We conducted a systematic review of the literature to determine the amount and duration of blood loss 24 hours to 12 weeks after delivery.
We searched MEDLINE, CINAHL, and PubMed for studies between the years 1950 and 2011 that prospectively evaluated the amount and duration of blood loss from 24 hours to 12 weeks after delivery. Excluded were those that were only case studies, retrospective studies, studies not published in English, studies outside of the time frame, and studies that included only subjects from special populations.
From the 333 identified studies, 18 met inclusion criteria. There was variability in how the amount of blood loss was determined, ranging from subject self-assessment to objective measures, such as pad weight and spectrophotometric readings of hematin concentration. The reported duration of normal blood loss after delivery varied among the studies. Whereas the average duration of blood loss in these studies ranged from 24 to 36 days, in only 1 study was bleeding followed to cessation.
An understanding of bleeding patterns after delivery is important for clinicians to recognize deviations from normal, identify women at risk for delayed postpartum hemorrhage, and limit unnecessary interventions, yet studies reveal significant variability in amount and duration of normal lochial blood loss and methods of assessment that are inconsistent. This review draws attention to the need for the establishment of valid, reliable, and feasible methods to quantify normal and abnormal postpartum blood loss.