Impact of intrapartum antibiotics on the developing microbiota: a review

Abstract

The perinatal period sets the basis for the later physiological and immune homeostasis of the individual, with the intestinal microbiota being an important contributor to driving this homeostasis development. Therefore, the initial establishment and later development of the microbiota during early life may play a key role in later health. This early establishment of the intestinal microbiota is known to be affected by several factors, with gestational age, delivery mode, and feeding habits being extensively studied ones. Other factors are not so well understood, although knowledge has been accumulating in the last years. Among them, a factor of great relevance is the effect of perinatal exposure to antibiotics. Administration of intrapartum antimicrobial prophylaxis (IAP) to women during the delivery process represents the most common form of exposure to antibiotics during the perinatal period, present in around 30% of deliveries. During the last decade, evidence has accumulated demonstrating that IAP alters intestinal microbiota development in neonates. Moreover, recent evidence indicates that this practice may also be altering the infant intestinal resistome by increasing the levels of some antibiotic resistance genes. This evidence, as reviewed in this manuscript, suggests the interest in promoting the rational use of IAP. This practice has significantly reduced the risk of neonatal infections, but now the accumulating knowledge suggests the need for strategies to minimize its impact on the neonatal microbiota establishment.

Maternal-infant antibiotic resistance genes transference: what do we know?

“…Two seminal studies demonstrated the impact of IAP on the prevalence of ARGs and mobile elements in vaginally-delivered full-term babies, showing also a beneficial effect of breastfeeding on the ARGs burden 15 , 129 . Most of the current studies concluded that the selective pressure exerted by IAP favors the presence of different bacteria carrying ARGs, most of them species belonging to Pseudomonadota phyla or Staphylococcus genus 128 . In addition, IAP has also been associated with increments of ARGs in other body microbiomes, such as the nasopharynx and oral microbiota 128 .…”

“…Most of the current studies concluded that the selective pressure exerted by IAP favors the presence of different bacteria carrying ARGs, most of them species belonging to Pseudomonadota phyla or Staphylococcus genus 128 . In addition, IAP has also been associated with increments of ARGs in other body microbiomes, such as the nasopharynx and oral microbiota 128 .…”

“…The effect of this treatment on the gut microbiome has gained attention the last decade and several articles have demonstrated an impact of IAP on the gut microbiota development. Several common findings highlighted the increment of Enterobacteriaceae and the reduction of strict anaerobes such as Bifidobacterium and Bacteroides genus 128 . In addition, it has been observed a negative influence of IAP on the correct development of bifidobacterial community in newborns during the first months of life.…”

Impact of intrapartum antibiotic prophylaxis on the oral and fecal bacteriomes of children in the first week of life: a preliminary study

“…Their results showed that colonization by Bi dobacteria was detected in fewer No-IAP neonates than in IAP neonates. The topic was followed by more than 20 culture-independent bacteriological studies investigating IAP and gut microbiota development since 2015 (72). Only some of the studies evaluated the effect of IAP in the rst days after birth in full-term neonates (12,21,27,30,31,70,71,(73)(74)(75) 21) observed a decrease in Bi dobacterium and Bacteroides spp.…”

Old Folks, Bad Boon: Antimicrobial Resistance in the Infant Gut Microbiome

“…This practice also leads to a substantial increase in Enterobacteriaceae in the neonatal gut microbiota during the first weeks of life. The changes caused by IAP at the taxonomic level are comparable to those triggered by the direct administration of antibiotics to infants [ 115 ]. IAP has also been reported to cause changes in the load of ARGs in the gut microbiota of newborns.…”