Abruptio placentae.

Analysis of blood samples from pregnant women has shown that the mean histamine level starts to rise when the plasma ascorbic acid level falls below 1.0 mg/100 ml; it is doubled when the ascorbate level falls to 0.5 mg/100 ml and quadrupled when it falls below 0.2 mg/100 ml. The incidence of abruptio placentae was found to be seven out of 355 (or 2.0%) in women who had plasma ascorbic acid levels above 0.4 mg/100 ml and six out of 31 (19.4%) in women with plasma ascorbate levels below 0.4 mg/100 ml. This difference is highly significant. It is suggested that ascorbic acid deficiency and histamine excess play leading roles in the etiology of abruptio placentae.