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What do girls get pregnant from?

There are a lot of myths and misconceptions out there about what causes pregnancy. So, what does cause pregnancy?

Pregnancy occurs when a sperm fertilizes an egg. The egg is released from the ovary during ovulation. The sperm swims up through the vagina and into the uterus, where the egg is waiting. If the sperm fertilizes the egg, it implants in the lining of the uterus and pregnancy begins.

So, pregnancy requires three things: an egg, a sperm, and fertilization. Let’s take a closer look at each of these.

The egg: an overview Eggs are produced in the ovaries. At birth, girls have all the eggs they will ever have — about 2 million. By puberty, that number has decreased to about 300,000. Of those eggs, only 300 to 400 will be released during a woman’s reproductive years (the time between her first period and menopause). During each menstrual cycle, one egg is usually released. The release of an egg is called ovulation. Once an egg is released, it can be fertilized by a sperm for 12 to 24 hours before it dissolves. If it isn’t fertilized within that time frame, it will dissolve and you will get your period (the shedding of the uterine lining). Eggs are really small — too small to be seen with the naked eye — about the size of this o (.). So how does an egg get from the ovary to the fallopian tube? The process starts with something called follicular development — when several follicles (fluid-filled sacs that each contain an immature egg) start growing in your ovary in response to hormones produced by your pituitary gland (a pea-sized gland at the base of your brain). One follicle will continue to grow faster than all the others and will become dominant. As this happens, its associated egg also starts to mature more quickly than all the others. This dominant follicle continues to grow until it’s about 18 to 20 millimeters in diameter (about as big around as a pencil eraser). At this point in your cycle (about day 14), another hormone surge from your pituitary gland triggers ovulation — meaning that dominant follicle ruptures and releases its matured egg into your fallopian tube where it begins its journey toward your uterus... Hopefully meeting up with a sperm along they way! If you want to get pregnant, timing is everything: sperm can live inside your body for up to five days after sex... But an unfertilized egg only lasts 12 to 24 hours after being released from its follicle during ovulation! So if you have sex before or after ovulation (meaning that there are no eggs available for fertilization), you won’t get pregnant because there’s nothing for those little swimmers to do but wait around until their welcome has worn out! Now let’s talk about those little swimmers.. The sperm: an overview each ejaculation (release of seminal fluid during sexual intercourse) contains between 20 million and 150 million sperm! And each one of those tiny cells has just one job: travel up through a woman’s vagina into her uterus so that it can fertilize heregg. That sounds like a pretty tall order considering they are just 0.005 inches long (.13 millimeters), have no legs or wings (they travel by wiggling their tails), live for only 48–72 hours once inside her body and have to swim upstream through cervical mucus before they even reach her fallopian tubes where most fertilization occurs! Talk about survival of fittest!! Once inside her vagina, most sperm die within minutes... But some make their way through her cervix into her uterus within 20 minutes or less! How do they know which way is up?! Well lucky for them cervical mucus actually provides clues! When she isn’t fertile (during most of her cycle), cervical mucus acts as barrier — thickening so that sperm can’t penetrate it easily and pointing them in wrong direction with its acidic ph level.. But when she is fertile (near ovulation), cervical mucus thins out and neutralizes its ph level so that swimming upstream becomes much easier for those little guys! Once inside her uterus, gravity pulls them toward her fallopian tubes where most fertilization occurs.. But if she had sex close enough to ovulation time or if she orgasms, contractions help push them along even faster!! And remember how we said earlier that each ejaculate contains between 20 million and 150 million sperm? Well guess what?! Only about 200 of those sperm make it to her fallopian tubes!!! Talk about survival of fittest again!!! So now we know what causes pregnancy — but there are still some things we don’t know like why some women seem more fertile than others or why some couples who have been trying unsuccessfullyto conceive for months or even years suddenly find themselves expecting!. Stay tuned for our next article on fertility which will help answer some of those questions!!