Exploring the risks of postpartum infections: Insights from labor induction practices

Abstract

Sir,

We read with great interest the article by Hogh-Poulsen et al. titled “Maternal postpartum infection risk following induction of labor: A Danish national cohort study” published in Acta Obstetricia et Gynecologica Scandinavica (2025).¹ The study provides valuable insights into the association between induction of labor (IOL) and maternal postpartum infection risk, particularly in a large, nationwide cohort. The study included a substantial number of deliveries (n = 546 864) over an 11-year period, providing robust statistical power to detect associations between IOL and postpartum infections. The use of national registries ensured a comprehensive dataset, including both hospital discharge diagnoses and antibiotic prescriptions, which captures both severe and mild infections. However, we would like to highlight several aspects of the study that warrant further discussion and consideration.

First, while the study demonstrates an association between IOL and postpartum infections, it cannot establish causality. The authors acknowledge this limitation, but it is important to emphasize that unmeasured confounders, such as the specific methods of IOL (e.g., Foley catheter vs. prostaglandins), could influence the results. Future studies should aim to explore these factors to better understand the mechanisms behind the observed associations.

Second, the study found that women with rupture of membranes (ROM) prior to IOL were not at increased risk of infection, which may reflect effective clinical management, such as the use of prophylactic antibiotics.² However, the study did not have data on antibiotic prophylaxis, which could be a significant confounder. Including this information in future research would provide a more complete picture of the factors influencing postpartum infection risk.

Third, the study focused on infections within 30 and 60 days postpartum, which aligns with the WHO definition of the postpartum period. However, some infections, particularly those related to surgical sites or endometritis, may manifest or persist beyond this timeframe.³ Extending the follow-up period could provide additional insights into the long-term consequences of IOL.

In conclusion, the study by Hogh-Poulsen et al. is a significant contribution to the literature on maternal health, particularly in understanding the risks associated with IOL. The findings suggest that IOL is associated with a modest increase in postpartum infection risk, but the absolute risk remains low. However, the study also highlights the need for further research to explore causality, the role of prophylactic antibiotics, and the generalizability of these findings to other populations. We commend the authors for their rigorous methodology and encourage future studies to build on these findings to optimize clinical practices and improve maternal outcomes.