Endometriosis and preterm birth: A Danish cohort study

Area of Science:

• Reproductive Medicine
• Obstetrics
• Epidemiology

Background:

• Endometriosis is increasingly linked to a higher risk of preterm birth.
• The specific pathways mediating this association remain unclear.
• Understanding these pathways is crucial for improving pregnancy outcomes in women with endometriosis.

Purpose of the Study:

• To investigate the association between endometriosis and different pathways of preterm birth.
• To examine these associations across various gestational ages.
• To differentiate between medically indicated preterm birth, premature pre-labor rupture of membranes (PPROM), and spontaneous labor contractions.

Main Methods:

• A population-based cohort study linking multiple Danish health registries.
• Inclusion of singleton pregnancies from the Aarhus Birth Cohort.
• Analysis of endometriosis status, preterm birth (before 37 and 32 weeks), and specific preterm birth pathways.

Main Results:

• Women with endometriosis showed increased risks for overall preterm birth (aHR 1.6) and very preterm birth (aHR 1.8).
• Medically indicated preterm birth was more prominent before 37 weeks (aHR 2.4) in women with endometriosis.
• Spontaneous preterm birth was more common before 32 weeks (aHR 2.2), with a heightened risk of PPROM before 32 weeks in those with verified endometriosis (aHR 3.49).

Conclusions:

• Endometriosis is associated with increased risks of both preterm and very preterm birth.
• The pathways differ: medically indicated preterm birth before 37 weeks and spontaneous preterm birth before 32 weeks are more prevalent.
• These findings highlight the complex relationship between endometriosis and adverse pregnancy outcomes, necessitating targeted interventions.