Risk factors for hospital admission related to excessive and/or prolonged postpartum vaginal blood loss after the first 24 h following childbirth

Abstract

A population case-control study was used to determine risk factors for excessive and/or prolonged vaginal bleeding (described collectively as vaginal loss problems) and uterine infection from 24 h to 3 months postpartum. Data were obtained from women whose maternity care took place in one of two health districts in the south of England. The cases were women remaining in or admitted to hospital with excessive or prolonged vaginal blood loss from 24 h to 3 months postpartum. Two controls for each case were identified; these were women whose delivery was the nearest in time and in the same location as the case delivery. Medical and midwifery records were searched retrospectively to cover hospital admissions for vaginal blood loss problems or uterine infection in postpartum women from 1 January 1994 to 31 December 1995. Data were analysed for 243 cases and 486 controls. Univariable analysis identified 28 variables associated with being a case. Using multivariable analysis, nine factors remained in the final model, with a history of secondary postpartum haemorrhage (PPH) being the most strongly predictive (OR [95% confidence interval] 6.0 [2.1, 16.8]). Vaginal bleeding prior to 24 weeks' gestation (OR 3.0 [1.6, 5.9]), third trimester hospital admission (OR 2.0 [1.4, 2.8]), maternal smoking (OR 2.7 [1.8, 3.9]), a prolonged (OR 3.1 [1.2, 7.5]) or incomplete third stage (OR 2.1 [1.0, 4.4]), and primary PPH (OR 4.7 [1.9, 11.6]) for blood loss >500 mL, were predictive of becoming a case. No significant association was identified for parity (OR 1.1 [0.8, 1.5]) or method of delivery, spontaneous (OR 1.0 [0.7, 1.3]), instrumental (OR 1.4 [0.9, 2.2]) or operative (OR 1.2 [0.8, 1.9]). This is a neglected area of women's health after childbirth, and the value of this study is in the identification of potential risk factors for postpartum morbidity related to vaginal blood loss. Where morbidity occurs, early diagnosis, management and treatment are likely to reduce its extent or duration. It is considered that raising awareness about these factors, both among healthcare professionals and women themselves, may play an important part in the recognition and treatment of postpartum morbidity.