I take your point but it’s not binary - in the sense that I have strong doubts that the MIC (Minimum inhibitory concentration) of antibiotics would touch much o

I take your point but it’s not binary - in the sense that I have strong doubts that the MIC (Minimum inhibitory concentration) of antibiotics would touch much of a colonisation in a neonate should it be present. Having a single dose of abx in an adult doesn’t kill everything; the intent of a pre-surgical dose of abx is because evidence shows it significantly reduces post op infections; and the antibiotic used is active primarily against gram positives (cephazolin 1-2g) whereas Pelomonas puraquae is a gram negative anerobic rod and more than likely not going to be touched, even if the MIC is reached (and my experience of obstetric theatres is the antibiotic usually (80% of the time) goes in only minutes before skin incision. So; a couple of things: - presuming no contamination in the study, the primary coloniser of neonates appears to be a gm -ve rod - antibiotics given for caesars are active against gm +ves /aerobes So while there may be a mechanism, it’s not highly plausible in light of the other known mechanisms affecting Caesar births vs natural (ie bacterial microbiome pickup during traversal of the birth canal) about which there is significant evidence regarding immune priming