 Comprehensive Microbiome Survey of Preterm Infants: Biological and environmental samples will be collected from enrolled mother and infant subjects Study Group 1 from the time of delivery through the first two weeks of life. For stool samples, a minimum of 1 gram will be collected. For blood samples, 4 ml will be collected. Infant stool samples will be collected from diapers. Maternal stool and vaginal samples will be collected at the time of caesarian section using a sterile nylon swab of the distal rectum and vagina. Skin samples will be collected by gentling rubbing the target area with a sterile nylon swab moistened with sterile saline. Breast milk samples will be scavenged from left over material after the feeding of each infant. Since breast milk undergoes a single thaw from frozen storage per feeding, excess milk may not be stored for subsequent feedings and would be put to waste. A portion of stool, blood, and breast milk samples will be placed into sterile, nucleic acid-free tubes. An additional portion of stool, blood, and breast milk samples will be placed into sterile, nucleic acid-free tubes containing the preservative RNA later. All stool, breast milk, and blood samples will be frozen at -20C within 1 hour of collection. Remaining samples will be placed at 4C within 18 hr of collection. Samples will be transferred to -80C storage within 24 hours of collection. A label carrying a unique sample number will be placed on each sample as it is collected. A binder with sample labels and a log of sample numbers, time of collection, sample type key, and special notes regarding collection, will be placed at the bedside. 