Pregnancy-related hysterectomy: a case-control population-based study among 12 INOSS countries
Introduction
Pregnancy-related hysterectomy (PrH) is a life-saving surgical intervention performed when all other medical or surgical options fail to control bleeding. It is considered an obstetric near miss – a condition in which a woman survives a severe complication during pregnancy, childbirth, or within 42 days postpartum. Although rare in high-income countries (fewer than 1 in 1,000 deliveries), PrH is associated with major maternal morbidity and mortality. Known risk factors include advanced maternal age, high parity, abnormal placentation, and current or previous caesarean section. A previous INOSS study across nine European countries revealed a prevalence ranging from 2.6% in Denmark to 10.7% in Italy, as well as considerable variability in the management of obstetric haemorrhage preceding hysterectomy.
Aim
The study is aiming to:
- Update data on the incidence of PrH in participating countries
- Identify key risk factors and maternal outcomes
- Provide evidence-based guidance to clinicians on the appropriateness of hysterectomy indications
Study design
The study is being conducted as a multicountry, population-based case-control study involving 12 INOSS countries:
- Ethiopia
- Italy
- Namibia
- The Netherlands
- Romania
- Slovakia
- South Africa
- Sweden
- United Kingdom
- Finland
- Iceland
- Norway
Case and control definitions
Case: Any woman undergoing surgical removal of the uterus during pregnancy or within 42 days of its outcome.
Control: Women giving birth in participating maternity units during the study period without undergoing hysterectomy, selected in a 2:1 ratio to cases.
Data collection
The study is collecting data on:
- Socio-demographic characteristics
- Medical and obstetric history
- Details of the current pregnancy
- Risk factors, diagnosis, and clinical management
- Maternal and perinatal outcomes Standardised case report forms are being used across countries, with the possibility of adding locally relevant questions.
Data protection
Data are being pseudonymised or aggregated before transfer to the Istituto Superiore di Sanità (Italy), which is coordinating the study. All data handling complies with the EU General Data Protection Regulation (GDPR), and each participating country retains ownership of its data.
Expected impact
By combining high-quality, standardised data from multiple countries, the study is expected to:
Improve understanding of pregnancy-related hysterectomy
Promote best practices in the management of obstetric haemorrhage
Support strategies to reduce maternal morbidity and mortality
