Are you a woman on the Pill, patch, shot, or IUD who is interested in learning more about your cycle? You’re probably not alone. The popularity of fertility-awareness based methods of family planning is on the rise, likely fueled by women who are sick—literally—of enduring birth control side effects, and looking for more natural methods that distribute the responsibility of family planning more evenly between the man and the woman.
Perhaps you’ve started to think that Natural Family Planning (NFP) or a Fertility Awareness-Based Method (FABM) might just fit the bill, and so you’ve given thought to dipping your toes into charting your cycles. But perhaps you’re also loathe at the moment to completely give up your current method of birth control for fear of an unintended pregnancy occurring while you figure out how all of this fertility-awareness stuff works. So, the question you’ve probably asked yourself is “Can I chart while I’m on birth control?” The short answer is sure, or perhaps, maybe. If your question is “Can I measure my body’s full cycle and hormone health while on birth control?” The answer to that is no. But it’s much more complicated than one-word answers, so let’s look closer.
First off, charting your cycles is more than marking the calendar every month when you start your period. Any method—yes, even if it’s a supposedly high-tech app—that asks nothing more of you than to track your period is the Rhythm Method (RM) cloaked in code. The RM was quite literally your grandmother’s form of family planning, and was notoriously unsuccessful at preventing pregnancies, precisely because the only information it used was the date of a woman’s period in order to predict when she could expect to ovulate that cycle.
In contrast, modern methods of Fertility Awareness and Natural Family Planning use a host of biological information unique to you to help you determine in real time (no futuristic guesswork, here) what the state of your fertility is on any given day of your cycle. Modern FABMs rely on the cyclical changes that a woman’s body undergoes as her menstrual cycle progresses through its various phases. Whether a woman is looking to postpone or achieve a pregnancy, the most important piece of information offered by FABM is when she is ovulating. In fact, the whole point of charting positively hinges on this. If a woman and her partner are looking to postpone pregnancy, they will avoid sex on the days leading up to, on, and immediately after ovulation; if they are looking to get pregnant, well, those days are time to get down to business.
So here’s the thing about attempting to chart while on birth control: Most forms of birth control (aside from non-hormonal methods like the condom, the diaphragm, or Copper IUD) function primarily by suppressing ovulation. Literally, these birth control methods will stop your ovaries from releasing an egg, and with no egg for sperm to fertilize, there can be no conception or pregnancy.
But there is a catch. Did you notice how I said that birth control functions primarily by suppressing ovulation? That’s because sometimes a woman will still ovulate while on birth control. This is a phenomenon known as “breakthrough ovulation.” When breakthrough ovulation occurs, it is, in fact, possible for conception to occur if a woman and her partner have sex while she is ovulating. It is then that the secondary functions of the birth control method may take effect, either by thickening the woman’s cervical mucus to prevent her partner’s sperm from reaching the egg, or by thinning the woman’s uterine lining so that if a sperm does get through and conception does occur, the fertilized egg will not have a hospitable environment in which it may implant. In this case, the fertilized egg will pass with that month’s menses—and while this is technically not a “miscarriage,” as medically, a “pregnancy” does not begin until implantation occurs—because a unique life begins at conception, this is a morally fraught result of birth control if it does, in fact, occur.
So, how often does breakthrough ovulation occur? Estimates vary, and they differ between different forms of birth control. For the combined (estrogen and progestin) pills, a woman may ovulate up to 28% of the time (so, out of every 12 cycles, about 3 of them could be ovulatory); for the progestin-only pill (or the “mini-Pill”), a woman may ovulate between 33-65% of the time; for the IUD (specifically the Mirena), that rate may be as high as 75% after the first year of use.
Therefore, in theory, if you are charting while on some form of conventional birth control, you may be able to see signs of breakthrough ovulation occurring. However, you will have no way of knowing for sure whether those “signs” are due to true ovulation (i.e., the effects of your own hormones) or the effects of your birth control. So, even if you do a great job of capturing your “fertility” data each day while on birth control, you just can’t be sure that the information you’re gathering while charting is really telling you anything of use about what may—or may not—be going on in your body.
Even marking the start of your bleeding each month while on birth control is fairly useless, as that event depends on outside factors influencing your cycle — like which pills you’re taking in your pack during a particular time of the month. If you see and record signs of what you believe is a possible breakthrough ovulation, then perhaps the bleeding you experience that month is a true period, as for bleeding to be a true menstruation (rather than a “breakthrough bleed”), the bleeding must be preceded by ovulation. Again, though, you will have no way of knowing for certain, and your chart cannot be properly interpreted while you are still on birth control.
If You Want to Learn More About Your Body, Just Make the Switch
So, the question must be asked, to what end would you want to chart while on birth control? Maybe you’re looking to see whether you can commit to checking for signs of fertility every day, like taking your temperature each morning, or remembering to check the toilet paper for cervical mucus each time you visit the bathroom. Personally, though, I would think that you’d be more committed to remembering to do these things if you had to do them, rather than attempting these practices on a pseudo-trial run. I know that even though I began charting when my husband and I were engaged, I was much more committed to charting after our marriage when the risk for pregnancy was finally real. Of course, it is possible that the partial information gleaned from charting while on birth control could be of use to you personally, but it is difficult to see why it would matter, practically speaking. And, speaking as a Couple-to-Couple League certified instructor of the Sympto-Thermal Method, I would be unable to give you an official interpretation of such a chart.
The truth is, if you are serious about learning more about your cycle and planning your family without hormones or implants, it only makes sense to ditch your conventional birth control altogether. It will require a time commitment from both you and your spouse as you learn your chosen method, and also possibly a short period of abstinence while you figure out this new lifestyle—but as women who’ve made the switch from hormonal birth control to fertility awareness will tell you, it is all absolutely worth it in the end. If you’re already committed enough to the idea of planning your family the natural, side-effect free way that you’re seriously considering charting, why not start right away, and find yourself a certified NFP/FABM instructor today?