Seasonique is an extended-cycle combination birth control pill which prevents pregnancy and suppresses menstruation for 91-day cycles. Taking Seasonique with perfect use (not missing any pills) will typically result in the female experiencing only four periods a year. The gap between periods is completely safe and causes no health problems. Another form of birth control pill, known as the continuous-cycle birth control pill, is able to prevent menstruation for an entire year, or even longer, without causing any long-term reproductive difficulties. While Seasonique and other forms of hormonal birth control pills are able to prevent pregnancy, they offer absolutely no protection against Sexually Transmitted Infections. Barrier methods of contraception, like condoms, should be used in conjunction with hormonal birth control pills to reduce the risk of STIs and unwanted pregnancy.

How Seasonique Works

Similiar to traditional combination pills, Seasonique uses the hormones estrogen and progestin to inhibit ovulation, meaning no egg is released by the ovaries for sperm to fertilize. The hormones also thicken the cervical mucus, making it harder for sperm to get through the cervix into the uterus. Additionally, the hormones thin the lining of the uterine lining, making it more difficult for a fertilized egg to implant and develop into a fetus. Seasonique differs from other  combination pills because it suppresses menstruation for 91 days, instead of the traditional 28-day cycle. Seasonique, like other extended-cycle birth control pills, achieves this by maintaining a high concentration of estrogen and progestin in the body, mimicking pregnancy. This causes the menstrual cycle to remain dormant, as it does during a real pregnancy; thus halting menstruation. The last seven pills in each pack contain lower levels of estrogen and progestin to initiate menstruation and restart the menstrual cycle.

How to Use Seasonique

Each pack of Seasonique comes with 91 pills meant to be taken once each day. As with all forms of hormonal birth control, Seasonique is most effective when taken at the same time every day. For 84 days (as long as all 84 pills are taken appropriately) the pills will simultaneously prevent pregnancy and inhibit menstruation. The last 7 pills contain lower hormone levels than the rest of the pack which will drop the levels of estrogen and progestin in the body. This hormonal change initiates period-like symptoms such as bleeding and spotting. It is important to continue taking the pills during this period as they are not placebos and are necessary to maintain stabilized hormone levels during the menstrual week. The final seven pills continue to work as a contraceptive and a new Seasonique pack should be started the day after previous pack is finished.

A pack of turquoise and yellow pills. The pill case is labeled "seasonique."

Seasonique can also be used as an emergency contraceptive pill (ECP).1 ECPs are most effective at preventing ovulation, fertilization, and pregnancy within 72 hours after the unprotected sexual encounter; however, ECPs may be effective up to five days after the encounter.2 If Seasonique is being used as an ECP, the user should take four pills at once and then an additional four pills twelve hours later. Using combination birth control pills like (Seasonique) as an ECP is discouraged as progestin only pills (like Plan-B or the morning after pill) are usually safer and more reliable alternatives.1

Missed Pills

If one pill is missed, the user should take the missed pill as soon as possible. Then the next pill should be taken at the usual time. If a user misses two pills, they should take both pills as soon as possible, and then TWO additional pills at the next usual time. There is an increased risk of pregnancy for seven days after missing two pills, so another form of birth control (such as a condom) is recommended. If the user misses three or more pills, they should leave them in the packet (and not take them), then continue taking one pill each day at the regular time. In this case, another method of birth control IS REQUIRED for seven days as there is a very high risk of pregnancy without any backup protection. If the user misses one of the last seven pills, they should skip it and continue taking the other low dosage pills normally. This should not increase the risk of pregnancy.


Seasonique has a perfect use failure rate of 0.3% and typical failure rate of 5%. This means that about three in 1000 users become pregnant every year with perfect use, and that around five in 100 users become pregnant with typical use.3


Seasonique costs about one dollar per pill, or around thirty dollars a month, which is similar in price to other forms of birth control pills. This cost can be greatly decreased depending on a person’s insurance, or free clinics in their area.

Side Effects

If you begin to experience any serious side effects, contact a medical professional immediately. A rare allergic reaction to Seasonique may include constricted breathing, yellowing of the skin, hives, and swelling of the face or any organs located on the face. Serious reactions to the pill should be reported to a doctor, and the pill should be discontinued immediately. Other serious side effects include depression, difficulty sleeping, numbness, severe headaches, difficulty seeing or speaking, chest pain, heavy coughing, severe nausea, swelling of the limbs, and breast lumps.

Less serious side effects from Seasonique include a change in menstrual cycle or discharge, spotting in between periods, vaginal itching, weight gain or loss, cramps, bloating, nausea, and tenderness of the breasts. Nausea can occur when taking Seasonique, but often decreases over time. Each individual reacts differently to different forms of birth control. If your body does not respond well to Seasonique, consult with your doctor about alternative contraceptives.

If you are taking any other medication, inform your doctor before beginning Seasonique.

Hormonal contraceptives have notable health benefits as they decrease the risk of ovarian cysts, benign breast tumors, ectopic pregnancies, anemia, pelvic inflammatory disease, and dysmenorrhea.3

Concluding Remarks

Seasonique is an extended-cycle birth control pill that protects against pregnancy while also reducing the number of periods the user experiences. This gap between periods has not been found to cause any reproductive or general health problems. Seasonique and has led to the creation of continuous-cycle birth control pills, like Amethyst, which continuously suppress the menstrual cycle for even longer periods of time. Extended-cycle and continuous-cycle birth control pills are just as effective, healthy, and reversible as any other kind of hormonal birth control.


  1. “Emergency Contraception: Seasonique.” Princeton University, The Trustees of Princeton University, 14 Aug. 2017.
  2. “EC Methods.” Association of Reproductive Health Professionals, Mar. 2011.
  3. Burness, C B. “Extended-Cycle Levonorgestrel/Ethinylestradiol and Low-Dose Ethinylestradiol (Seasonique(®)): A Review of Its Use as an Oral Contraceptive.” Pub Med, U.S. National Library of Medicine, June 2015.

Last Updated: 10 December 2017.