BACKGROUND AND PURPOSE:

• Previous studies have found associations between endometriosis or fibroids and adverse pregnancy outcomes
  • However, many of these studies were done in the setting of fertility care and, therefore, are at risk for potential confounding
• Farland et al. (AJOG, 2022) investigated whether women with a history of endometriosis or fibroids had a greater risk for adverse pregnancy outcomes, and whether this risk was impacted by interfertility history

METHODS:

• Retrospective cohort study
  • Linked Delivery data from 3 databases: Society for Assisted Reproductive Technology Clinic Outcome Reporting System (SART CORS) | Massachusetts Pregnancy to Early Life Longitudinal (PELL) data system | Massachusetts all-payer claims database (APCD) 
• Population
  • Deliveries in Massachusetts from 2013 to 2017
• Exposures
  • Endometriosis and fibroid diagnoses before index delivery
  • Subfertility or infertility
  • Use of assisted reproductive technology (ART)
• Study design
  • Relative risks (RRs) adjustments: Pregnancy complications (hypertension, diabetes) |  Maternal Age | BMI | Race and ethnicity | Maternal education | Plurality (singleton, multiple) | Birth year (2013–2017 ordinal categorical calendar years) | Gestational age
• Primary outcome
  • Adverse maternal outcomes (e.g. gestational diabetes, preeclampsia, and placental abnormalities)
  • Adverse pregnancy outcomes (e.g. low birthweight, preterm birth, small for gestational age neonates, cesarean delivery, and prolonged neonatal hospital stay)

RESULTS:

• 91,825 deliveries
  • Endometriosis: 1560 women
    • Experienced sub- or infertility: 30%
    • Utilized ART for index delivery: 34%
  • Fibroids: 4212 women
    • Experienced sub- or infertility: 26%
    • Utilized ART for index delivery: 21%
• Women with a history of endometriosis were at a greater risk for
  • Pregnancy-induced hypertension, preeclampsia, or eclampsia
    • Endometriosis: RR 1.17 (95% CI, 1.03 to 1.33)
  • Placental abnormalities
    • Endometriosis: RR 1.65 (95% CI, 1.33 to 2.06)
    • Fibroids: RR 1.38 (95% CI, 1.19 to 1.60)
  • Cesarean delivery
    • Endometriosis: RR 1.22 (95% CI, 1.15 to 1.29)
    • Fibroids: RR 1.17 (95% CI, 1.13 to 1.21)
• Neonates born to women with a history of endometriosis or fibroids were also at a greater risk for preterm birth
  • Endometriosis: RR 1.24 (95% CI, 1.09 to 1.41)
  • Fibroids: RR 1.17 (95% CI, 1.07 to 1.29)
• Endometriosis and associated risk for placental abnormalities varied by fertility history
  • Risk was not but statistically significant when restricted to noninfertile women
• Associations between fibroids and low birthweight varied by fertility status or assisted reproductive technology
  • Associations were stronger among noninfertile women
  • Results attenuated among subfertile or infertile women and women who utilized ART

CONCLUSION:

• Endometriosis and fibroids were associated with increased risk for adverse maternal outcomes such as hypertension, preeclampsia, and cesarean delivery, and were also associated with an increased risk of preterm birth
• The authors state

Women with a history of endometriosis and fibroids may have a greater risk for certain adverse pregnancy outcomes when compared with women without a history of these conditions

Additional research is needed to investigate whether pregnant women with a history of endometriosis or fibroids can benefit from increased screening or intervention during pregnancy before these findings can be used in clinical settings 

Learn More – Primary Sources:

Pregnancy outcomes among women with endometriosis and fibroids: registry linkage study in Massachusetts

Related ObG Topics:

Is Preterm Birth More Common in Women with Endometriosis? 

Is There a Link Between Endometriosis and Adverse Pregnancy Outcomes?

Are Fibroids Associated with Miscarriage?

Are Fibroids Associated with an Increased Risk for Preterm Birth?