Birth control pills, or oral contraceptives, are prescription-based synthetic hormones. Most pills contain a combination of estrogen and progestin. Some also contain seven days of inactive spacer tablets. Oral contraceptives work by preventing ovulation, fertilization or implantation of an egg. The hormones in the pill also prevent sperm from entering the uterus by thickening cervical mucus. The pills can be triphasic, biphasic or monophasic, which varies the dosage of hormones taken throughout the month.
Combination Pills
Combination pills can be either 21-day or 28-day pills and contain synthetic versions of both progesterone and estrogen. These are the most commonly prescribed type of oral contraceptives. In addition to the primary function of birth control pills, combination pills can also help to treat and prevent acne, ovarian cysts, endometriosis, ectopic pregnancies and iron-deficiency anemia. Combination pills can also control the timing and frequency of your periods. Both 21-day and 28-day pack pills have 21 active tablets that contain the synthetic hormones. 28-day birth control pills contain 7 inactive reminder pills to be taken during the last week of the pack. Taking these inactive pills will allow you to have a period. Common brand names of combination pills include Alesse®, Aviane®, Brevicon®, Loestrin®, Mircette®, Ortho Tri-Cyclen®, Ovcon®, Ortho-Novum®, Yasmin® and Yaz®.
Progestin-only Pills
Progestin is the name given to synthetic progesterone. Progestin-only pills, also referred to as "mini-pills," come only in 28-day packs. Progestin-only pills typically have fewer side effects and are safer for women who are breast-feeding, overweight, smokers or have a history of blood clots. Mini-pills may cause light bleeding in between periods and may also cause an increase in appetite. It is very important to take this type of birth control pills at the same time every day. If you miss a dose by more than three hours, take it as soon as you remember and use another form of birth control for at least 48 hours following your missed dosed. If you miss a dose by an entire day, you must use another form of birth control for the rest of that month. The most popular brand names of progestin-only pills are Cerazette®, Ovrette®, Ortho-Micronor®, Errin®, Camilla® and Jolivette®.
91-day Pills
The 91-day pills are extended-cycle birth control. These are combination pills that prevent ovulation and delay your period. Extended-cycle birth control pills generally contain 84 active pills and 7 reminder pills. The 7 reminder pills allow you to have a period during the last week of the three-month dose. You can also do extended cycling with 21-day and 28-day pack pills, by just continuing to take active pills during the last week of the pack. Talk with your physician before changing your dosage frequency. Common brand names of extended-cycle oral contraceptives are Jolessa®, Seasonale®, Seasonique® and Quasense®.
