These hormones cause the lining of the uterus or womb to build up. The built-up lining is ready for a fertilized egg to attach to and start developing. If there is no fertilized egg, the lining breaks down and bleeds. Then the same process happens all over again. It usually takes about a month for the lining to build up, then break down.
That is why most girls and women get their periods around once a month. Ovulation pronounced: ov-yoo-LAY-shun is the release of an egg from the ovaries. The same hormones that cause the uterus lining to build up also cause an egg to leave one of the ovaries.
The egg travels through a thin tube called a fallopian tube to the uterus. If the egg is fertilized by a sperm cell, it attaches to the wall of the uterus, where over time it develops into a baby. If the egg is not fertilized, the uterus lining breaks down and bleeds, causing a period. For the first few years after a girl starts her period, it may not come regularly.
This is normal at first. By about 2—3 years after her first period, a girl's periods should be coming around once every 4—5 weeks. Yes, a girl can get pregnant as soon as her period starts. A girl can even get pregnant right before her very first period. This is because a girl's hormones might already be active. The hormones may have led to ovulation and the building of the uterine wall. If a girl has sex, she can get pregnant, even though she has never had a period.
Periods usually happen about once every 4—5 weeks. But some girls get their periods a little less or more often. You have many choices about how to deal with period blood. You may need to experiment a bit to find which works best for you. Some girls use only one method and others switch between different methods.
The lining of your uterus gets thicker as preparation for nurturing a fertilized egg. An egg is released and is ready to be fertilized and settle in the lining of your uterus. If the egg is not fertilized, your body no longer needs the thicker lining of the uterus, so it starts to break down and is eventually expelled, along with some blood, from your vagina. The way that women experience their periods varies widely. Your period is a natural occurrence.
If you experience inconsistencies such as a change in your menstrual regularity, frequency, duration, or volume, talk with your doctor or gynecologist. Many women believe they experience period syncing with other women they live with or are close to.
But is there scientific proof that this can happen…. The process of your uterus shedding its lining every month is called menstruation. Some discomfort during your period is common, but intense or…. A menstrual period is vaginal bleeding that occurs at the end of the monthly menstrual cycle. This is when the female body prepares itself for….
Having a headache during your period is pretty common, and is due to the hormonal fluctuations that occur at that time of your cycle. It may trigger a…. Like women, men have hormonal shifts and changes. The answer begins with pregnancy. During this process, the body's resources are cleverly used to shape a suitable environment for a fetus, creating an internal haven for a mother to nurture her growing child.
In this respect, pregnancy is awe-inspiring, but that's only half the story. The other half reveals that pregnancy places a mother and her child at odds. As for all living creatures, the human body evolved to promote the spread of its genes. For the mother, that means she should try to provide equally for all her offspring. But a mother and her fetus don't share exactly the same genes. The fetus inherits genes from its father, as well, and those genes can promote their own survival by extracting more than their fair share of resources from the mother.
This evolutionary conflict of interests places a woman and her unborn child in a biological tug-of-war that plays out inside the womb. One factor contributing to this internal tussle is the placenta, the fetal organ that connects to the mother's blood supply and nourishes the fetus while it grows. In most mammals, the placenta is confined behind a barrier of maternal cells.
This barrier lets the mother control the supply of nutrients to the fetus. But in humans and a few other species, the placenta actually penetrates right into the mother's circulatory system to directly access her blood stream.
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