Aaron: Everyone always talks about condoms when they're talking about preventing pregnancy, and condoms are good.  But nowhere near perfect.  The pill is even better, but you want to know what's amazing?  Intrauterine devices, or IUDs. They were pretty rare for a while, but they're making a resurgence. They're also the topic of this week's Healthcare Triage.

(Intro)

The pill seems to be the choice of most women who want longer acting birth control, i.e. not a condom, but birth control pills still have a 9% failure rate. This means that if 1000 take a pill regularly, about 90 will become pregnant in a year. That may surprise many of you, who assume the pills are pretty much infallible. And they're good, don't get me wrong.  But, they require women to take them regularly, and many fail to do that, and some of them get pregnant.

If 1000 women use and IUD for a year, on the other hand, about 2 to 8 will get pregnant, far fewer than the 90 on the pill. And condoms? About 180 women will get pregnant. Way worse.  

IUDs aren't rare worldwide. About 170 million women use them, making them one of the most common forms of reversible contraception. They are the birth control of choice for more than 15% of all women who are married or living with a partner. Far fewer American women use them though, maybe 8.5%  That's partially because there were serious issues with the old IUDs when they were first introduced, and I'll talk about all of that next week.  

But now IUDs are really, really safe. They're easier to put in and easier to use. Here's a telling study and it's entitled Differences in Contraceptive Use Between Family Planning Providers in the United States Population: Results of a Nationwide Survey and it was published in the journal Contraception this year.

Researchers surveyed female family planning providers between the ages of 25 and 44 years old, including physicians and advanced practice clinicians via an internet-based survey from April to May of 2013.  Family planning providers were compared to female respondents of the same age from the 2011-2013 National Survey of Family Growth.  

Here's what they found: while 11% of the general public said they used IUDs, about 40% of family planning providers did.  What do they know that you don't?  

There are a number of different kinds of IUDs.Some are completely inert and are just a foreign body in the uterus. Others contain copper, which has local effects in the cervical region.  Some also contain hormones and release them slowly over time.  All of them, though, work to decrease sperm motility and their ability to survive long enough to make it to an unfertilized egg.

IUDs, in general, make the uterus very unfriendly to sperm. That's how they work. The copper kind slowly release copper ions all over the uterus, and those kill sperm. The hormonal IUDs do the same thing with hormones, by thickening the cervical mucus and making the uterine walls difficult for sperm to traverse.  

Copper IUDs last longer, maybe twelve years. The hormonal IUDs last about 3 to 5 years, but the hormonal IUDs work a bit better, like a .2% failure rate versus a .8% failure rate.  

Want to know how one gets placed?  Here's what happens in the office. Women are put in stirrups, as if for a usual pelvic exam. Once the doctor visualizes the cervix, he or she grabs it with the forceps and pulls it to straighten it out. Then, the doctor inserts a metal rod to gauge and measure the depth of the uterus. Finally, they insert the IUD itself with an insert guide, and once it's in the uterus, they pull back to extend the arms of the device.  Then they push it all the way in carefully. And then, pull back the insert guide, making sure to leave the string that's attached to the IUD hanging out of the cervix.  They cut it a few centimeters from the end and measure the length so they can track it in later visits.

Some women say that the insertion can hurt or be uncomfortable; others don't. Far fewer complain about pain once it's in, though.  

As I said, they work really, really well.  Sometimes they fail because they come out with a period and a woman doesn't notice.  And sometimes a really hardy sperm makes it all the way to the egg anyway, and the egg implants.  

Expulsions happen about 3 to 5% of the time. They happen more often in adolescents, between 5 and 22% of the time, depending on the study. Women using all kinds of IUDs can expect changes in their menstruation especially in the first few months of use.  

The copper IUD can sometimes cause heavier bleeding or cramps, that can be treated with over the counter drugs. Women using a hormonal IUD can have a decrease in bleeding over time until they are only spotting or not even bleeding at all. Some women don't like that, but others love it. Talk to your doctors so you can understand what changes to expect.  

And, look, I shouldn't even have to say this, but I'm going to anyway-the IUD will not protect you from Sexual Transmitted Infections.  It just protects you against pregnancy.  You still need a condom to prevent STIs.  This is especially true in the period after the IUD is inserted. You're actually at a slightly increased risk of getting a sexually transmitted infection in those first few weeks. So, protect yourself.  

But, if you're looking for a long term, reversible for of contraception, that really, really works, you ought to consider talking to your doctor about an IUD.

One of the problems, the expense, has been reduced by many public health care programs and the Affordable Care Act. It might be easier than you think now. All of those female family planning providers are getting them for a reason.  

Healthcare Triage is supported in part by views like you through patreon.com, a service that allows you to support the show through a monthly donation. We'd especially like to thank our honorary research associates, Cameron Alexander and Qadeem Salehmohamed. Thanks Cameron and Qadeem!

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