Combined Oral Contraceptive Patient Fact Sheet

What is a combined oral contraceptive?
Combined oral contraceptive (COC), also known as the birth control pill or just “the pill” is a medication taken daily to prevent pregnancy. Some women take the pill for other reasons than preventing pregnancy. COCs contain two hormones, estrogen and progestin. These pills are taken every day and prevent pregnancy by keeping the ovaries from releasing eggs. The pill also works by causing the cervical mucus to thicken, which blocks sperm from meeting with and fertilizing an egg.

How do I use it?
Combined pills are typically packaged as 21 “active” pills that contain hormones. One pill is taken daily for 3 weeks, followed by 1 week off. Others are packaged as 28 pills that include 21 “active” pills taken daily, followed by 1 week of “inactive” reminder pills that don’t contain hormones (Loestrin, Nortrel, Ortho Tri-Cyclen, Tri-Sprintec). With either the 21- or 28-day pills, protection against pregnancy continues during the week where no active pills are taken.

Some women use combined pills to limit the number of periods they have, or even to prevent them altogether. Extended cycle use involves taking 12 weeks of active pills followed by one week of inactive pills. Women on an extended cycle have 3 or 4 periods a year. The active ingredients in extended cycle contraceptives are levonorgestrel with ethinyl estradiol (Jolessa, Seasonique, Camrese). Continuous use of pills is where a woman takes an active pill daily so she will not have any periods.

What are the advantages?

  • Safe and effective in preventing pregnancy
  • Do not have to think about birth control when you want to have sex
  • Additional benefits such as fewer menstrual cramps, less acne, and stronger bones
  • May also reduce the risk of some cancers that affect reproductive organs

What are the disadvantages?

  • The pill does not protect against sexually transmitted infections (STIs)
  • You must take your pills every day
  • Certain antibiotics and supplements may make birth control pills less effective
  • If you stop the pill, it may take a month or two before normal periods return
  • Combined pills may cause dizziness, nausea, mood swings, and weight gain (these side effects often go away in a few weeks or months). Discuss your medical history with your health care provider before using any birth control pill, and let them know if you develop any side effects.
  • Rarely, use of the combined pill increases the risk of blood clots, heart attack, and stroke.