The placental microbiome: yea, nay or maybe?

Abstract

Challenging dogma is a frightful thing. Since Aagard, et al (Sci Transl Med 2014;6:237ra65) reported that normal placenta harbors a microbiome that resembles the microbiome of the oral cavity, challenging the prevailing dogma of the sterile uterine environment, investigative teams have published conflicting results either refuting or confirming their findings. Recently, Kuperman, et al, (BJOG 2019;Aug 2:https://doi.org/10.1111/1471-0528,15896) reported analyses of 28 human placentas and 6 murine placentas and found no evidence of a placental microbiome. These data support other compelling recent studies calling into question the existence of a placental microbiome (de Goffau, et al, Nature 2019;572: 329-334 and Theis, et al, AJOG 2019;267e1-267e39).