Dr. Jerilynn C. Prior and the UBC Centre for Menstrual Cycle and Ovulation Research are studying persons who have been diagnosed with Endometriosis (EndoM) and healthy, normally menstruating women+. This unique new study will bring new insights into women’s health.

For the first time ever, we will test Brown Adipose Tissue (BAT) activity in persons diagnosed with endometriosis.

PURPOSES OF THE STUDY

The main goal of this research is to measure BAT activity in persons with EndoM and similar controls during the early part of the cycle (follicular phase) and following egg release (ovulation). We will determine whether BAT activity in persons with EndoM differs from healthy control women+ who are of similar age, weight and menstrual cycle characteristics.

WHAT DOES THE STUDY INVOLVE?

This study asks participants to come in person to the CeMCOR office (near Vancouver General Hospital) twice in three cycles for measurement of BAT activity and finger-prick blood tests. To be part of this new and novel study, we need you to complete some questionnaires, take your morning temperatures and keep the Menstrual Cycle Diary© for two cycles.

WHAT ARE WE MEASURING AND HOW?

• This BAT study is over two-plus full menstrual cycles and the start of a third. BAT activity is stimulated by becoming cool, and assessed by thermal imaging above both collar bones with an infrared camera. We will measure BAT twice in different menstrual cycle phases.
• You will learn to record Menstrual Cycle Diary© (Diary) experiences, and take your first morning temperature (from which we can assess ovulation and the luteal phase length) every day for over two-plus menstrual cycles.
• You will record everything you eat and drink for a weekend and two week-days and other questionnaires about appetite and eating.
• We will ask questions about your health, cycles, exercise and habits and twice do finger-pricks for blood spot analysis of estrogen, progesterone and testosterone
• The first 20 volunteers with complete data in the EndoM and control groups may also have Dual X-ray Absorptiometry (DXA), measurement of whole-body fat, muscle and bone.

WHEN IS THE STUDY STARTING AND HOW LONG IS IT?

We will be recruiting healthy control participants until January 2026. We are hoping to have learned the main study results by the end of March 2026. 

STUDY PARTICIPANTS

We have successfully enrolled and studied 13 participants with endometriosis and are now studying 13 healthy controls who match the group.

STUDY ELIGIBILITY (CONTROL GROUP)

✅ Not diagnosed with Endometriosis
✅ 22–41 years old
✅ Have regular, month-apart cycles (21–35 days long)
✅ Body Mass Index (BMI) under 26 (BMI=weight/height2)
✅ Self-identity as one of these ethnicities: East Asian, South Asian, South American, or White
✅ Living in Metro Vancouver

Participants will complete screening to confirm ovulatory cycles for eligibility.

PERKS OF PARTICIPATING

Participants will be thanked for their time and conscientious efforts by being given a gift card for each in-person visit (total 2).

Finally, at the end of the study, we will give you a novel about perimenopause that Dr. Prior wrote and CeMCOR published to help prepare you for what’s ahead.

If you wish, we will also give you an appropriately sized menstrual cup (donated by DivaCup) so you can conveniently manage menstruation while decreasing the environmental risks and the costs of pads and tampons.