Types of Combination Birth Control Pills

Differences Between Monophasic, Biphasic and Triphasic Pills

What Are Combination Birth Control Pills?

Combination birth control pills are oral contraceptives that combine ethinyl estradiol and progestin. Even though all combination birth control pills have estrogen, they can differ in the how much estrogen they contain. Combination birth control pills are also different from one another due to the amount and type of progestin that is in each pill brand. The combination of the amount of estrogen and the type and amount of progestin found in combination birth control pills can also cause different progestational, estrogenic, and androgenic effects.

Understanding the Types of Combination Birth Control Pills

Types of Birth Control Pills
Understanding Pill Types. Envision/Getty Images

Combination birth control pills are categorized as monophasic, biphasic or triphasic -- depending on whether the level of hormones stays the same during the first three weeks of your menstrual cycle or if it changes. Keep in mind that for 28-day pill packs, the pills for the fourth week are usually placebo pills (and do not have any hormones).

What is the Best Birth Control Pill Brand?

There is no "best" birth control pill brand. No birth control pill brand or pill type outranks all the others. Some pill brands may help to lower certain side effects. But all combination birth control pills are equally effective in preventing pregnancy -- as long as the pills are used consistently and correctly.

Multiphasic vs. Monophasic Birth Control Pills:

Multiphasic birth control pills were developed in the 1980s. Phasic birth control pills have differing amounts of hormones -- designed to be taken at specific times throughout the course of each pill pack. These pills were originally developed to help lessen the side effects of monophasic birth control pills. When compared to monophasic combination pills, some multiphasic birth control pills may lower the total hormone dosage you may receive in each pill pack. They are also designed to more naturally mimic your body's menstrual cycle.

1. Monophasic Birth Control Pills

Types of Birth Control Pills
Monophasic Birth Control Pills. Hidesy/Getty Images

Monophasic birth control pills have the same amount of estrogen and progestin in each active pill in the pill pack. The hormone levels in each pill stay consistent. So monophasic birth control pills may be less likely to cause side effects that could result from fluctuating hormones. Monophasic birth control pills are classified by their estrogen level:

  • Low dose pills have the least amount of estrogen - usually 20 mcg. But there is the birth control pill brand Lo Loestrin Fe. This is the only birth control pill that contains just 10 mcg of estrogen, so it is quietly becoming very popular.
  • Regular dose pills contain 30–35 mcg estrogen.
  • High-dose pills have about 50 mcg of estrogen.

Monophasic birth control pills work just as well as multiphasic pills. Low estrogen, monophasic pills may cause less bloating or breast tenderness -- but they may result in more spotting. Most women find that a monophasic birth control pill brand tends to be a good first choice.

2. Biphasic Birth Control Pills

Biphasic Birth Control Pills
Biphasic Birth Control Pills. Photo © Dawn Stacey

Biphasic birth control pills change the level of hormones one time during the pill pack. Biphasic birth control pills deliver the same amount of estrogen each day, but the level of progestin is increased about halfway through the pill cycle. During the first half of the cycle, the progestin/estrogen ratio is usually lower -- and during the second half of the cycle, the progestin/estrogen ratio tends to be higher. The first 7 to 10 days are one strength (and usually one color), and the next 11 to 14 pills are another strength (and another color). The last 7 days (if included) are placebo pills and do not hormones.

3. Triphasic Birth Control Pills

Types of Birth Control Pills
Triphasic Birth Control Pills. Steve Wisbauer/Getty Images

Triphasic birth control pills contain three different doses of hormones -- so the hormone combination changes approximately every 7 days throughout the pill pack. Depending on the pill brand, the amount of estrogen may change as well as the amount of progestin. In a single month's supply, triphasic birth control pills may have a slow increase in estrogen, and some pills may also increase the dose of progestin. In each pill pack: the first few pills are one strength (and one color). The next phase of pills are another strength (and another color). The final phase of pills also change strength and are a different color. The last 7 pills (if included) are placebo pills, so they do not hormones.


Christin-Maitre S. "History of oral contraceptive drugs and their use worldwide. Best practice & research." Clinical Endocrinology & Metabolism. 2013 Feb 28; 27(1):3-12. Accessed via private subscription/

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