 weeks)<br>In the cooperative obstetric hospital, 30 cases of preterm delivery(32-35 weeks) mothers and their infants are selected. Each pair of nursing mothers and infants will complete the observation for 6 months. The samples of human milk and newborn feces are the experimental objects. | |
| Preterm delivery(28-32 weeks)<br>In the cooperative obstetric hospital, 30 cases of preterm delivery(28-32 weeks) mothers and their infants are selected. Each pair of nursing mothers and infants will complete the observation for 6 months. The samples of human milk and newborn feces are the experimental objects. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Human milk oligosaccharide detection | Liquid chromatography-mass spectrometer(LC-MS) will be used to quantitatively detect a total of 15 types of neutral oligosaccharides and acid oligosaccharides in different breast milk samples. Human milk samples will be collected four times for each mother after delivery (day7-12, day14-19, day21-26, day28-33). Only one series of samples will be collected for each mother, and 30 samples are needed for each group, totaling 480 human milk samples | Day7-12, Day14-19, Day21-26, Day28-33 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To dectect the intestinal flora with16s RNA high throughput sequencing | The results of bacterial gene profiles in fecal DNA samples of premature infants at different gestational ages will be analyzed as follows.First, bacterial genomic DNA in feces will be obtained using the QIAamp Fast DNA Stool Mini Kit(51604), and PCR amplification will be performed. After the Miseq library are successfully constructed, cluster preparation and sequencing will be performed with qualified libraries. The data obtained by the machine will be used for biological information analysis. By comparing OTU with database, species annotation will be performed on OTU.Based on OTU and species annotation results, species complexity analysis and inter-group species difference analysis will be carried out. Neonatal fecal samples will be collected four times for each infant after delivery at day7-12, day28-33, 3 months and 6 months of age. Only one series of samples will be collected from each infant, and 30 samples are needed for each group, totaling 480 fecal samples. | Day7-12, Day28-33, 3 months and 6 months | 
| Achieved the body weight of infants | Measured the body weight (grams) of infants at 8 time points: Day7-Day12, Day14-Day19, Day21-Day26, Day28-Day33, 2 months, 3 months, 4months and 6 months. | Day7-12, Day14-19, Day21-26, Day28-33, 2 months, 3 months, 4months and 6 months. | 
| Achieved the body length of infants | Measured the body length (mm) of infants at 8 time points: Day7-Day12, Day14-Day19, Day21-Day26, Day28-Day33, 2 months, 3 months, 4months and 6 months. | Day7-12, Day14-19, Day21-26, Day28-33, 2 months, 3 months, 4months and 6 months. | 
| Achieved the head circumference of infants | Measured the head circumference (mm) of infants at 8 time points: Day7-Day12, Day14-Day19, Day21-Day26, Day28-Day33, 2 months, 3 months, 4months and 6 months. | Day7-12, Day14-19, Day21-26, Day28-33, 2 months, 3 months, 4months and 6 months. | 
| Stool status of infants | Achieved the stool status( frequency, color, character)of neonatal based on health consultation at 8 time points: Day7-Day12, Day14-Day19, Day21-Day26, Day28-Day33, 2 months, 3 months, 4months and 6 months. | Day7-12, Day14-19, Day21-26, Day28-33, 2 months, 3 months, 4months and 6 months. | 
| Average daily formula intake | Achieved the average daily formula intake volume at 8 time points: Day7-Day12, Day14-Day19, Day21-Day26, Day28-Day33, 2 months, 3 months, 4months and 6 months. | Day7-12, Day14-19, Day21-26, Day28-33, 2 months, 3 months, 4months and 6 months. | 
| Disease and medication history | Record the disease and medication history of infants in each group | 6 months |