Neonatal serologic response at term to the genital mycoplasmas

Genital mycoplasmas are frequently found in the amniotic fluid (AF) of women with ruptured membranes but are infrequent pathogens in the neonates born to these women. The serologic response to the genital mycoplasmas, Mycoplasma hominis and Ureaplasma urealyticum, was studied in 35 mother-baby pairs following term deliveries. Amniotic fluid and neonatal surface cultures were obtained in all cases, as were maternal and neonatal acute and convalescent sera. Despite significant maternal serologic response, there was essentially no neonatal response. Mothers with M. hominis in the AF were significantly more likely than those with negative cultures for M. hominis to exhibit IgG seroconversion and had significantly greater changes in IgG concentrations. Their infants, however, did not exhibit a significant seroresponse regardless of the AF and neonatal culture results. There was also a significant maternal seroresponse to U. urealyticum. However, this did not correlate with the presence of U. urealyticum in the AF. Significantly fewer neonates exhibited a seroresponse to U. urealyticum, again with no relation to culture results.