Q. What are the stats regarding how effective condoms are, and how soon after sex would me and my girlfriend know if she was pregnant? We use condoms as our only form of birth control, but there was some fluid that looked like semen on the outside of the condom the last time we had sex.
A. According to the World Health Organization, if condoms are used consistently and exactly as directed, their effectiveness at preventing pregnancy is quite high, ranging somewhere around 97% - therefore a 3% failure rate. On the other hand, the pregnancy rate during “typical usage”, which basically accounts for incorrect and/or inconsistent use, is much higher, cited at between 10% to 14%. Since there's no such thing as absolute protection against pregnancy (except Abstinence), it's wise for you to expect a small margin of error and prepare for it accordingly. See our article on How Pregnancy Odds Work for more information.
Although it is difficult to know one's reaction to such a situation until it actually happens, discuss how each of you might feel if your partner did get pregnant, and assess the possible ways you would go about handling that outcome. Provided too much time hasn't elapsed since any slip, if you want to take extra measures to prevent conception from taking place, consider seeing a health care provider about emergency contraception. Also known as the Morning After Pill, this high dose of female hormones can be taken within a few days after intercourse - but the sooner it's taken, the more effective it is. However, this should only be considered an emergency option, as the major downsides are that it also isn't 100% effective, plus your girlfriend may have to undergo some uncomfortable side effects. The good news is that there are now progestin-only formulations available, which reportedly have less nausea, pain, and vomiting than combination hormone pills.
The question of “how soon after sex can we find out if she's pregnant” is a common one, and you can purchase an at-home pregnancy test to get an answer. At-home pregnancy tests can work well if they're used correctly, but the length of time a person has to wait before taking the test generally depends on the product you use. Realistically, you should prepare yourselves to wait for a couple of weeks, or until your girlfriend misses her period. Although some tests are sensitive enough to detect fertilization as soon as one week after intercourse, the closer you are to your expected day of menstruation, the better your chances are for an accurate result. In the event that the test does indicate pregnancy, contact your doctor to verify the results.
An excellent way to lessen your worry and make the stats work in your favor is to consider using a combination of Birth Control methods such as The Pill and Condoms. Another idea is to make an appointment at a sexual health clinic to get a primer on proper condom application. As has been explained, incorrect condom usage drops its effectiveness by approximately 10%, so it's worth having a pro review your technique. Remember, abstinence is the only way to guarantee a baby-free future, so if an Unplanned Pregnancy is something you don't want to contend with, there are plenty of non-vaginal ways to enjoy intimacy and sexual activity without the added worry; for plenty of ideas read up on Sexual Massage, Anal Sex, Foreplay, Oral Sex, etc.