rhythm method

If you are familiar with natural birth control, you may have already heard about the rhythm method, also named the knaus-ogino method.

This is one of the most popular and most effective forms of natural birth control. Many couples use natural methods instead of barrier or hormonal methods for a number of reasons, including medical limitations, enjoyment, and religious beliefs.

Whether you've heard of the rhythm method of contraception before or, in contrast, you have no clue about what it is and how it works, you shouldn't miss our special explanation. Once you read it, you'll have enough information to consider trying it or, instead, look for alternatives.


Mark your calendar

The rhythm method of contraception is another type of family planning through which you should be able to determine your fertile days, either if you are trying to become pregnant or avoid it—this method is helpful for both! It requires just a simple calculation revolving around your menstrual cycle. The purpose of it is for you to be able to identify when you may be ovulating, based on, at least, a 6 month-study of your period. This method does require some long-term research because you need to monitor your cycle. 

It is important because a woman actually only has a few days of the month during which she is fertile—just after she ovulates. The rest of the time it is nearly impossible for sperm to reach an egg that it can fertilise. So by tracking ovulation, you can plan your intercourse around your fertile days. However, it is important to remember that sperm can live for several days within your body, so if you want to avoid getting pregnant, you won’t want to have sex anytime during the few days before or after ovulation. This is why you need to pinpoint very precisely when you are ovulating. If done correctly, it is between 80% and 87% effective. Not bad, considering that it’s free and natural!


Let's do some maths

You will have to do some basic calculations in order to plan when you can have unprotected intercourse, don't worry, the rhythm method won't send you back to school to do some maths once again. It is only simple addition and subtraction. Here’s how you do it:

  • For at least 6 months (but preferably closer to 12), count the number of days in a complete menstrual cycle. The first day of your period is day 1, and the last day before you start your next period is the final day.

  • Find the shortest menstrual cycle you had within the time and subtract 18 days from the number. The number you get will be the day that you would be most likely to get pregnant. If the cycle is 27 days, and you subtract 18, you will be most fertile on the 9th day of the cycle.

  • Find the longest menstrual cycle from the time period and subtract 11 days from that number. The result will be approximately your last real day of fertility within the month. If the cycle is 31 days and you subtract 11, your last fertile day will be day 20 of your cycle.

  • If you don’t want to get pregnant, you shouldn’t have unprotected sex during these days. You should also leave an additional 2 days at the beginning and at the end of your calculated time during which you avoid unprotected sex. This is because your calculation will only be approximate, and also because ovulation can vary a little bit month to month.

  • As long as you continue using the rhythm method of contraception, you should continue to keep track of your cycles and update your numbers each month. Don’t just keep using the numbers from calculations that you did months ago. That way, you can be as accurate as possible.


Is the rhythm method for you?

All family planning and contraception methods have advantages and disadvantages, and the rhythm method is no exception. As always, you should consider these carefully and talk to your partner before you decide to begin using the method.

First, the rhythm method, along with some other natural family planning methods, is compatible with a number of religions that disapprove of barrier and hormonal contraceptives. Second, as long as you keep track of the right time of the month to have sex, you have no pills or contraceptive devices to worry about, which means uninterrupted lovemaking. Finally, there are no health or safety concerns, as you are making no changes to your body. 

However, if you and your partner want to be able to enjoy spontaneous sex, you may want to consider using another method. Or, you could simply use a condom or another barrier device during your fertile days. Also, if you are very serious about avoiding pregnancy, this may not be the option for you. Finally, long-term record keeping is required in order for the rhythm method to be effective, so you should make sure that you are ready for such a commitment.


There’s another way

If you really like the idea of using the rhythm method, but don’t quite trust your record-keeping skills, you can always buy an at-home ovulation kit to help you keep track of where you are in your cycle. Remember, though, that you should avoid unprotected sex for a few days before you are actually ovulating because the sperm could still be hanging around when your egg drops. So you’ll still want to keep up with your monthly numbers, but the kit can provide you with more accuracy. They can be a little bit expensive, but you can inquire at your local pharmacy.


There are many reasons that couples would choose the rhythm method of family planning. Whether it’s for health reasons, religious reasons, or simply to enjoy love making without having to worry about devices, the reasons for using this method will have to be your own. If you’re considering the rhythm method, talk to your partner about the pros and cons, and consider your lifestyle together. You should also keep in mind the amount of risk that you’re comfortable with, as this method is not quite as effective as not-natural birth control methods.