How Pregnancy Happens + Rhythm Method

How to Use the Easiest, Cheapest Contraception Method

Understanding your menstrual cycle is key to not panicking. For one, the kind of panic caused by suspected unwanted pregnancy is a legitimately traumatizing experience for many, and it is my sincere wish for as few people to undergo it as possible. For another, the stress caused by panicking will delay your menstrual cycle, meaning freaking out about unwanted pregnancy will make your period late regardless of your actual pregnancy status. If your goal is to understand what’s happening in your body as quickly and accurately as possible, it’s essential to not panic.

For your purposes, here are the basics. A “typical” menstrual cycle is 28 days, with day 1 being the first day of your period. Pregnancy occurs when a sperm cell fertilizes (or comes in contact with) an egg; however, contrary to fear-based sex ed classes, eggs are not available (or viable) throughout the whole cycle. Around day 14 of a typical cycle, an egg will be released from the fallopian tubes and start the journey towards the uterus, where the egg can potentially meet sperm; this journey from tube to uterus, called ovulation, can take from 1 to 5 days. Once in the uterus, the egg only survives one day. However, sperm can survive up in the vagina for up to 5 days. So, if sperm enters the vaginal canal five days before ovulation or 1 day after, pregnancy can occur.

The Rhythm Method: The Easiest, Cheapest Contraceptive Method

In a lot of ways, this knowledge can be comforting. For an average cycle, there are only about six days where sex can lead to pregnancy-- the five days before ovulation and the day of. The rhythm method is a method of contraception wherein people track the length of their cycles and estimate when they’re ovulating, which allows them to not have sex during those ~six most fertile days. 

“The rhythm method” explains why people say it’s harder to get pregnant from period sex; since most people ovulate around day 14 (or anywhere from day 11 to day 21), sperm entering a body on day 2 of a cycle (which is day 2 of your period) could only survive until ~day 7, which would be before an egg is released. The same logic can be used for sex right before your period; sperm entering your body on day 26 wouldn’t survive until the next egg was released. 

Unfortunately, very few people have a typical 28-day cycle. In their teenage years, people with periods usually have unpredictable, ever-changing cycles. For teens, a “normal” cycle can be anywhere from 21 to 42 days long, and every cycle can be a different length. This means that it’s hard to tell when you’re ovulating because you don’t know when the “middle” of your cycle will be, and if you don’t know for sure when you’ve ovulated, then it’s hard to know which ~ six-day span you’re fertile for. This is especially difficult when your cycle is changing from month to month, since a week you’re not fertile one month may be your most fertile week in the next month. This variability is why it is possible to get pregnant on your period, though unlikely. If your cycle is, for instance, only 20 days long, and you have sex on day 5 of your period, that sperm will still be viable on day 10 when you ovulate. 

For this reason, I really encourage people not to rely on the rhythm method as their primary method of contraception, since it’s notably unreliable and even less reliable for teens. If 100 couples used the rhythm method as their main form of contraception for a year, 24 of those couples would be pregnant by the end of that year. 

I cannot in good faith call the rhythm method a real form of contraception, let alone an effective one. However, it is the only option on this list that can truly be done with no money, transportation, or intervention by others. If you must rely solely on the rhythm method, there are ways to make it as effective as possible.

1.     Download Clue, or something similar

Clue is a cycle tracking app that allows you to note facets of your cycle, including the beginning and end of your period. Doing so regularly will allow you to tell how long your cycle is generally, which is essential information if you want to tell when you’re ovulating

NOTE: Now, in a Post-Roe world, online cycle tracking is not always safe. If possible, use a pen and paper to safely and discreetly track your cycle. You can read more here.

2.     Take note of your discharge 

You should always be aware in strange changes in your discharge, since it’s the number one indicator of vaginal infections/STDs. However, you can also use it to tell when you’re ovulating. You’re at your most fertile when your discharge is thick and slippery, like egg whites. You’re at your least fertile when your discharge is thin and watery. If you can stretch your discharge between two fingers, it’s safe to say you are in your fertile window. 

3.     Try limiting your sex life to the days around your period.

The days around your period are when you are the least likely to get pregnant. If possible, try limiting your sex life to those days. However, if you don’t think that’s possible, be sure not to have sex in the six days around when you’re ovulating, since that is when you are most likely to get pregnant. By using the steps 1 and 2 above, you should have some idea of when your fertile window is. 

            As mentioned, I do not recommend the rhythm method as a form of birth control. However, sexual health is precarious, inaccessible, and stigmatized for a lot of people. If you need a form of “contraception” that is completely free, discreet, and entirely up to you, this is the only one.

For another method that’s free and discreet that your partner controls, learn more about PULLING OUT below

"Pulling Out" + If Pre-Cum Gets You Pregnant