Levonorgestrel vs Other Progestins: Differences, Uses, and What Matters Most

When it comes to hormonal birth control and emergency contraception, levonorgestrel, a synthetic progestin used in pills like Plan B and many IUDs. Also known as LNG, it's one of the most widely used progestins in the world. But it’s not the only one. Other progestins like norethindrone, desogestrel, and drospirenone are in different pills, patches, and implants. So why does levonorgestrel keep showing up in emergency kits and IUDs? And how does it really compare to the others?

Levonorgestrel works mainly by stopping ovulation and thickening cervical mucus to block sperm. It’s fast-acting and effective in emergency contraception when taken within 72 hours after unprotected sex. But other progestins? They’re often designed for daily use. Norethindrone, for example, is common in regular birth control pills and can be used for period control or endometriosis. Drospirenone, found in pills like Yaz, also acts like a diuretic and helps with acne and PMS. Each one has a slightly different chemical shape, which changes how your body reacts. That’s why side effects vary—some people get bloating with one, mood swings with another, and almost nothing with levonorgestrel.

One big difference is potency. Levonorgestrel is strong in small doses, which is why it’s the go-to for emergency pills—just one or two tablets do the job. Other progestins need higher doses or longer exposure to work the same way. That’s also why the levonorgestrel IUD (like Mirena or Kyleena) can last for years: it releases a steady, low amount right where it’s needed. Compare that to a progestin-only pill that you have to take at the same time every day—miss one, and effectiveness drops. The delivery method matters as much as the chemical itself.

It’s not just about effectiveness. Cost, availability, and how your body handles it matter too. Levonorgestrel is cheap, widely available over the counter in many places, and has decades of safety data. Newer progestins like desogestrel or etonogestrel (in Nexplanon) might offer fewer side effects for some, but they’re often more expensive and require a prescription. And while levonorgestrel doesn’t affect blood pressure much, drospirenone can raise potassium levels—something you need to watch if you have kidney issues.

So when you’re choosing between options, it’s not just about which progestin is "better." It’s about what fits your life. Need a backup plan after unprotected sex? Levonorgestrel is your best bet. Looking for long-term, low-maintenance birth control? A levonorgestrel IUD might be ideal. Want to manage acne and mood swings? Another progestin could be the right match. There’s no universal winner—just the right tool for your body and needs.

Below, you’ll find real comparisons from people who’ve tried different progestins—what worked, what didn’t, and what surprised them. No fluff. Just clear, practical insights to help you make sense of your options.