Raised nitric oxide levels may cause atonic postpartum hemorrhage in women with anemia during pregnancy.

Objective: To determine the association of hemoglobin (Hb) and plasma nitrite (PN) concentrations on admission to the delivery ward with the occurrence of atonic postpartum hemorrhage (PPH).

Methods: Of 319 women admitted to the Department of Obstetrics and Gynecology, Dayrout General Hospital, Assiut, Egypt, for delivery in July 2010, 200, who were not considered to be at risk of atonic PPH, were eligible for inclusion. Plasma levels of Hb and nitrite were measured on admission.