In another thread, there was some debate about the "male brain". This got me to thinking about the differences in male and female brains. This is one of the most interesting things I found :10 Things Every Man Should Know about a Woman's Brain | LiveScience #9 REALLY made sense to me.. She goes through adolescence twice No one wants to go through adolescence again. Its physical changes and hormonal fluctuations not only create mood swings and physical discomfort but nagging questions about self-identity as well. Women, however, lucky girls, get to do just that. They go through a "second adolescence" called perimenopause in their 40s. It starts around age 43 and reaches its pinnacle by 47 or 48 years old. (Men's hormones also change as they age, but not nearly as abruptly.) In addition to erratic periods and night sweats, a woman's hormones during this transition are so crazed she can be as moody as a teenager. The duration of perimenopause varies from two to nine years, with most women leaving it behind by age 52. " At last I know what the fuck's been going on with me for the past 4 years and that it's normal.