An intrauterine device (IUD) is ideal for some busy moms because it requires really no care or thought—you have it inserted and then forget about it. Even better, you should be able to get pregnant immediately after having an IUD removed. The efficacy rates of the following IUDs are about equal at 98- to 99-percent effective.
A progestin-releasing IUD (such as Mirena) administers the hormone progestin (about one-fifth the dose found in birth control pills), lasts for up to five years, and is as effective as sterilization in preventing pregnancy. In addition, it can reduce menstrual blood flow by up to 90-percent after a year, prevents menstrual cramps, and may even slow or prevent the growth of fibroid tumors of the uterus. It's also safe for nursing moms.
The copper IUD is a hormone-free, T-shaped device wrapped with a fine copper wire (ParaGard® is a good example). The wire releases a tiny bit of copper (less than in the average daily diet), which immobilizes sperm and prevents fertilization. It will last for up to 10 years, making it very cost effective. Some copper IUDs can also be used as an emergency contraception method. There's a downside to the copper IUD in that it can increase cramping and bleeding, especially during the first year of use.