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Ask Dr. K

When is the safest time to have sex -- when a girl is starting her period, ending her period, or what?

If you use a condom or another form of contraception, you don't have to worry about which time of the month you might be fertile (able to get pregnant). But just so you know, the fertile period in a woman's menstrual cycle usually lasts for three days, but can be up to 10 days due to the life of sperm. The fertile time begins about 14 days before a girl has her period. Trying to time your sexual activity without using any other contraception is called the rhythm method and has a high failure rate (10-20%). Condoms and birth control pills are much more effective, and condoms also protect you against HIV and STD transmission.

To your health,
Dr. K

Last modified on Tuesday, June 03, 2008.
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