Menstrual cycle phases and acne flares: A retrospective analysis in Indian women

Background: Acne vulgaris is a common skin disorder that impacts quality of life. Both acne and menstrual symptoms share a hormonal pathogenesis, often linked to hormonal imbalances in women. This suggests a relationship between acne counts and the various phases of the menstrual cycle. Objective: In this study, we aimed to assess the relationship between acne counts and the menstrual cycle in healthy young Indian women suffering from mild to moderate acne. The objective was to further understand the role of the various phases of the menstrual cycle in acne flares. Methods: This study explores the data from two (2) previously conducted clinical trials. The studies originally aimed to evaluate the efficacy of topical creams in the reduction of acne lesion count on the face. The data from these studies were retrieved and compiled. The number of days between the last menstrual period (LMP) and the actual day of the visit was calculated and regrouped as follows: 1–7 days (early to mid-follicular phase), 8–15 days (mid- to late follicular phase), 16–24 days (post-ovulation to early luteal phase) and > 24 days (mid- to late luteal phase). Subsequently, the global acne count — recorded by the dermatologist as part of the study procedures — was cross-tabulated with these menstrual phases using measures of central tendency and dispersion, followed by inferential analyses to evaluate differences between groups. Results: On average, the female subjects visiting the centre during the end of their luteal phase or bleeding days had higher acne counts (p = 0.032). This effect was statistically significant only at the baseline visit, which followed a 14-day washout period involving the use of a neutral cleanser and adoption of a general skincare routine. During the product use phase, the effect of the menstrual cycle diminished. Conclusion: The study demonstrates an association between acne flares and the menstrual cycle: acne counts are likely to be higher by an average of 5–6 units during the late luteal and early follicular phases. Such differences may impact the outcome of clinical trials if not carefully monitored and accounted for in study designs and data analysis.