Answer:
There are various rumors about ways to do this, but the truth is none of them are safe and few of them even work.
If you are thinking of doing this for someone else, it is illegal and you can be sent to prison for practicing medicine without a license and/or for assault if you disfigure or injure the pregnant woman or the unborn child. If the results are fatal, as they most often are when done by people without advanced medical training as a physician, you could be found guilty of manslaughter or probably murder.
If you are considering it as something to do to yourself, it again is most often life threatening. If it doesn't cause your death, you'll end up getting professional medical care due to hemorrhage or infections anyway, so you might as well start with professional care. If you wouldn't attempt eye surgery on yourself, you shouldn't even consider causing a miscarriage. There are many new arteries and blood vessels formed with pregnancy and before you could do anything to stop the bleeding, you would likely bleed to death. This is true whether you attempt the miscarriage using surgical means or drugs to induce the abortion.
The first step is to prevent unwanted pregnancy. Use a condom or other form of birth control before sex. Or there are Emergency Contraceptives both mechanical and in pill form (often referred to as "morning after" pills or Emergency Contraceptive Pills) that you can take up to three days after unprotected sex as a safe option to avoid pregnancy in the first place. Although, according to the FDA, they are safe when used as indicated, these pills are considered only 75% effective. They are available Over The Counter in the US and are called Plan B.
If prevention is not done in time and you are faced with an unwanted pregnancy, the best thing to do is to find a clinic, doctor, or Planned Parenthood location where you can be seen by a professional and find out what options are available to you now and for you to use to prevent future unwanted pregnancies.
They will give you medically correct and unbiased information on ALL options available to you (i.e., prenatal care and having and raising the child, adoption options and processes, or ending the pregnancy if that is an option in your case). They can help you as well with your current medical needs while you make the best decision for yourself.
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