"The first germs to colonize a newborn delivered vaginally come almost exclusively from its mother. But the first to reach an infant born by cesarean section come mostly from the environment  particularly bacteria from inaccessible or lessscrubbed areas like lamps and walls and skin cells from everyone else in the delivery room. Photo  The transfer of the maternal microbiome occurs naturally after a a vaginal birth. After a b Csection researchers transferred the neonatal microbiome from the mothers with a c gauze treatment.Credit Kim CaesarNature Publishing Group That difference some experts believe could influence a childs lifelong health. Now in the first study of its kind researchers on Monday confirmed that a mothers beneficial microbes can be transferred at least partially from her vagina to her baby after a Csection. The small proofofprinciple study suggests a new way to inoculate babies said Dr. Maria Gloria DominguezBello an associate professor of medicine at New York University and lead author of the report published on Monday in Nature Medicine. The study is extremely important said Dr. Jack Gilbert a microbial ecologist at Argonne National Laboratory who did not take part in the work. Just understanding that its possible is exciting. But it will take further studies following Csection babies for many years to know to what degree if any the method protects them from immune and metabolic problems he said. Some epidemiological studies have suggested that Csection babies may have an elevated risk for developing immune and metabolic disorders including Type  diabetes httpsdiabetes.diabetesjournals.orgcontent.extract allergies asthma and obesity. Scientists have theorized that these children may be missing key bacteria known to play a large role in shaping the immune system from the moment of birth onward. To replace these microbes some parents have turned to a novel procedure called vaginal microbial transfer. A mothers vaginal fluids  loaded with one such essential bacterium lactobacillus that helps digest human milk  are collected before surgery and swabbed all over the infant a minute or two after birth. An infants first exposure to microbes may educate the early immune system to recognize friend from foe Dr. DominguezBello said. Friendly bacteria like lactobacilli are tolerated as being like oneself. Those from hospital ventilation vents or the like may be perceived as enemies and be attacked. These early microbial interactions may help set up an immune system that recognizes self from nonself for the rest of a persons life Dr. DominguezBello said. In the United States about one in three babies are delivered by Csection a rate that has risen dramatically in recent decades. Some hospitals perform the surgery on nearly seven in ten women delivering babies. An ideal Csection rate for lowrisk births should be no more than  percent according to the World Health Organization. Dr. DominguezBellos study involved  babies born at the University of Puerto Rico hospital in San Juan where she recently worked. Seven were born vaginally and  by elective Csection. Of the latter four were swabbed with the mothers vaginal microbes and seven were not. Microbes were collected on a folded sterile piece of gauze that was dipped in a saline solution and inserted into each mothers vagina for one hour before surgery. As the operations began the gauze was pulled out and placed in a sterile collector. One to two minutes after the babies were delivered and put under a neonatal lamp researchers swabbed each infants lips face chest arms legs back genitals and anal region with the damp gauze. The procedure took  seconds. Dr. DominguezBello and her colleagues then tracked the composition of microbes by taking more than  oral skin and anal samples from the newborns as well as vaginal samples from the mothers over the first month after birth. For the first few days ambient skin bacteria from the delivery room predominated in the mouths and on the skin of Csection babies who were not swabbed Dr. DominguezBello said. But in terms of their bacterial colonies the infants swabbed with the microbes closely resembled vaginally delivered babies she found especially in the first week of life. They were all covered with lactobacilli. Gut bacteria in both Csection groups however were less abundant than that found in the vaginally delivered babies. Anal samples from the swabbed group oddly contained the highest abundance of bacteria usually found in the mouth. The results show the complexity of labor said Dr. Alexander Khoruts a microbial expert and associate professor of medicine at the University of Minnesota. It cannot be simplified to a neat effortless passage of the infant through the birth canal he said. As the month progressed the oral and skin microbes of all infants began to resemble normal adult patterns Dr. DominguezBello said. But fecal bacteria did not probably because of breast or formula feeding and the absence of solid foods. The transfer fell short of full vaginal birthlike colonization for two reasons Dr. DominguezBello said. Compared to infants who spent time squeezed inside the birth canal those who were swabbed got less exposure to their mothers microbes. And all infants delivered by Csection were exposed to antibiotics which also may have reduced the number and variety of bacteria colonizing them. A larger study of vaginal microbial transfer is underway at N.Y.U. Dr. DominguezBello said. Eightyfour mothers have participated so far. Infants delivered both by Csection and vaginally will be followed for one year to look for differences in the treated and untreated groups and to look for complications. Thus far the swabbing has proved entirely safe. The procedure is not yet recommended by professional medical societies said Dr. Sara Brubaker a specialist in maternal and fetal medicine at N.Y.U. Until more is known physicians are hesitant to participate. But it has hit the lay press she said. Patients come in and ask for it. They are doing it themselves. Dr. Brubaker is one of them. When her daughter was born three and a half months ago she arranged to have her baby swabbed."