New Diagnosis of Endometriosis is Less Common in Women over Age Forty Presenting with Pelvic Pain.

Study Objective: To investigate the incidence of new diagnosis of endometriosis in women at or above the age of 40 who present with previously undiagnosed pelvic pain and no previous surgical or sonographic evidence of endometriosis to a tertiary care clinic specializing in pelvic pain and endometriosis.

Design: Retrospective cohort study (on the basis of the Strengthening the Reporting of Observational Studies in Epidemiology guidelines) of the incidence of laparoscopically proven endometriosis in women presenting with previously undiagnosed pelvic pain on the basis of age category (age <40 years or ≥40 years). Adjusted odds ratios and 95% confidence intervals were calculated using a multivariable logistic regression model.

Setting: Pelvic pain focused gynecology clinic at a tertiary care hospital.

Patients: Premenopausal women between 18 to 51 years who presented with pelvic pain and were booked for laparoscopy for the diagnosis and the possible treatment of endometriosis between the years 2012 to 2016. Patients who had had previous laparoscopy and those who had sonographic evidence of endometriosis were excluded from the study.

Interventions: Laparoscopic visual evaluation and treatment was carried out in all patients by specialized gynecologists focusing on endometriosis surgery.

Measurements And Main Results: Presence or absence of visualized endometriosis at laparoscopy. We evaluated 174 women who met the inclusion criteria. Endometriosis was diagnosed in 35% (19/55) of patients aged 40 years and above and in 67% (80/119) of patients below the age of 40 years. Odds ratio adjusted for body mass index and parity was 2.38 (1.09-5.00; p = .03). When assessed as a continuous curvilinear variable without division to age categories, age was significant even in the more comprehensive model including more potential confounders. Secondary outcome analysis demonstrated that deep infiltrating endometriosis was diagnosed in 5% (3/55) of the women at or above 40 years and in 8% (10/119) of women below 40 years (p = .76). In addition, a curvilinear relationship was found with age, and there was also a lower incidence of endometriosis of 50% (19/38) in the youngest cohort of women aged 18 to 25 years.

Conclusion: The likelihood of a new diagnosis of endometriosis in women with pelvic pain, no previous laparoscopy and a normal sonogram in our referral center was lower in women aged 40 and above. Careful counseling and consideration of the risks and yield of surgery is recommended before performing a laparoscopy for investigation of pelvic pain in this age group.