You said you absolutely, positively, can take NO risks in becoming pregnant (or in getting a partner pregnant), and/or know that you do not want to become pregnant right now, or possibly ever.
There are many methods of highly effective birth control, but none of them are 100% effective, even with perfect use: there will always be some risk, from a very slight one to a more moderate risk of pregnancy if you are having genital intercourse and are using one of those methods.
If you're someone who does not want to take ANY risk, at all, of a pregnancy, the only way to completely avoid that risk is to either avoid any sexual activity where someone has a penis and the other person has a vulva, or refrain from sexual activities which pose a risk of pregnancy (vaginal intercourse, anal intercourse direct genital-to-genital rubbing, or any genital exposure to semen).
Some sexual activities which do not pose any risk of pregnancy include:
Just remember that same-sex sexual activity and some of the sexual activities listed above can still pose risks of sexually transmitted infections.
If this is the route you choose to go, you'll want to do some things to support that and assure it is used effectively. For instance, you'll want to be sure you can be strongly assertive when it comes to setting and insisting on the boundary around sex that poses pregnancy risks with any partner you get involved with. You'll want to be sure a partner is just as on-board with this approach as you are. You'll also want to make sure that, in the case you do find yourself changing your mind in the heat of the moment, you've got a reliable method of contraception you can and know how to use, just like someone who chose to have intercourse and to use condoms, but knew they may not consistently use them, should have a backup method if they want to avoid unwanted pregnancy.
For those who wish to be sexually active, including activities which pose a risk of pregnancy and want NO risk of pregnancy, male or female sterilization (vasectomy or tubal ligation) are also options. However, as we mentioned on the previous page, these options are surgical and are rarely okayed for younger people by doctors since for most people, those are permanent methods of birth control which either cannot be reversed, or are costly to reverse, and/or are not always successful in reversal. However, if this is something you are interested in, the person to speak to about it is your doctor or your sexual healthcare provider.
Bear in mind that consistently combining two reliable methods of birth control -- like a hormonal method and condoms, or like condoms and a cervical barrier -- does not give you 100% protection against pregnancy, but it's pretty darn close. If you already have taken a risk you're not comfortable with, or know or suspect a birth control method has failed and wish to prevent pregnancy, we suggest you consider emergency contraception.
If you've changed your mind and know that you still want to and will engage in sexual activities which pose pregnancy risks, and have become willing to take some risk in becoming pregnant, or just want to see what some birth control options are, go back a question and start over.
Don't forget: Statistically, sexually active young adults are as, if not more, likely to acquire a sexually transmitted infection (STI) as you are to become pregnant. Although 15-24-year-olds represent only one-quarter of the sexually active population, they account for nearly half of all new STIs each year, and of the 18.9 million new cases of STIs each year, 9.1 million (48%) occur among 15-24-year-olds (AGI). Often people have some funny ideas about who is most likely to get an STI, but the fact of the matter is that younger people -- of any sexual orientation, any economic class, any kind of relationship -- have been the highest risk group for some time now.
Condoms are the only method of birth control which also provide protection against STIs. It's pretty typical for younger people to ditch condoms if they have another method of birth control, so just remember that STIs are still a risk if you're using another method. You can read all about safer sex here -- Safe, Sound & Sexy: A Safer Sex How-To -- but the rule of thumb most medical experts and prevention organizations suggest, which we also encourage at Scarleteen is six months of safer sex, six months of sexual monogamy, and then TWO full STI screenings for each partner -- once at the start of that six months, once at the end -- before ditching latex barriers.