Good news, mama! While we do not encourage the use of heat patches on the abdomen area during pregnancy (so store your MenstruHeat away for now), the other patches should be good to go! Localised heat patches don't raise your core body temperature like saunas or jacuzzis, so they are generally safe to use during pregnancy. That said, we always recommend that you check with your gynaecologist for extra precaution as we're not able to assess your pregnancy condition.
If you do apply BackHeat/NeckHeat/KneeHeat, please remember to remove the patches periodically to give your skin time to breathe, especially if you have more sensitive skin. You should also not be using the patches overnight as you will be unable to monitor how hot it gets when you're asleep.