An Apple Women’s Health Study has established a link between obesity and abnormal uterine bleeding patterns (AUB), noting that those with higher body mass index would experience a higher prevalence of extended menstruation than those who are not.
The findings, which were published in the American Journal of Obstetrics and Gynecology, collected self-reported cycle-tracking data from 18,875 participants’ from November 2019 through July 2021.
The participants’ average age was 33 and their average BMI was 29.3.
Abnormal uterine bleeding is bleeding between monthly periods, prolonged bleeding or an extremely heavy period. Possible causes include fibroids, polyps, hormone changes and — in rare cases — cancer.
Respondents to the poll attested to the correctness of the data from the prior months, which were then used to certify monthly monitoring.
Participants reported irregular menstruation in 2.9% of cases, infrequent menstruation in 8.4% of cases, protracted menstruation in 2.3% of cases, and irregular intermenstrual bleeding in 6.1% of cases (spotting).
Respondents who reported having polycystic ovarian syndrome, endometriosis, hyperthyroidism, or hypothyroidism were more likely to report having abnormal uttering bleeding than those who did not.
In comparison to white, non-Hispanic individuals, black participants had a 33% higher prevalence of irregular menses and were more likely to report having abnormal uterine bleeding. More Asian individuals experienced irregular periods.
Compared to people of a healthy weight, the results of the study showed that those who are obese (with a BMI over 40) are 94% more likely to have extended periods, and 18% more likely to have abnormal uterine bleeding.
“Overall, these findings provide the rate of AUB in a large, digital dataset of confirmed menstrual tracking. In addition to expanding our understanding of AUB across a diverse population, our findings confirm existing literature on the associations between AUB and medical conditions,” the researchers wrote.
The analysis’ shortcomings were highlighted by the researchers. Using an iPhone as a study platform might prevent results from generalising to a bigger population. Additionally, they discovered that research participants were more likely to have a college degree and that the study’s ethnic demographics did not accurately reflect the greater U.S. population.
However, the study’s authors said that the findings broadened understanding of abnormal bleeding among a vast and varied group without being constrained by reproductive objectives, medical backgrounds, or specific clinical settings.
“This study builds on previous cohort data by adding diversity and extends modern datasets derived from menstrual tracking apps by collecting contextual information related to demographics and medical histories,” researchers wrote.
