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Fertile Window

When you’re trying to conceive, you need to make sure you’re trying at the right time, under the right circumstances. Something you’ll hear about a lot is your ‘fertile window’ and how identifying it and predicting it is very important. But what is your fertile window?

Understanding all the different terminology involved can be overwhelming, but fortunately OvuSense can shed some light on the more confusing aspects of trying to conceive.


In brief, your fertile window is the time you have each month where you can conceive: where sex can lead to pregnancy.

If you’re not trying to get pregnant within your fertile window, you can’t succeed, so learning when it is is really important, especially if you’ve been experiencing some difficulty conceiving.

When is the Fertile Window?

Your fertile window is governed by two important factors: how long an egg remains fertile once it’s ejected from your ovaries, and how long sperm can survive in your body.

An egg survives up to 24 hours after you’ve ovulated, while sperm can survive for up to five days in the body, so depending on where the two people involved fall into that range, you have a fertile window of around six days in each cycle.

Identifying Your Fertile Window

Everyone is different, and that means that there’s no universal schedule telling you when your fertile window is – you have to look at your own body to learn the answers and learn when you ovulate. For the average woman, ovulation happens around sixteen days into their cycle, as measured from the first day of her period, but it can be anywhere between eleven and twenty seven days into the cycle. If you have PCOS or other fertility health issues, it can be even more irregular, or you may experience menstrual cycles without ovulating at all!

Any kind of irregularity in your cycle makes it all the more important to take advantage of those times when you do ovulate, which means careful tracking of your cycle to spot the key signs that give you a clue when you’re in your fertile window.

OvuSense uses a vaginal sensor to monitor your true fluctuations of progesterone throughout your cycle, unlike Basal Body Temperature monitoring devices which take oral temperature measurements to predict when ovulation occurs. The advantages of using OvuSense's method include a greater level of accuracy when measuring temperature, as well as the ability to use up-to-date data to predict your current month's cycle, as opposed to BBT devices which predict your cycle using data from the previous month. This allows users to get an accurate prediction of their ovulation date even if their cycles are irregularly from one month to the next!

To learn more about your cycle and hear from Ovusense customers visit ovusense