November 30, 2012

Contraceptive Series Part 3: Mirena, The Hormonal IUD

by novanilla

This is the third installment of my Contraceptive Series, in which I will provide accessible information about Mirena, the hormonal IUD option. This article will provide information about the basics of Mirena— everything you need to know when making a decision about what contraceptive is best for you.

So how does it work?

Mirena works by releasing low levels of progestin into the body. There is debate around whether the hormones remain local in the uterus or if they spread through the body. As I discussed in the first installment, when I introduced the series, progestin works differently from estrogen. It prevents pregnancy by thickening the cervical mucus, which slows down and inhibits sperm from swimming to an egg. It can also suppress ovulation, though it does not always do so. It is just as effective as estrogen. Its usage in the uterus makes it much more effective than the pill, when actual rates are studied. Although “ideal use” puts these each at 99.9%, pills can fail due to forgetfulness or lack of education about proper usage. Mirena is simple for anyone to use and will always reach that 99.9% effectiveness.

Who should use Mirena? Who shouldn’t?

As with every contraceptive, it’s important to research whether or not it’s good for you before you get it, especially with devices like Mirena, Paragard, or Implanon, that require insertion and removal by a health care provider. It can be especially hard for women without health insurance to acquire these methods. Before using any method, research is necessary.

Mirena is good for those who want or need long-lasting birth control that is effective with little to no hassle, private birth control no one will see, and progestin-only birth control free of estrogen. Mirena is popular among college students who have a hard time keeping up with changing pharmacies and doctors depending on what part of the country they are in. This hormonal IUD is also popular with mothers who want to space children apart or are thinking about more permanent birth control options down the road, people with too heavy of periods or cramps to consider Paragard, busy women who are stressed about keeping track of birth control, and queer women who don’t want to bother with birth control when they don’t often (or ever) sleep with men, but want more protection than condoms, or want a lighter, more comfortable period. Unlike Paragard, it can be used for purposes other than contraception since it has a hormonal component.

Women who do not want to use hormones should not use Mirena. Although it is low-dose, it is still a hormonal option and will affect the body. Its low hormone doses only partially suppress ovarian activity, which can lead to ovarian cysts (though these sometimes disappear after the device’s removal) and ruptured follicles. This can cause problems for those with fibroids or endometriosis. If this is a concern, talk with a gynecologist to decide if this is a good option or not. It may be better to choose a different long-term and low-maintenance option like Implanon that will not be placed in the uterus.

What happens once I get it?

Mirena contains hormones, and therefore, all the side effects that may occur after, while using other hormonal methods, can also occur with Mirena. Periods may become lighter, but they can also stop or become irregular in other ways. Cramps are often suppressed, a benefit for many women with painful periods. Some women may experience emotional distress, lack of interest in sex, breast pain, or other problems common with hormonal birth control.

Although it’s also incredibly important that a woman with Paragard remove the device immediately upon becoming pregnant should it fail — a woman with Mirena must do so arguably even more urgently. It has all of the impacts of an IUD on pregnancy (ectopic pregnancy, for instance) plus the effects of hormones, which are not yet fully known. Mirena’s manufacturer, Bayer, has stated that some side effects have been seen during the small number of births that do occur after Mirena fails, such as a more masculine look to a female fetus’s exterior genital area.

Wait… my doctor said I can’t get Mirena or Paragard. Why?

This is a really common problem for young women. If you’re under 35 and you’ve never been pregnant before, it’s likely that a lot of gynecologists will turn you down. This is not because it is unsafe. The American College of Obstetrics and Gynecology officially recommends IUDs, even for young women. The reason that many doctors are leery of giving IUDs to young women is partially because of myths of infertility left over from old, dangerous IUDs of the mid-20th century, but also because young people are generally more at risk for STIs. The string that is connected to the IUD comes into the vagina, and if an STI is acquired, it can spread up the string, leading to problems like Pelvic Inflammatory Disease. However, no matter what your age, it is up to you to defend your right to acquire Mirena or Paragard if you know one of these options is best for you. Advocate for yourself — there are gynecologists who take your research seriously and will give you what you want and deserve.

Next time, I’ll be covering Implanon which was referenced in this article. If you have questions about Mirena that I did not address here, either send me a message or ask in comments!