most woman get there period 28 days after they last had it.
Girls get periods and they have it so that while ovulating (getting her period) and has sex she can become pregnant. Men don't have periods because they carry sperm to help get a woman pregnant. And you know that men can't have babys.
The average menstrual cycle is 28 days long, but everyone is different. Many women will have cycles that are a lot longer than average, it's also normal for there to be up to a weeks variation between cycles or if a woman has irregular cycles she may have longer cycles and shorter cycles. There are also girls who do not have periods at all because they don't have the correct anatomy.
Yes, it often does
You can only get pregnant if you are having your periods and you start your periods some time during puberty. (Ask a woman in your family about periods if you don't know what they are) In some cases your periods can start as early as nine years old but the norm (i think) is about 10 - 13 years. Don't worry if you start early or late though, the 'norm' is just the average. I wont explain about puberty because you are asking this question so you probably already know
Activational hormone effects can happen at any time during adulthood and often occur over short periods of time. They are often transient or reversible. These are different than organizational hormone effects, which occur during specific periods in development, have permanent or long-lasting effects, and help to set up the brain for later interactions with hormones.
Once every 6 MBY.
Your body might not be able to produces the hormones necessary for menstruation. Many women in Africa or anorexic girls do not have their periods as often as they should. This is due to a lack of health. Their bodies don't produces the hormones so they don't have periods as often.
A woman's menstrual periods are regular and usually lighter when she is taking oral contraceptives
A woman can get her period twice a month if she has irregular periods.
the same as someone who has regular periods. having periods, in general, means that your body can have babies.
They start during puberty
a woman can get pregnant with a baby the FIRST time she EVER has SEX even if she has NO PERIODS! and you are at risk of getting pregnant always. use birth control
Generally while woman are breastfeeding they do not have periods.
A young woman is consider to be just that from her teens but often called a woman. A young woman is considered 'a woman' when she starts her menstrual periods, but it is wisdom that makes her a true woman. No, it is not insulting to call a woman 'a woman of a certain age' but it is an insult if the woman of 50 or up is called an older to old woman or elderly woman.
If pregnancy may be in periods
No, a woman cannot still have menstrual periods after a hysterectomy. Menstruation is the shedding of the uterine lining, if there's no more uterus there's no more menstruation.
Women living with each other for a prolonged periods of time tend to have periods that coincide with each other. It is proposed that pheromones are the cause of that.