The Number One Thing You Must Know Before Using NFP/FAM for Birth Control
Almost every story I hear about someone getting pregnant while using natural family planning (NFP) or the fertility awareness method (FAM) starts something like “Oh, yeah, we tried that, but within two months, I was pregnant!” While it’s true that this method requires more accuracy in practical use, symptothermal methods of birth control are 99.6 percent effective when used perfectly and 92.5 percent effective with typical use, according to a 2007 study published in Human Reproduction. However, most people more familiar with tracking their fertility to try to get pregnant and may not take the time to understand the rules for avoiding a pregnancy, which means they really aren’t using NFP at all.
Both NFP and FAM (the difference being that FAM allows for a barrier method during fertile times) are commonly referred to as charting because both methods involve tracking your fertility signs. At a bare minimum you need to track your basal body temperature, but if an unplanned pregnancy would be a major issue, it’s best to track the three most important signs: your temperature upon waking, the amount and consistency of cervical fluid, and the position of the cervix itself. Tracking these three signs on a fertility chart allows you to see the slight temperature shifts that happen in a your body after ovulation as well as the changes in the cervical fluid and cervix leading up to ovulation, critical for those trying to avoid a pregnancy.
Many people think they can start using NFP for birth control right away, and this is just not true. The number one rule you absolutely, unequivocally must follow is taking the time to get six consecutive months … yes, six … of charts before you can reliably begin to use NFP to avoid pregnancy. This is because fertility is governed by a very complex balance of hormones that can be affected by everything from taking cold medicine to not getting enough sleep the night before. It’s important to take the time to get to know your body and what your cycles really look like. You may think you know when you ovulate, but if you’re off by even 24 hours, it can mean the difference between one or two pink lines.
It’s also crucial that you use a nonhormonal backup method during the six months of baseline charting to prevent pregnancy. Trying to chart while on the pill or any other form of hormonal contraceptive will affect your fertility signs, and you won’t get an accurate idea of what your natural fertility cycle looks like. It’s also best to wait at least one month after coming off of hormonal birth control — more if you’ve been on it long term — to start charting so that your body has time to return back to its unique normal.