This important work was led by researchers and clinicians from the University of Birmingham, King’s College London, Queen’s University Belfast and Bristol NHS Foundation Trust as part of the MuM-PreDiCT consortium. The team analysed 2,225,701 pregnancies and birth events recorded between 2000 and 2022 in five datasets spanning England, Scotland, Wales and Northern Ireland.
Around one in five pregnant women in the UK lives with multiple long-term conditions, yet their combined effect on pregnancy has been poorly understood. The MuM-PreDiCT research group set out to change this.
They found that, compared with women with no long-term conditions, women with multiple long-term conditions had:
- more than double the risk of venous thromboembolism
- 42% higher risk of pre-eclampsia
- 69% higher risk of hyperemesis
- 32% higher risk of placental abruption
- 26% higher risk of gestational diabetes
- 20% higher risk of miscarriage
- around four times higher risks of antenatal anxiety and depression
Risks rose with each additional condition. Among women with three or more conditions, the risk of venous thromboembolism was more than three-and-a-half times that of women with none.
These findings have important implications for how maternity services are designed and delivered.
Dr Kelly-Ann Eastwood, Consultant Obstetrician at Bristol NHS Foundation Trust and Honorary Lecturer at Queen’s University Belfast and University of Bristol, is joint senior author of the paper. She said:
Our results help define the urgent clinical challenges facing both women entering pregnancy with multiple long-term conditions, and clinicians caring for them across the UK.
“Supporting recommendations from recent national maternity and neonatal investigation reports, there is a critical need to address healthcare inequalities, and improve support for women with pre-existing mental health conditions.
“These findings highlight the pressing need to restructure existing maternity services to improve antenatal outcomes.”
Dr Steven Wambua of King’s College London, joint first author, said:
“Maternity care is still largely organised around single conditions, but one in five women now enters pregnancy with two or more.
“By harmonising five datasets covering all four UK nations, we could show consistently and across a much broader range of outcomes than before, that these women face higher risks and that risk climbs with every additional condition.”
Professor Krishnarajah Nirantharakumar of King’s College London, MuM-PreDiCT principal investigator and joint senior author, said:
“These findings make a strong case for recognising multiple long-term conditions as a marker of antenatal risk in its own right. That means identifying these women at maternity booking, assessing physical and mental health needs together, and joining up obstetric, primary care and mental health services around them.
“The near four-fold risk of antenatal anxiety and depression is particularly striking, and points to perinatal mental health support as an urgent priority.”
The authors note that, as an observational study using routinely collected records, some conditions and outcomes may be under-recorded. They also couldn’t rule out the influence of other unstudied risk factors on their overall findings.
Next, the team will look at birth and child outcomes, identifying which combinations of conditions carry greatest risk to mothers and their babies.
Read the paper
Antenatal outcomes for women with multiple long-term conditions in pregnancy: a UK-wide retrospective cohort study
Kent L, Wambua S, Singh M, et al, on behalf of the MuM-PreDiCT Group. The Lancet Public Health 2026.