Uterine cervical conisation and chorioamnionitis: A nationwide observational study

Area of Science:

• Obstetrics and Gynecology
• Perinatal Medicine
• Reproductive Health

Background:

• Cervical conisation is a procedure to treat precancerous cervical changes.
• The potential impact of conisation on pregnancy outcomes, specifically chorioamnionitis (CAM) and preterm birth (PTB), requires further investigation.

Purpose of the Study:

• To determine if conisation increases the incidence of CAM.
• To assess if the risk of CAM following conisation differs between preterm and term pregnancies.
• To estimate the mediating role of CAM in the association between conisation and PTB.

Main Methods:

• Nationwide observational study in Japan (2013-2019) using perinatal registry data.
• Analysis of singleton pregnancies, comparing women with and without a history of conisation.
• Multivariable logistic regression and mediation analysis to assess associations and effects.

Main Results:

• Conisation was associated with a significantly higher risk of clinical CAM (OR 3.09).
• This association was pronounced in preterm pregnancies but not significant in term pregnancies.
• Conisation increased the risk of PTB, with CAM mediating a small proportion (5.9%) of this effect.

Conclusions:

• Conisation is linked to an increased occurrence of CAM.
• Healthcare providers should monitor for CAM in women with a history of conisation, especially during the preterm period.
• Bacterial infections, potentially related to CAM, may be a key factor in PTB after conisation.