Intrauterine devices (IUDs) provide trouble-free, long-term contraception. An IUD sits in the uterus and alters the uterine microenvironment so that sperm cannot pass to the Fallopian tubes to fertilize a released ovum.
Of the four IUDs available now in the USA, the Paragard (up to 10 year use) is an inert plastic, wound with fine copper wire. Copper ions in the uterine fluid kill sperm and prevent final maturation of the uterine lining. The Paragard has a pregnancy rate of less than 1% per year and can be used as emergency contraception for up to five days.
The Mirena (5 year use) and the smaller Skyla and Liletta (3 year use) devices release minute amounts of progestin, thus also preventing sperm motility into the uterus and preventing the lining from developing. They also have less than 1% failure rates.
None of the IUDs alter ovulation, nor do they release meaningful amounts of hormones into the bloodstream; thus the IUD user will have no systemic side effects. None of them should be viewed as abortifacients, as all three prevent sperm from getting to the egg.
The continuous progestin in hormonal IUDs is helpful to patients with dysfunctional uterine bleeding and adenomyosis (endometriosis in the uterus). They are also useful as a progestin delivery source for menopausal women.
The IUDs are extremely safe but require thoughtful precision in their insertion. One hears of “migrating” IUDs or of IUDs “pushing through” the uterus years later, which puzzles me; what force is applied to the IUD to cause it to move? More likely, “migrating” IUDs were misplaced initially. To prevent this I always measure the uterus with ultrasound just before insertion and to confirm proper positioning immediately afterwards; using this method, I have never mis-placed an IUD.
During IUD insertion, a tiny string is left hanging in the cervical canal for eventual removal. To remove, the string is grasped with a tiny clamp to slowly release and remove the IUD. This procedure is almost imperceptible.
If you would like an IUD, we can sit and consider the choices, determine by ultrasound which device will fit you, check for STDs, and place the device at your next visit. The insertion is less trouble than you think, you can leave the office for work, and contraception is immediate.