OriginalDrugs

Birth Control Pills

Birth-control pills (oral contraceptives) are medications that prevent pregnancy. If birth control pills are taken correctly, they are 98-99% effective at preventing pregnancy. Delaying or missing even one pill significantly reduces their effectiveness.

Oral contraceptives are also used to treat acne and regulate menstrual periods.

Combination Pills

Combination birth control pills contain the hormones estrogen and progestin. Progestin is a synthetic form of the hormone progesterone. Most combination pills use the same form of estrogen (ethinyl estradiol), but different types of progestins.

Birth control pills differ in the way the estrogen and progestin are distributed over the course of the pack of pills.

There are three types of combination pills: monophasic, biphasic, and triphasic.

Multiphasic pills contain varied amounts of hormones which are designed to be taken at specific times throughout the course of each pill pack. These pills were developed in an attempt to decrease the side effects of monophasic pills. Multiphasic birth control pills tend to lower the total hormone dosage a woman receives throughout each pill pack.

Monophasic

One-phase pills contain the same amount of hormone for three weeks.

The packages usually contain 21 days of active tablets along with seven inert sugar pills. The oral contraceptive is taken for three weeks of the cycle, followed by seven days of sugar pills. This maintains a 28-day cycle. Women usually have their period within a couple of days of starting the sugar pills.

If a woman continued to take the active pills and not use the sugar pills, she apparently would not menstruate. Sometimes women use this technique to "skip" a period.

Note: The "skipping" technique can be realized only with monophasic birth control pills.

Seasonale is a monophasic birth-control pill packaged in a 91-day supply and is designed to prevent menstruation for the entire time period. Women taking Seasonale will have only four periods a year. Although many other monophasic birth control pills mey be used in this way, Seasonale is the only product approved by the FDA for use.

Examples of monophasic pills:

  • Alesse
  • Levlite
  • Levlen
  • Loestrin
  • Ortho-Cept
  • Ortho-Novum
  • Ortho-Cyclen
  • Ovcon
  • Yasmin

Biphasic

Biphasic pills have a fixed amount of estrogen, but there are two different strengths of progestogen. The first 7 to 10 days are one strength (and one color), and the next 11 to 14 pills are another strength (and another color). The last 7 tablets are placebo pills and contain no hormone.

Examples of biphasic pills:

  • Mircette
  • Necon
  • Ortho-Novum

Triphasic

Depending on the brand, the amount of estrogen may change as well as the amount of progestogen. There are actually three different doses in the dispenser. The hormone combination (and the color) changes approximately every 7 days throughout the pill package.

Examples of triphasic pills:

Minipill (Progestin-Only)

Minipills or progestin-only pills (POP) contain only one hormone, progestin. Each tablet in the pack is the same. Minipills are slightly less effective than combined birth control pills. Even missing one pill can greatly reduce effectiveness.

They are appropriate for women who have conditions that prevent them from taking estrogen.

Examples of minipills pills:

  • Micronor
  • Nor-QD
  • Ovrette

Emergency contraceptive pills

Emergency contraceptive pills, also called "the morning after pill", are used to prevent pregnancy after unprotected sex. Emergency contraception is most effective the sooner it is taken after sex.

In the United States, there is only one FDA-approved ECP pill called Plan B. However, number of brands of regular birth control pills also can be used as ECPs.

In general, progestin-only emergency contraceptive pills are more effective than combined emergency contraceptive pills. Labeling for Plan B and other emergency contraceptive pills that contain only the hormone progestin states that the treatment reduces the risk of pregnancy by 89%.

Other medications for woman's health

Last updated: January, 2010