Restoration of the Gut Microbiome After Cesarean Section

This study aims to develop a therapy for restoring the gut microbiome in infants born via CS. The Study will conduct a randomized, placebo-controlled feasibility trial to assess the ability of microbiome restoration by FMT and FVT in infants born by cesarean section.

Inclusion Criteria: * Gestational age \< week 38+0 days * Proficient in spoken/written Danish * Single pregnancy (no twins or triplets) * Pre-pregnancy BMI between 18.5 and 35 kg/m2 * No chronic intestinal, endocrine, cardiac, or kidney disorders * No known gestational complications (gestational diabetes, preeclampsia, gestational hypothyroidism) * No regular use of prescription medication or any drugs that, in the research team's opinion, may interfere with the study's results. * Willingness to abstain from giving the child products with probiotics (fermented dairy like yogurt or A38 are allowed). Exclusion Criteria: Maternal: * Use of antibiotics within one month of stool donation * Acute gastroenteritis within one month of stool donation * Use of antibiotics within one month of birth * Time since last travel abroad relative to data of fecal donation according to the requirements for blood donations ("Regler for tappepauser" - blooddonor.dk) * Positive test results for pathogens during donor material screening. * Antibiotic treatment at birth (vaginal births only) * Spontaneous onset of labor or emergency cesarean section before scheduled cesarean section. Infant: * Instances of major birth defects or intrauterine growth retardation (IUGR) * Infants requiring pediatric support at the time of transplant administration