Maternal body mass index categories at or above 50 kg/m² are associated with increased metabolic, hypertensive, and bleeding risks during delivery, a Cureus journal retrospective study published on Sunday reveals.
In Plain English: The Clinical Takeaway
- What it means: Expecting mothers with a booking body mass index of 50 or higher face elevated medical hurdles that demand close monitoring.
- Key risks: The data shows higher rates of gestational diabetes, pre-eclampsia, and postpartum bleeding in this specific patient group.
- Care plan: Early risk assessments and coordinated hospital teams are essential for managing these deliveries safely.
Maternal Complications at Luton and Dunstable Hospital
The single-centre retrospective study examined 124 maternity records at Luton and Dunstable Hospital, reviewing deliveries that occurred between January 2025 and June 2026. Researchers divided the patient cohort into four equal groups of 31 women based on their booking body mass index: normal weight, 30 to 39.9, 40 to 49.9, and 50 or higher. Booking measurements were established at the initial antenatal appointment.
The analysis revealed that women in the highest category, booking a body mass index of 50 kg/m² or greater, experienced the highest rates of pregnancy complications. Specifically, gestational diabetes mellitus affected 32.3% of patients in this group, while pre-eclampsia occurred in 19.3%, and chronic hypertension was recorded in 12.9%. The study also said that gestational diabetes appeared proportionally higher among South Asian/Asian/Middle Eastern and Black/Black African-Caribbean patients.
| BMI Category | Gestational Diabetes | Pre-eclampsia | Caesarean Birth Rate | Postpartum Haemorrhage (>500 mL) |
|---|---|---|---|---|
| Normal (18.5–29.9) | Not specified | Not specified | Not specified | Not specified |
| BMI 30–39.9 | Not specified | Not specified | Not specified | Not specified |
| BMI 40–49.9 | Not specified | Not specified | Not specified | Not specified |
| BMI ≥50 | 32.3% (10/31) | 19.3% (6/31) | 67.7% (21/31) | 61.2% (19/31) |
Delivery Outcomes and Multidisciplinary Care Needs
Surgical delivery rates tracked closely with rising body mass index levels across the hospital cohort. Caesarean sections reached 67.7% for patients in the highest category, with elective caesarean section contributing substantially. Postpartum bleeding exceeding 500 millilitres affected 61.2% of women in the topmost weight tier, alongside a 9.7% wound infection rate.
Despite these operative challenges, the evaluation recorded no instances of venous thromboembolism, blood transfusion, or shoulder dystocia. The authors said that the observational design focused purely on descriptive comparisons rather than establishing direct causation. They emphasized that managing patients with extreme body mass index figures requires multidisciplinary planning across antenatal, intrapartum, and postnatal care.
References
- Kyaw E, Maw S, Phyu M K, et al. Pregnancy Outcomes in Women With High Booking Body Mass Index in a Multi-ethnic Maternity Population: A Single-Centre Retrospective Study. Cureus, 2026; 18(11): e119698.
