Women who begin pregnancy with two or more pre-existing, long-term physical or mental health conditions face a significantly higher risk of various complications, according to new research published in The Lancet Public Health. The study analyzed over 2.2 million pregnancies and birth events recorded between 2000 and 2022 across England, Scotland, Wales, and Northern Ireland.
New Study Links Pre-Existing Health Conditions to Higher Pregnancy Complication Risks
Led by researchers at King’s College London, Queen’s University Belfast, Bristol NHS Foundation Trust, the University of Birmingham, Swansea University, and the University of St Andrews, the observational study is the largest of its kind. The findings indicate that around one in five pregnant women in the UK live with multiple long-term conditions.
Specific Pregnancy Risks Identified
The research revealed that women with multiple long-term conditions experience elevated risks during pregnancy compared to those with no pre-existing conditions:
- A 20% higher risk of miscarriage
- A 69% higher risk of severe nausea and vomiting
- Around four times the risk of antenatal anxiety and depression
- More than double the risk of venous thromboembolism, which involves blood clots forming inside veins such as in deep vein thrombosis and pulmonary embolism
- A 42% higher risk of pre-eclampsia, a complication causing high blood pressure
- A 32% higher risk of placental abruption, where the placenta separates from the womb before birth
- A 26% higher risk of gestational diabetes
Furthermore, the data showed that risks increased with each additional condition. For women with three or more pre-existing conditions, the risk of venous thromboembolism rose to more than three-and-a-half times that of women with no long-term health conditions.
Clinical Challenges and Call for Restructured Maternity Services
Professor Krishnarajah Nirantharakumar, a Clinical Professor of Public Health and Health Data Science at King’s College London, principal investigator, and joint senior author, noted that the findings support recognizing multiple long-term conditions as a distinct marker of antenatal risk.
According to Nursinginpractice, Dr. Kelly-Ann Eastwood, joint senior author, honorary lecturer at Queen’s University Belfast, and consultant obstetrician at St Michael’s Hospital within the Bristol NHS Foundation Trust, stated that the results help define the urgent clinical challenges for both patients and clinicians across the UK. She added that the findings highlight a pressing need to restructure existing maternity services.
Researchers emphasized that current care pathways are largely centered on individual conditions and may fail to adequately meet the needs of women managing multiple diagnoses. Experts recommended identifying these patients at maternity booking, assessing both physical and mental health needs simultaneously, and coordinating obstetric, primary care, and mental health services around them.
Study Limitations
The study authors noted limitations to their work. Because the research was observational and relied on routinely collected records, some conditions and outcomes may have been under-recorded, and residual confounding could not be entirely excluded. Future work by the MuM-PreDiCT consortium will examine birth and child outcomes while identifying which specific combinations of conditions carry the greatest risk.
