Mirena is a T-shaped device which releases hormones through a copper wire; the hormones and the wire do things to reduce the chances a woman has of becoming pregnant. With an IUD in place, the uterine lining is unable to thicken, makes cervical mucus sticky and produces chemicals which will destroy sperm. An IUD makes it almost impossible for sperm to reach the egg and if it does, it will not likely implant in the uterus. The chances of getting pregnant with an IUD (Mirena) are very slim, however there have been pregnancies reported for some women. Failure rates for IUD's are approximately 1 in every 1000 women and after having it in place for about 7 years; the rates go up to 7% per 1000 females. Women with a copper IUD have a slightly higher rate of pregnancy 6 in 1000 women, and after 10 years the rates rise to 20-30 out of 1000 women.
The two main reasons of women getting pregnant with an IUD (Mirena) are because the device becomes dislodged or is expelled. To check the device for proper placement, a woman can reach inside and feel for the string that runs through the cervix and comes out of the vagina. If no string is felt, a woman should get to her physician as quickly as possible and use a back up method to avoid becoming pregnant.
Now you know the answer of whether or not it is possible to become pregnant with an IUD, and the answer is yes. If you do become pregnant when having an IUD, it is important to get to a medical professional at once to be examined. There is a risk of miscarriage, pre-term labor or ectopic pregnancy so it is important to be aware of the dangers and if a woman thinks she has conceived, it is important to make an appointment to see an obstetrician for confirmation and proper care.