Endometriosis and Risk of Adverse Pregnancy Outcomes

Leslie V Farland; Prescott J; Sasamoto N; Tobias DK; Audrey J Gaskins; Stuart JJ; Carusi DA; Jorge E Chavarro; Andrew Horne; Rich-Edwards JW; Stacey A Missmer

doi:10.1097/aog.0000000000003410

Endometriosis · Fertility and Outcomes

Endometriosis and Risk of Adverse Pregnancy Outcomes

Farland LV, Prescott J, Sasamoto N, Tobias DK, Gaskins AJ, Stuart JJ, Carusi DA, Chavarro JE, Horne AW, Rich-Edwards JW, Missmer SA

Published September 2019 Obstetrics & Gynecology, 134(3), 527-536

DOI 10.1097/aog.0000000000003410 PMC PMC6922084

RRM Academy Synopsis

Endometriosis is linked to more miscarriage and ectopic pregnancy

A study of 116,429 U.S. nurses found that women with laparoscopically confirmed endometriosis had more miscarriages and ectopic pregnancies. About 19 out of 100 pregnancies with endometriosis ended in miscarriage. Without it, about 12 out of 100 did.

Key Findings

Miscarriage (spontaneous abortion): 1,714 of 8,875 pregnancies (19.3%) with endometriosis versus 23,150 of 187,847 (12.3%) without. Multivariable-adjusted RR 1.40, 95% CI 1.31–1.49.
Ectopic pregnancy: 157 of 8,875 pregnancies (1.8%) with endometriosis versus 1,529 of 187,847 (0.8%) without. Multivariable-adjusted RR 1.46, 95% CI 1.19–1.80.
Gestational diabetes (GDM): 4.3% versus 3.0%, RR 1.35, 95% CI 1.11–1.63. Hypertensive disorders of pregnancy: 9.5% versus 6.6%, RR 1.30, 95% CI 1.16–1.45.
Suggested association with preterm birth: 12.0% versus 8.1%, RR 1.16, 95% CI 1.05–1.28. Low birth weight: 5.6% versus 3.6%, RR 1.16, 95% CI 1.03–1.29.
Suggested association with stillbirth: 1.9% versus 1.4%, RR 1.27, 95% CI 1.01–1.60. The authors advise cautious reading because of the small sample; the 99% CI was 0.94–1.72.

Interpretation

The Nurses' Health Study II is an observational cohort. Its results show an association and cannot show that endometriosis causes these outcomes. Women reported their own pregnancy outcomes. Also, 77% of pregnancies came before enrollment in 1989, so the authors assumed women diagnosed before then were exposed in those earlier pregnancies. Recall of pregnancy loss has not been validated in this population. Endometriosis stage and biopsy results were unavailable, and some outcomes had few events. The gestational diabetes link weakened when analyses used only pregnancies after 1989.

RRM Context

Restorative reproductive medicine treats endometriosis as a disease that lasts through the reproductive years. This cohort adds pregnancy outcomes to that picture. The authors report a diagnostic delay of about 4 years in this cohort and about 7 years in international studies. The paper reports no analysis of surgery or other treatment, so any effect of removing disease on these risks is unmeasured.

Our editorial summary of this paper, not the article's abstract.

Abstract

Objective

To investigate the relationship between endometriosis and adverse pregnancy outcomes.

Methods

Women between ages 25 and 42 years in 1989 (n=116,429) reported detailed information on pregnancies and reproductive health at baseline and every 2 years thereafter in the Nurses' Health Study II, a cohort study. In 2009, they completed a detailed, pregnancy-focused questionnaire. A total of 196,722 pregnancies were reported. Adverse pregnancy outcomes included spontaneous abortion, ectopic pregnancy, stillbirth, gestational diabetes mellitus (GDM), hypertensive disorders of pregnancy (preeclampsia or gestational hypertension), preterm birth, and low birth weight. We estimated the relative risks (RRs) and 95% CIs of adverse pregnancy outcomes comparing pregnancies in women with and without a history of laparoscopically confirmed endometriosis using multivariable log-binomial regression, with generalized estimating equations to account for multiple pregnancies per woman.

Results

Endometriosis was associated with a greater risk of pregnancy loss (spontaneous abortion: RR 1.40, 95% CI 1.31–1.49; ectopic pregnancy: RR 1.46, 95% CI 1.19–1.80). Endometriosis was also associated with a greater risk of GDM (RR 1.35, 95% CI 1.11–1.63) and hypertensive disorders of pregnancy (RR 1.30, 95% CI 1.16–1.45).

Conclusions

We observed an association between laparoscopically confirmed endometriosis and several adverse pregnancy outcomes. Future research should focus on the potential biological pathways underlying these relationships to inform screening or preventive interventions.

Topics

Endometriosis › Fertility and Outcomes › Conception After Excision · Pregnancy › Pregnancy Complications › Gestational Diabetes · Birth and Delivery › Birth Outcomes › Maternal Morbidity

Leslie V Farland, Audrey J Gaskins, Jorge E Chavarro, Andrew Horne, Stacey A Missmer

L Farland, A Gaskins, J Chavarro, Andy Horne, Drew Horne, A Horne, S Missmer

DOI 10.1097/aog.0000000000003410 10.1097/aog.0000000000003410 Farland et al. 2019, Farland 2019

Endometriosis and Risk of Adverse Pregnancy Outcomes

Endometriosis is linked to more miscarriage and ectopic pregnancy

Key Findings

Interpretation

RRM Context

Abstract

Topics

By this author

Related research