Adult EEG Reactivity in Rat Offspring After an Uncomplicated Birth Is Not Significantly Altered by Gestational Antibiotics

Prolonged gestational antibiotic exposure was previously reported to impair EEG reactivity in adult offspring after perinatal asphyxia. It remained unclear to what extent the effect depended on perinatal insult. We assessed adult EEG reactivity after uncomplicated birth using the same gestational treatment paradigm. Pregnant Wistar rats received antibiotics (AB), probiotics (P), combined treatment (AB&P), or control (C). Adult offspring (AB: 5; P: 8; AB&P: 7; C: 9; 14 males) underwent intermittent photic stimulation during chloral-hydrate-induced EEG burst suppression. Reactivity to 60 s stimulation was quantified in 180 s trials using burst count reactivity (BCR) and the burst-suppression reactivity index (BSRi). After baseline burst count filtering, 200 trials were retained across groups. BCR did not differ significantly between groups. No multiplicity-corrected pairwise comparison identified a specific treatment-associated difference in BCR or BSRi. Mixed-effects models accounting for repeated trials likewise showed no significant overall group effect. Our small cohort did not provide evidence for a long-term effect of gestational antibiotic or probiotic exposure following uncomplicated birth. Together with the previous report, we suggest that gestational antibiotic administration could impair resilience to perinatal asphyxia at an exposure level without a readily detectable effect after uncomplicated birth.