Can You Rely on Your Birth Control for Years?

This is not a yes or no answer, as you may have suspected.  It’s really about HOW MUCH you can rely on your birth control method.  We’ve been discussing how effective different methods are over one year of use, but you may be wondering what to expect after 2, 5 and even 10 years of using the same method.  Keep in mind that people tend to hop between methods or have gaps in using birth control when they want to get pregnant or for other reasons.

Using the same numbers for effectiveness in one year for their calculations, Gregor Aisch and Bill Marsh created an interactive tool to show the likelihood of failure (an unintended pregnancy).  This tool was published in their article in the New York Times last week.  You can hover over any time point between 1 and 10 years to see the number of pregnancies expected among 100 women.

Now go play with the tool!  They have included 15 different birth control methods in their interactive tool.  Here’s a screenshot of how a few of the charts looks when I hover over the 10 year mark on the X-axis (I added the horrified and happy faces for dramatic effect):

NYT Tool Screenshot

The bolded number in the top-left represents the number of women who will have an unplanned pregnancy after typical use of that method of birth control, in this case for 10 years.  The solid line reflects typical use and the dashed line is perfect use.  If you need to refresh yourself on the difference between perfect and typical use, review this previous post.

Of course this tool does not take into consideration a few realities:

  • Women who are not using their method correctly and consistently will either become pregnant or switch methods.
  • Women who are using their method correctly and consistently will likely continue to use the method for a longer duration.
  • Women who use their selected method for a longer duration will take it more correctly and consistently over time as they become more experienced with the method.
Does this change your opinions of the different methods of birth control?  Did you like the interactive tool?  What else would you like to know about birth control?  Enter your comments below!

Remembering Your Birth Control

Many popular birth control methods are very effective if taken perfectly, but that effectiveness goes down drastically with typical use.  Perfect use means that the method is used consistently and correctly.  This is not as easy as it sounds for many people despite their best intentions.  For this reason, medical researchers have studied the effectiveness and failure rates of the various birth control methods.  For example, birth control pills are 99.7% effective with perfect use.  But in fact, 9% of women will become pregnant within the first year of using the pill and only 91% of women using the pill will have the desired effect of not becoming pregnant with typical use.  Even more drastic is the difference between the reported 98% effectiveness of male condoms with perfect use when the reality is that 18% of women using male condoms will become pregnant within the first year and only 82% will not become pregnant with typical use.  Many women and their partners may not be aware of these differences.

This distinction is important for two reasons:

First, you will want to consider this when selecting the right birth control method(s) for you.  To select the right birth control method(s) for you, prospective users (women and their partners) should be aware of the effectiveness of all the available methods.  In addition, you will want to be aware of how long the method works/how frequently you have to use it and potential side effects.  More information to come on this to help you make important decisions.

Second, you will want to use your selected method(s) of birth control consistently and correctly.  Now you may be wondering what it means to consistently and correctly use your birth control method.  Let’s use the most popular methods of birth control as examples again.

For birth control pills, this means taking a pill consistently every day and not missing days between pill packs.  Pills are taken correctly if taken at the same time every day.  Studies have shown that women may be missing up to 5 pills per cycle, on average, and many women have gaps between pill pack refills at the pharmacy.  It’s important to look at your daily routine and find a time when it would be easy to take your pill at the same time every day.  Is it easiest to take your pill… First thing when you wake up? As your morning coffee is brewing?  When you’re feeding the dog?  When you brush your teeth in the evening? Right before bed?  If you don’t have a daily routine or can’t find a time to consistently take your pill at the same time, the pill may not be a good birth control choice for you and there are other options that don’t require daily action on your part.  Once you find a time that works, you can set up convenient reminders.  Bedsider offers a free service to send you convenient text message reminders for your pill, patch, ring, or injectable birth control method.  Set up your reminder now.  Not only are these messages helpful reminders, they are also very entertaining:

Bedsider Text Message Reminders

Bedsider Text Message Reminders

For condoms, you need to be sure to use a condom consistently with each act of sex and correctly following these instructions from Planned Parenthood:

Hopefully this information will help you use your birth control to maximize its effectiveness!  As always, I welcome your comments, questions, and suggestions for future posts.


References:

  1. Trussell J. Contraceptive failure in the United States. Contraception 2011;83:397-404.
  2. Hou MY et al. Using daily text-message reminders to improve adherence with oral contraceptives: a randomized controlled trial. Obstet Gynecol 2010;116:633-40.
  3. Castaño PM et al. Effect of daily text messages on oral contraceptive continuation: a randomized controlled trial. Obstet Gynecol 2012;119:14-20.
  4. Pittman ME et al. Understanding prescription adherence: Pharmacy claims data from the Contraceptive CHOICE Project. Contraception 2011;83:340-5.