Using a hot water bottle works well to relieve muscle cramp pain. But it’s not advisable to use it during the first trimester. This stage is very delicate for the fetus, and anything can easily result in a miscarriage or abnormalities in the baby.  When a lot of heat is provided to the body, the core temperature might rise, which isn’t good for the baby. So even when using a heating pad, use it for 10 to 15 minutes. If you feel overheated, hot, or sweaty, stop using the heating pad at once.