Outcomes for women admitted for labour care to alongside midwifery units in the UK following a postpartum haemorrhage in a previous pregnancy: A national population-based cohort and nested case-control study using the UK Midwifery Study System (UKMidSS)

Alessandra Morelli; Jane Rogers; Julia Sanders; Jennifer J Kurinczuk; Rachel Rowe

doi:10.1016/j.wombi.2022.11.002

Outcomes for women admitted for labour care to alongside midwifery units in the UK following a postpartum haemorrhage in a previous pregnancy: A national population-based cohort and nested case-control study using the UK Midwifery Study System (UKMidSS)

Women Birth. 2023 May;36(3):e361-e368. doi: 10.1016/j.wombi.2022.11.002. Epub 2022 Nov 12.

Authors

Alessandra Morelli¹, Jane Rogers², Julia Sanders³, Jennifer J Kurinczuk⁴, Rachel Rowe⁵

Affiliations

¹ NIHR Policy Research Unit in Maternal and Neonatal Health and Care, National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Old Road Campus, Oxford OX3 7LF, United Kingdom. Electronic address: alessandra.morelli@npeu.ox.ac.uk.
² University Hospitals Southampton, Coxford Road, Southampton SO16 5YA, United Kingdom.
³ School of Healthcare Sciences, College of Biomedical and Life Sciences, Cardiff University Room 1.7, Ty Dewi Sant, Heath Park, Cardiff CF14 4XN, United Kingdom.
⁴ NIHR Policy Research Unit in Maternal and Neonatal Health and Care, National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Old Road Campus, Oxford OX3 7LF, United Kingdom.
⁵ NIHR Policy Research Unit in Maternal and Neonatal Health and Care, National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Old Road Campus, Oxford OX3 7LF, United Kingdom. Electronic address: https://twitter.com/@RachelRowe3.

PMID: 36376224
DOI: 10.1016/j.wombi.2022.11.002

Abstract

Background: Women who have experienced a postpartum haemorrhage (PPH) 'requiring treatment or transfusion' are typically advised to plan birth in obstetric-led settings in subsequent pregnancies. Many UK alongside midwifery units (AMU) admit women for labour care following a previous PPH. We aimed to describe outcomes in women admitted for labour care to AMUs following a previous PPH, compare outcomes with other multiparous women admitted to the same AMUs, and explore risk factors for recurrence.

Methods: A national cohort and nested case-control study using the UK Midwifery Study System (UKMidSS), between August 2018 and April 2019. Multivariable Poisson regression and logistic regression were performed to compare outcomes and investigate risk factors for recurrence.

Findings: Women who experienced a previous PPH were significantly more likely than comparison women to: have a PPH requiring transfer to obstetric care (4·2% vs. 2·4%, aRR=1·65, 95% CI 1·14-2·38), be transferred to obstetric care for any reason (17·8% vs 11·9%; aRR=1·41; 95% CI 1·09-1·83), and have any PPH≥ 500 ml (22·7% vs 11·1%, aRR=1·86, 95% CI 1·49-2·32). Among women with a previous PPH, previous blood loss > 1500 ml; uterotonics for previous PPH; Caesarean associated with previous PPH; gestation at admission and higher birthweight were independent risk factors for PPH.

Conclusion: Women considering birth in an AMU after a previous PPH should be advised that they are at increased risk of experiencing a subsequent PPH requiring transfer to obstetric care, compared with other multiparous women who have not had a PPH. The absolute risk of a subsequent PPH in this group is low and comparable to the overall risk of having a PPH among women having a spontaneous vaginal birth in England.

Keywords: Birthing centers; Labor; Midwifery-led care; Postpartum haemorrhage; Risk factors.

MeSH terms

Case-Control Studies
England
Female
Humans
Labor, Obstetric*
Midwifery*
Postpartum Hemorrhage* / epidemiology
Postpartum Hemorrhage* / etiology
Pregnancy