Comparing Birth Control Pill Types: Combination, Minipills, and More

Birth Control Pill Type: Emergency Contraceptive Pills

The emergency contraceptive pill is meant to be used to prevent a pregnancy after unprotected sex. The only FDA-approved emergency contraceptive available in the U.S. is Plan B. Plan B is available over-the-counter to women 18 and older.

The emergency contraceptive pill contains a form of progestin called levonorgestrel. It works by preventing ovulation. But it won't stop the fetus from developing if you're already pregnant. It's taken in two doses. You take the first dose as soon as possible after having unprotected sex. The second dose is taken either right afterward or 12 hours later. Plan B is effective for up to five days after having unprotected sex.

If you don't have Plan B on hand and you've had unprotected sex, it's also possible to take several of your regular birth control pills as a form of emergency contraception. This is known as the Yuzpe regimen. But ask your doctor about the exact dosing.

What are the pros of emergency contraceptive pills?

There are two main benefits associated with emergency contraceptive pills:

• They decrease the risk of an unintended pregnancy by about 87%.
• There is no risk of harm to the fetus if you do get pregnant.

What are the cons of emergency contraceptive pills?

There are several disadvantages to emergency contraceptive pills:

• Women under 18 cannot get these pills without a doctor's prescription.
• The pills must be taken within 120 hours -- five days -- of unprotected sex.
• Side effects include nausea, vomiting, dizziness, fatigue, breast tenderness, and headache.

Choosing a Birth Control Pill

Unless you are breastfeeding or have a medical condition such as a history of blood clots, your doctor will most likely start you on a combination pill. If you want to reduce the number of periods you get a year, the doctor might prescribe an extended-cycle pill.

It's important to discuss all of your birth control options with your ob-gyn before making a decision. "Women thinking about birth control pills need to ask themselves if they are going to be good pill takers and take the pills at the same time every day," says Hillard. If not, you might want to consider another form of contraception. Also, talk to your doctor about possible side effects and interactions that birth control pills can have with certain medications.