服用避孕药。 长期服用的口服避孕药。 其他女用避孕用品。 非激素药物。

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Female contraceptives can shorten the length of a period over time.  Some can shorten the length of bleeding and result in a lighter flow.  Others can reduce the number of periods you have in a year.  Oral contraceptives (OC, The Pill).  When you take oral contraceptives, you typically take one active pill a day for 21 days.  Active pills are made up of the female hormone estrogen or a combination of estrogen and progesterone.  Then you take a placebo pill for 7 days.  There are no hormones in the placebo pill, and that's what allows you to get your period during this time.  The most common way to reduce or suppress menstruation is to skip the placebo week and immediately start a new pack of pills.  Without the placebo week, your body won't have the opportunity to start a period. This works best if you're on an oral contraceptive that combines estrogen and progesterone and offers the same dose of hormones in each active pill each day.  This is called a monophasic combined oral contraceptive (COC). There are a number of monophasic combined oral contraceptives on the market including Ovral, Ovcon, Ogestrel, Nordette, Levora, Levlite, Apri, Alesse, Brevicon, Levlen, Loestrin, Norinyl, Ortho-Cept, Ortho-Cyclen, and Ortho-Novum. Oral contraceptives are available by prescription only, so you must see your doctor.  Let them know how you plan to use the Pill so they can choose the right one for you. Oral contraceptives may cause some minor side effects such as: headaches, nausea, breast tenderness, slight weight gain, and slight spotting of blood between periods.  Their use has been linked to blood clots, heart attack and stroke, especially in women who smoke, are overweight, have high blood pressure, or are over the age of 35.  OC's do offer some health benefits:  women who use them have a lower risk of developing endometrial cancer and ovarian cancer. Some oral contraceptives are intended to reduce the number of periods a woman has in a year, typically to four.  These pills work by providing an 84-day series of...