Intravenous inoculation of pregnant BALB/c mice with 10(3) to 10(5) Absidia corymbifera spores resulted in mycotic placentitis when 10(4) or more spores were given. Compared with challenge on day 10, challenge on days 12 and 14 of pregnancy resulted in significantly more placentas being infected. Placentitis was seen in 2.4 to 6.7% of the placentas from animals given 10(4) spores on days 12 and 14 respectively, compared with 14.0 and 15.2% of the placentas in animals challenged on the same days with 10(5) spores. Absidia corymbifera did not have particular affinity for placental localization because extrauterine organs were also frequently [abstract incompletely published]