Yaz is not a progestin-only pill. It is a combination birth control pill that contains two hormones: a synthetic progestin called drospirenone (3 mg) and a synthetic estrogen called ethinyl estradiol (0.02 mg). Every active tablet in a Yaz pack delivers both hormones together.
What Yaz Actually Contains
Each Yaz pack follows a 24/4 schedule: 24 active tablets with both drospirenone and ethinyl estradiol, followed by 4 inactive (placebo) tablets. This differs from the more traditional 21/7 layout used in many older combination pills. The three extra days of active hormones help keep hormone levels steadier throughout the cycle, which can reduce breakthrough bleeding and hormonal fluctuations during the placebo days.
The estrogen dose in Yaz (0.02 mg of ethinyl estradiol) is on the lower end compared to other combination pills, which is why Yaz is sometimes called a “low-dose” oral contraceptive. But low-dose does not mean progestin-only. The estrogen component is still present and plays an active role in how the pill works.
How Combination Pills Differ From Progestin-Only Pills
The distinction matters for more than just labeling. Combination pills like Yaz prevent pregnancy through multiple mechanisms: they stop the ovaries from releasing an egg, thicken cervical mucus so sperm can’t easily pass through, slow egg transport through the fallopian tubes, and thin the uterine lining. Progestin-only pills rely primarily on thickening cervical mucus and thinning the uterine lining, and only some formulations consistently suppress ovulation.
The timing rules are also different. With progestin-only pills, all the tablets in a pack are active (no placebos), and the pill needs to be taken at the same time every day. If you take a traditional progestin-only pill more than three hours late, you need backup contraception for at least two days. Combination pills like Yaz have a wider window for timing, though consistency still improves effectiveness.
Progestin-only pills are typically recommended for people who can’t take estrogen, such as those with a history of blood clots, certain types of migraines with aura, or those who are breastfeeding. If you’ve been told to avoid estrogen and are considering Yaz, it would not be an appropriate choice.
What Makes Drospirenone Unique
The progestin in Yaz, drospirenone, is not derived from testosterone like many older progestins. It has anti-androgenic properties, which is part of why Yaz is FDA-approved to treat moderate acne in women 14 and older (as long as they also want contraception). It’s also approved for treating symptoms of premenstrual dysphoric disorder (PMDD), a severe form of PMS that causes significant mood and physical symptoms before menstruation.
Drospirenone also has mild potassium-sparing diuretic effects similar to the medication spironolactone. This initially raised concerns about dangerously high potassium levels, but clinical data has been reassuring. Studies found no increased rate of elevated potassium in women using drospirenone-containing pills compared to other oral contraceptives, even among women with type 2 diabetes or those taking blood pressure medications that also affect potassium. That said, your prescriber may still consider this property if you take other medications that raise potassium levels.
Pills That Are Progestin-Only
If you’re specifically looking for a progestin-only option, those are sold under different brand names entirely. Traditional progestin-only pills (sometimes called the “minipill”) include brands like Camila, Errin, and Heather, which contain norethindrone. A newer progestin-only pill containing drospirenone (the same progestin found in Yaz, but without any estrogen) is also available under the brand name Slynd. Slynd has a more forgiving missed-pill window than older minipills, making it a closer experience to taking a combination pill.
The overlap of drospirenone in both Yaz and Slynd may be one reason for confusion. Both use the same progestin, but Yaz pairs it with estrogen while Slynd does not. The presence or absence of estrogen changes eligibility, side effect profiles, and how strictly you need to watch the clock each day.