unintended pregnancies. But what happens when things don't go quite as planned?

Thanks to modern science a second chance is possible. So how does emergency

contraception or "plan-b" work? And what exactly is happening inside the female

body? During the female menstrual cycle many hormones are released

beginning a chain reaction. The pituitary gland in the brain releases FSH

which stimulates the growth of follicles and a premature egg in the ovaries.

These follicles then release estrogen

which helps prepare the uterus lining and triggers the brain to release leutinizing

hormone or LH. LH then triggers ovulation in which the egg is

released into the fallopian tubes where it will spend around twelve to twenty-four

hours waiting to be fertilized. If the egg isn't fertilized in this time it

begins to dissolve and is shed away with the uterine lining during menstruation.

Though this window of opportunity is brief it's increased by the fact that sperm

can live for up to five days.

So the keen sperm from days ago show up early to the show anxiously awaiting

ovulation.

Birth control pills taken on a regular basis modify these hormone levels. By

increasing progestin levels the body thinks it's already released an egg or

already pregnant.

It effectively decreases FSH and LH and the cycle halts. But in the case

of emergency contraception which is only taken if regular contraception methods

fail,

a few different mechanisms take place. The most important thing to understand

is that fertilization doesn't happen immediately or even within hours after

intercourse. Instead the sperm must undergo a few biological changes in the

fallopian tube first which takes time. This is why emergency contraception is

still possible the morning after.

It can actually work up to five days after intercourse. If taken during the

first half of the menstrual cycle, emergency contraception works

specifically to prevent ovulation.

This way the egg is not released even though it may be ready and the available

sperm cannot fertilize it.

In cases where it's too late to inhibit ovulation

emergency contraception is thought to also thicken cervical mucus trapping sperm.

As well, it may directly inhibit fertilization between sperm and egg.

Clinical studies show that emergency contraception prevents pregnancy

before fertilization. No studies have shown an effect from emergency

contraception if fertilization has already occurred. It does not stop

implantation from happening nor does it have any effect after implantation has

occurred.

In this way, its unable to cause an abortion.

And while there are some minor side effects to these drugs, such as nausea and headaches,

scientific studies have demonstrated its safety in women of all ages and found

that the benefits far outweigh any risks. Got of burning question you want answered?

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