Obstetric and non-obstetric surgery during pregnancy: A 20-year Danish population-based prevalence study

OBJECTIVES: Population-based studies on use of non-obstetric and obstetric surgical procedures during pregnancy are sparse. Therefore, our objective was to estimate the prevalence of surgery during pregnancy, including potential time trends, overall and by trimester and describe the characteristics of pregnant women undergoing surgery. DESIGN: This study is a large nationwide cohort study. SETTING: From administrative and medical databases, we obtained information about all pregnancies ending in a live birth, a stillbirth or an abortion (spontaneous and induced) in Denmark during 1996–2015. Procedures (excluding caesarean sections) conducted during pregnancy were categorised as a non-obstetric or obstetric surgery and further divided into laparoscopic or non-laparoscopic procedures. MAIN OUTCOME MEASURE: Main outcome measure is prevalence of surgery during pregnancy. RESULTS: We included 1 687 176 pregnancies of which 108 502 (6.4%) received 117 424 surgical procedures. The prevalence of non-obstetric surgery was almost stable (1.5% in 1996–1999 to 1.6% in 2012–2015), whereas non-obstetric abdominal or gynaecological laparoscopic procedures increased from 0.5% to 0.8%. For appendectomies, the proportion of laparoscopic surgery increased from 4.2% to 79.2% during the study period. In 49 pregnancies, surgery for internal herniation was conducted in 2012–2015 versus none in 1996–1999. The prevalence of obstetric surgery, excluding invasive diagnostic tests, increased from 0.2% to 0.8%. High multiplicity, smoking, increasing age, body mass index (BMI) and parity were factors associated with a high prevalence of surgery during pregnancy. CONCLUSIONS: The increase in the prevalence of laparoscopic surgery during pregnancy may reflect a decreased restraint concerning conductance of these surgical procedures during pregnancy. The increasing proportion of laparoscopic procedures complies with clinical recommendations, and the prevalence of surgery during pregnancy varied by multiplicity, smoking status, parity, age and BMI.