Despite the “fear mongering” we all get as teens, getting pregnant is actually not that easy. While one time is really all it takes, unless this time falls within a woman’s period of fertility, it can never result in a pregnancy.
In this post I’ll go through what this fertility window really is and what it isn’t. And I’ll also cover what is the best (and easiest!) way to figure out when you’re going through your period of fertility – whether you’re looking to get pregnant or to avoid it.
What is the “fertility window”?
Strictly speaking, your fertility window, or fertile window, is the period covering 6 days in your cycle in which it’s possible to get pregnant, if you have unprotected sex. These 6 days cover your ovulation day and the 5 days leading up to it.
How does that work?
- It covers your ovulation window – i.e., the 24 hour period following the release of the egg, in which the egg is viable, while it travels the length of the fallopian tube and before it deteriorates completely.
- And the maximum period of time sperm can survive in the uterus, in optimum conditions, which is up to 5 days.
Usually a woman will release only one egg per cycle, each month alternating the ovary from which it is released.
However, it is possible to experience cycles in which two eggs are released, one from each ovary. If this is the case, then the ovulation window would be up to 72 hours, instead of 24. This is because the release of both eggs might be separated from each other by up to 24 hours. (*)
Related content: Cycle Syncing How To For Glowing Skin, More Energy, Better Sex
MISCONCEPTIONS ABOUT THE PERIOD OF FERTILITY
1 – With a regular cycle your period of fertility will be the same every month
Your fertile window can be affected by several factors and even women with a regular cycle will experience shifts in the onset of their fertility windows. (*)
Any change to your normal routine can potentially affect your ovulation date, whether that’d be changes to diet, travelling, anxiety or stress levels. (*)
Studies show that although delays in ovulation are not very common, they do happen for every woman, regardless of the length or periodicity of her cycles. The timing of the fertile window can be highly variable, even for women with regular cycles. (*)
2 – Determine the period of fertility by counting backwards 14 days from the expected start of your next period
Meaning, if you have a regular cycle of 28 days (you expect your next period to arrive in 28 days), by counting 14 days before your expected start date, your fertile window would fall between days 10 and 17. The first day of your period being day 1 of your cycle.
The truth is only approximately 30% of women experience their fertile window within these guidelines. Over 70% of women will in fact reach their fertile window earlier than day 10 and quite a few even much later than day 17. (*)
3 – You’re fertile a few days before and a few days after your ovulation
The egg deteriorates within approximately 24 hours after its release from the ovary. It’s only possible to conceive within the 24 hours after the egg is released. After that the chances are statistically 0%. (*)
Having sex within the 5 days prior to the day of ovulation might result in pregnancy, especially within the 2 days prior to ovulation, but this is due to the fact that sperm can survive up to 5 days inside the uterus. Potentially it would be able to “meet” the egg a few days later, once it’s been released.
4 – It’s impossible to get pregnant while on your period
This is related to point number 1 regarding the high variability of the fertile window.
Even for women with regular cycles, studies show that there’s still a 1-6% chance of being in your fertile window on the first day of your period! (*)
Related content: PMS vs PMDD – And What You Can Do About It!
5 – You can get pregnant on any day of your cycle
This could technically be answered with a “yes” or “no”, depending on what you mean.
Strictly speaking, you can only get pregnant within the 24 hours after the onset of ovulation (when the egg is released by the ovary).
Since sperm can survive in the reproductive tract for up to 5 days, if you have unprotected sex in the 5 days before your day of ovulation, it’s also possible to get pregnant.
Outside of these 6 days pregnancy is not possible.
HOWEVER! As we’ve seen, the fertile window can move up or down quite a bit, even for women with very regular cycles. So, technically speaking, it wouldn’t be impossible for a woman to get pregnant on any given day of her cycle.
In other words, if you’re not sure when you’re ovulating and you want to be 100% sure you’re not going to get pregnant, the safest bet is to not have unprotected sex on any day of your cycle, period. Which, incidentally, might be a very good idea for several other reasons, if you don’t have a steady partner you can 100% trust.
The most effective way to determine your prime period of fertility?
So, as we’ve seen, the fertile window can move around a lot and be highly unpredictable. But there are several things you can use to try and determine your period of fertility, or fertile window.
Unfortunately there is no 100% reliable way to predict ovulation for a specific day – it is only possible to confirm that it has happened.
However, there are a couple of very good (and easy!) markers you can check for to try and determine if it’s getting close.
1 – Vaginal mucus
One of the very best indicators that your period of fertility is approaching is your vaginal mucus. Tracking your vaginal mucus is by far the best technique at your disposal – it’s very reliable and requires no special tools or training to interpret.
Your vaginal discharges might be clear or whitish, sticky or slippery, scant or plentiful. By keeping a close eye on the way your vaginal mucus looks and feels like to the touch, you’ll have a very good chance of knowing when you’re about to ovulate, or when you’ve entered your fertile window. (*)
This is because there is a significant rise in estrogen levels at the start of the fertility window. This estrogen increase will produce a specific type of cervical discharge that is very friendly to sperm. It helps to transport it and optimize its survival in the reproductive tract.
Just learning how to spot this type of peak fertility mucus can help you predict your ovulation window (those 24 hours within ovulation) with an accuracy of up to 90%. (*)
2 – Basal Body Temperature
I’ve written a whole post on how to chart and interpret your basal body temperature (BBT) for fertility awareness. You can check that out for a more in-depth look.
But roughly speaking, an increase in temperature (of at least three-tenths of a degree) that is sustained for at least 3 days usually precedes your ovulation day.
This is the best predictor, temperature wise, that ovulation is about to occur. (*)
Now, charting your basal body temperature can be a bit tricky at first and you should do it for a few months before you try to discern any kind of patterns.
That and the fact that there are many things that can affect your body temperature makes BBT charting a bit of a headache sometimes and not as reliable on its own.
However, when you cross-reference the information from your mucus discharge and your BBT chart you’ll have the best chances to be able to predict your ovulation window very accurately.
Related content: Your Basal Body Temperature Chart: What To Know & How To Read It
Fertility awareness is one of the gentlest and most user-friendly methods for birth control, regardless of whether or not you’re using other methods as well.
And, unlike other methods, it will not only teach you a lot about your own individual body and rhythms, it will also arm you with the knowledge to speed up your journey when trying to conceive.
Getting familiar with your menstrual cycle, noting your vaginal discharge and body temperature, and seeing how changes to your routine seem to affect those things.
I hope this helped to simplify the issue of determining your period of fertility, but let me know if you have any questions.
Anyone out there using fertility awareness to get pregnant or as birth control? Let us know in the comments!
