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词条 Extended cycle combined hormonal contraceptive
释义

  1. History

  2. Usage

  3. Clinical indications

  4. Side effects

     Ad campaign 

  5. Brands

  6. References

  7. Further reading

  8. External links

{{Infobox Birth control
|name = Extended cycle combined hormonal contraceptives
|image =
|width =
|caption =
|bc_type = Hormonal
|date_first_use = 1993 (first randomized study)[1]
|rate_type =
|perfect_failure% =
|typical_failure% = 0.9
|duration_effect = varies
|reversibility = Yes
|user_reminders = varies
|clinic_interval =
|STD_protection_YesNo = No
|periods = Eliminates or reduces frequency
|benefits = Reduce menstruation related symptoms, reduce risk of anemia
|weight_gain_loss =
|risks =
|medical_notes =
}}Extended or continuous cycle combined oral contraceptive pills are a packaging of combined oral contraceptive pills (COCPs) that reduce or eliminate the withdrawal bleeding that would occur once every 28 days in traditionally packaged COCPs. It works by reducing the frequency of the pill-free or placebo days. Extended cycle use of COCPs may also be called menstrual suppression.[2]

Other combined hormonal contraceptives (those containing both an estrogen and a progestin) may also be used in an extended or continuous cycle. For example, the NuvaRing vaginal ring[3] and the contraceptive patch[4] have been studied for extended cycle use, and the monthly combined injectable contraceptive may similarly eliminate bleeding.[5]

History

{{Expand section|date=June 2007}}

Before the advent of modern contraceptives, reproductive age women spent most of their time either pregnant or nursing. In modern western society women typically have about 450 periods during their lives, as compared to about 160 formerly.[6]

Although it was evident that the pill could be used to suppress menstruation for arbitrary lengths of time, the original regimen was designed to produce withdrawal bleeding every four weeks to mimic the menstrual cycle.[7]

Usage

When a woman takes COCP, the hormones in the pills prevent both ovulation and shedding of the endometrium (menstruation). Traditionally, COCPs are packaged with 21 active (hormone-containing) pills and 7 placebo pills. During the week of placebo pills, withdrawal bleeding occurs and simulates an average 28-day menstrual cycle. The placebo pills are not required for pregnancy protection, and with any monophasic COCP the placebo pills may be discarded, and the next pack of active pills may be started to prevent the withdrawal bleeding.[13] In a 12-month study of a continuous COCP regimen, 59% of women experienced no bleeding in months six through twelve and 79% of women experienced no bleeding in month twelve.[14] Extended or continuous use of COCPs or other combined hormonal contraceptives carries the same risk of side effects and medical risks as traditional COCP use.

Ad campaign

One of the early extended-cycle COCPs, Seasonale, was marketed with the campaign, "Fewer periods. More possibilities." In December 2004, Barr Pharmaceuticals was warned by the FDA concerning these television advertisements. As the warning stated, "By omitting and minimizing the risks associated with Seasonale, the TV ad misleadingly suggests that Seasonale is safer than has been demonstrated by substantial evidence or substantial clinical experience."