COVID-19 vaccination not linked to abnormal uterine bleeding

COVID-19 vaccination not linked to abnormal uterine bleeding | Image Credit: © Kiattisak – © Kiattisak – stock.adobe.com.

COVID-19 vaccination availability is not associated with medically attended abnormal uterine bleeding (AUB) incidence among reproductive-aged women, according to a recent study in the American Journal of Obstetrics & Gynecology.¹

Data has indicated short-term effects from COVID-19 vaccination on menstrual symptoms such as menstruation timing, duration, flow, and pain. This can lead to anxiety about reproductive health and quality of life. However, there is not enough data to determine if these changes should lead to increased health care visits.

Small variations in cycle timing or flow may not lead individuals to seek medical care. However, AUB diagnoses may be used to indicate concerning or bothersome changes in uterine bleeding.

The Centers for Disease Control and Prevention recommend individuals with bleeding for more than 7 days or heavy enough they need to change their tampon every hour speak with a health care provider.² Heavy bleeding can lead to anemia and significantly impact quality of life.

Investigators conducted a study to determine the impact of COVID-19 vaccination on AUB diagnoses and medical care.¹ Data was obtained from the Kaiser Permanente Northwest (KPNW) site. KPNW members aged 16 to 44 years with International Classification of Diseases, Tenth Revision (ICD-10) codes for AUB were included in the analysis.

ICD-10 codes for AUB included excessive and frequent bleeding with regular cycle, excessive and frequent menstruation with irregular cycle, ovulation bleeding, excessive premenopausal bleeding, other specified irregular menstruation, unspecified irregular menstruation, other specified abnormal uterine and vaginal bleeding, and unspecified abnormal uterine and vaginal bleeding.

AUB diagnoses were measured per 100,000 individuals monthly between January 2018 and December 2021. Changes in diagnosis following availability of the COVID-19 vaccine were measured through conducted segmented regression analyses of the December 2020 to December 2021 period.

Diagnoses from February 2020 to December 2020 were excluded because of challenges accessing health care during the COVID-19 pandemic. Overall rates and rates by age group were evaluated.

Cohorts included patients who had not received any COVID-19 vaccine before the index diagnosis, patients who received a COVID-19 vaccine within 60 days before the index diagnosis, and patients who received a COVID-19 vaccine before the index diagnosis but not within 60 days. The index data was the encounter when a patient received their first postvaccination AUB diagnosis.

Clinical characteristics included setting of initial code, hospital or emergency department (ED) visit with an AUB code, receipt of iron infusion or intravenous fluids, and dilation and curettage procedure. Demographic characteristics included race, ethnicity, and age.

There were 79,000 to 85,000 participants per month included in the analysis, with no significant change in AUB incidence trends between the prepandemic and postvaccine periods. This trend was observed across all age categories.

Significant differences in age, race, ethnicity, and ED or inpatient diagnosis were reported based on vaccination status. Postvaccination AUB was reported for 28% of cases.

The most common symptom reported in postvaccination AUB cases was change in bleeding timing. A single AUB episode was reported in 59.6% of cases and resolution by the time of review in 82.5%. Use of a hormonal contraceptive or copper intrauterine device at the index date was reported by 48% of cases.

When evaluating bleeding etiologies, no cases were linked to COVID-19 vaccination. Fourteen percent of vaccine cases asking if the AUB was linked to vaccination had a documented bleeding etiology, and 78.6% received additional COVID-19 vaccine doses after AUB diagnosis.

These results indicated no association between COVID-19 vaccination and AUB. Investigators recommended future research follow-up on the available descriptive analysis of AUB following COVID-19 vaccination.

References

1. Brooks N, Irving SA, Kauffman TL, et al. Abnormal uterine bleeding diagnoses and care following COVID-19 vaccination. Am J Obstet Gynecol. 2024;230:540.e1-13. doi:10.1016/j.ajog.2024.01.006
2. About heavy menstrual bleeding. Centers for Disease Control and Prevention. Accessed May 21, 2024. https://www.cdc.gov/female-blood-disorders/about/heavy-menstrual-bleeding.html#:~:text=If%20you%20have%20bleeding%20that,talk%20with%20your%20healthcare%20provider.