Menstrual fluid endometrial stem/progenitor cell and supernatant protein content: cyclical variation and indicative range

In plain language

Eleven women with regular cycles collected menstrual fluid in a menstrual cup on day 2 of up to five cycles, and the endometrial stem and progenitor cells and proteins in it were measured over time. These cells were shed in menstrual fluid and could form colonies, and their proportions, along with five of eight endometrial proteins, varied relatively little between cycles in the same woman (intraclass correlation 0.52 to 0.75 for cells, 0.57 to 0.69 for proteins).

Key numbers

11

Women, sampled over up to five cycles

ICC 0.75

Cycle-to-cycle agreement for SUSD2+ endometrial stem cells

5 of 8

Proteins with moderate cycle-to-cycle agreement

What it means

If menstrual fluid is fairly consistent month to month, a single sample may be enough to characterize it, a practical prerequisite for any menstrual test. The authors also saw outliers, some of whom reported menstrual problems.