Basic survey of menstrual cycle

目前日本妇女正常月经的定义是根据1962年进行的调查得出的。它的定义如下；正常周期：25-38天，周期变化≤6天，卵泡期：17.9±6.2天，黄体期：12.7±1.6天，月经量：5-7天。月经周期的长短和变化受人体测量、营养和女性种族的影响。由于40多年来月经周期可能发生变化，正常月经周期的定义需要重新评估。了解月经周期的长度和变化对于评估月经不规律是必要的。我们要求120名健康妇女记录其基础体温至少6个月。我们的调查结果如下：正常周期：26-38天（平均31.1±5.9天），周期变化≤5天，卵泡期：19.1±5.6天，黄体期：11.9±2.2天，月经量：5-7天。除了卵泡期和黄体期的平均持续时间外，我们的重新评估没有影响目前的定义。卵泡期延长1.2天，黄体期缩短0.8天。在过去的40年里，这些发现进展缓慢，其意义仍然模糊不清。尽管日本女性的生活方式是西方的，但与高加索女性相比，日本女性的月经周期平均延长了3天。月经周期的缩短意味着一生中月经周期的增加，说明白种人女性雌激素暴露程度较高。

The present definition of normal menstruation for Japanese women was based on the survey carried out in 1962. The definition of that is in the following ; regular cycle : 25-38 days, cycle variation : less than or equal 6 days, follicular phase : 17.9±6.2 days, luteal phase : 12.7±1.6 days, menstrual flow : 5-7 days. The length and variation of menstrual cycle is under the influence of anthropometry, nutrition, and race of women. Because of possible variation of the menstrual cycle in over 40 years, the definition of normal menstrual cycle needs re-evaluation. Knowledge of the length and variation of the menstrual cycle is necessary for the assessment of menstrual irregularities.We asked 120 health women to record her basal body temperature at least for 6 months. The results of our survey are in the following ; regular cycle:26-38 days(mean 31.1±5.9 days), cycle variation : less than or equal 5 days, follicular phase : 19.1±5.6 days, luteal phase : 11.9±2.2 days, menstrual flow : 5-7 days. With the exception of the mean duration of follicular and luteal phase, our re-evaluation did not affect the present definition. The follicular phase is prolonged 1.2 day, and the luteal phase is shortened 0.8 day. Those findings have taken place slowly over the past 40 years, and its significance remains obscure. Despite the western life style, the mean length of menstrual cycles in Japanese women is prolonged for 3days compared with those of Caucasian women. The shortened menstrual cycle means increased menstrual cycles in the life, suggesting high exposure of estrogen in Caucasian women.