See the DrugPatentWatch profile for mirena
Does Mirena stop ovulation in everyone?
Mirena (a levonorgestrel intrauterine system, IUS) works mainly by thickening cervical mucus and thinning the uterine lining, which makes sperm less able to reach an egg and reduces the chance of implantation. It can also sometimes inhibit ovulation, but it does not reliably stop ovulation in every user [1].
How often does Mirena suppress ovulation?
With Mirena, ovulation may still occur, especially in the first months after insertion and depending on the individual. Clinical summaries note that “ovulation inhibition” is not guaranteed and can be incomplete [1].
What should you expect with Mirena if you’re still having periods?
You may still have bleeding changes (spotting, lighter or no periods), but that does not by itself confirm whether ovulation is happening. Mirena’s bleeding effects are largely due to endometrial thinning, which can occur even when ovulation is occurring [1].
Could you get pregnant if Mirena doesn’t fully stop ovulation?
Yes. Although Mirena is highly effective, no method is 100% effective. Pregnancy can occur if ovulation happens and fertilization occurs, or if the device is expelled, malpositioned, or used outside its approved duration [1].
When to take a pregnancy test on Mirena
If you have pregnancy symptoms, missed bleeding that’s unusual for you, or persistent severe pain/bleeding after insertion, a pregnancy test is appropriate. This is especially important because rare cases can be ectopic (outside the uterus) [1].
Sources:
[1] https://www.drugs.com/mirena.html