Department of Public Health, Central Michigan University, Mt Pleasant MI 48859, USA.
Medicina (Kaunas). 2020 Apr 10;56(4):173. doi: 10.3390/medicina56040173.
: The purpose of this project is to evaluate the association between twin sex discordance and menstrual characteristics. We hypothesize that sharing the uterus with a male twin can change ovulation programming, hence changing the menstrual cycle characteristics during adulthood. This project could be novel in discovering new physiological mechanisms of hormone exposure and menstrual cycles. : This is a cross-sectional study. We asked females from sex-concordant ( = 1290) and sex-discordant ( = 168) twin pairs in the Washington State Twin Registry about characteristics of menstrual cycles. Generalized Estimating Equation (GEE) analysis was used to compare groups. The main outcome measures included the amount of bleeding, duration of menstruation, the timing of menstruation, length of menstruation, and a number of periods per year. : We found a statistically significant association between the amount of menstrual period bleeding and twin sex discordance (0.42 (95% CI 0.18-0.94)). However, twin sex discordance was not associated with period duration, length of menstrual cycle, cycle regularity, or a number of periods per year. : Twin sex discordance is not a predictor of clinical characteristics of menstruation during adulthood except for the amount of bleeding. Future studies should focus on the impact of male hormones on the amount of bleeding during menstruation.
: 本研究旨在评估同卵双生子性别不一致与月经特征之间的关系。我们假设与男性同卵双生子共享子宫会改变排卵编程，从而改变成年期的月经周期特征。本研究可能在发现激素暴露和月经周期的新生理机制方面具有创新性。 : 这是一项横断面研究。我们询问了华盛顿州双胞胎登记处中同性别（=1290）和性别不一致（=168）的双胞胎女性有关月经周期特征的问题。使用广义估计方程（GEE）分析比较了组间差异。主要结局指标包括出血量、经期持续时间、经期时间、经期长度和每年的经期次数。 : 我们发现月经期间出血量与同卵双生子性别不一致之间存在统计学显著关联（0.42（95%CI 0.18-0.94））。然而，同卵双生子性别不一致与经期持续时间、月经周期长度、周期规律性或每年经期次数无关。 : 除了出血量外，同卵双生子性别不一致不是成年期月经临床特征的预测因素。未来的研究应集中在男性激素对月经期间出血量的影响。
