Lab study, 2025
Does the protein HIF2A cause heavy menstrual bleeding?
A laboratory study suggests that high HIF2A levels in the uterus may slow down healing and be linked to heavier bleeding, but HIF2A alone probably does not cause heavy bleeding. Limiting HIF2A levels may help the uterus work better during menstruation.
What they did
Researchers compared uterus tissue from women with heavy menstrual bleeding to women with normal bleeding. They also studied mice engineered to have different HIF2A levels to see how it affected bleeding and how quickly the uterus repaired.
What they found
Women with heavy bleeding had higher HIF2A levels. In mice with less HIF2A, 88% had complete repair within 24 hours compared to 65% of normal mice. Bleeding measured 0.39 microliters versus 0.98 microliters. When researchers increased HIF2A before menstruation, only 11% had early repair compared to 30% of controls.
What it means for you
This is a laboratory and animal study, not testing in women. It suggests a possible mechanism but does not prove HIF2A causes heavy bleeding or that reducing it would help women. The findings are preliminary.
88%
mice with reduced HIF2A that had complete repair within 24 hours
0.39 microliters
blood loss in mice with reduced HIF2A
0.98 microliters
blood loss in normal mice
About the study
- Original title
- Limiting Premenstrual Endometrial Hypoxia Inducible Factor 2 Alpha May Fine-Tune Endometrial Function at Menstruation
- Authors
- Martínez-Aguilar R, Rowley BM, Walker C et al.
- Journal
- The Journal of clinical endocrinology and metabolism
- Year
- 2025
- Study design
- Lab study
- What was tested
- Genetic or chemical modification of HIF2A levels in mice
- Open access
- Yes
- Read the paper
- doi.org/10.1210/clinem/dgae630
Original abstract
Context: Heavy menstrual bleeding (HMB) is common and debilitating, but the precise endometrial mechanisms causing increased menstrual blood loss (MBL) remain undefined. We have previously identified a role for hypoxia in endometrial repair following progesterone withdrawal. Objective: As hypoxia inducible factor 2 alpha (HIF2A) is known to alter vascular function in other tissues, we hypothezised that endometrial HIF2A is involved in premenstrual optimization of endometrial function during the secretory phase to limit MBL. Results: Women with objective HMB had higher endometrial HIF2A during the mid-secretory phase when compared to those with normal MBL (P = 0.0269). In a mouse model of simulated menses, genetic or pharmacological manipulation of HIF2A did not significantly affect endometrial breakdown/repair, volume of MBL or endometrial hypoxia. However, 88% of Hif2a heterozygote mice reached early-full repair by 24 hours vs only 65% of wild-type mice. Mean MBL was 0.39 μL (±0.67) in Hif2a heterozygote mice vs 0.98 μL (±0.79) in wild-type mice. Conversely, when we increased HIF2A before menstruation, 11% reached early repair by 8 hours vs 30% of vehicle-treated mice. Mean MBL was 2.61 μL (±1.10) in mice with HIF2A stabilization and 2.24 μL (±1.14) in vehicle-treated mice. These nonsignificant but consistent trends indicate that increased endometrial HIF2A may contribute to delayed endometrial repair and HMB. Conclusions: Increased HIF2A in the secretory endometrium is unlikely to be sufficient to account for the phenotype of HMB, but limitation of HIF2 levels may optimize endometrial function at menstruation.
Reproduced under CC-BY.