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A Fertility Calculator

Calculating when you’re going to be fertile can give you a real advantage when you’re trying to conceive, but it’s not an easy job. We’re looking at how fertility calculation works, to help you make the right decisions, and boost your chances of getting pregnant when you want to.

When Are You Fertile?

A woman’s fertility varies throughout her menstrual cycle – at some points it’s impossible to get pregnant as the biological factors that allow pregnancy are simply not in place. At other times, those same factors all align and give you a boosted chance of a natural pregnancy.

The key to identifying when you’re fertile is knowing when you ovulate. The day you ovulate, a fertile egg is released from one of your ovaries and it remains viable for up to 24 hours. If sperm can reach it inside that 24 hours, then they may fertilise it and though that doesn’t guarantee pregnancy, you have passed one of the major hurdles.

Sperm can survive up to five days in a woman’s body after sex, so your fertile window begins five days before you ovulate: from this point until twenty four hours after ovulation, sex has the best possible chance of resulting in pregnancy.

Ovulation and Fertility

This means that ‘calculating fertility’ really means ‘calculating ovulation’. If you know when you’re going to ovulate, you can predict your fertile window and plan around it, boosting your chance of conceiving in that cycle.

If your menstrual cycle is very regular, calculating when you ovulate is less challenging. Ovulation occurs at (roughly) the midpoint of your cycle, and finding this when your period is every 28 days isn’t difficult.

You can pin down the date your ovulation more precisely by taking a confirmatory test. If you know which day of your cycle you ovulated on once and your cycle is regularly, you can be confident about it happening on the same day again. Don’t note the date: note how many days after your period you ovulated. Next cycle, you can feel confident you will ovulate fourteen (for example) days after your period.

Irregular Cycles

If your cycle is irregular it’s hard to calculate in the same way. Even if you confirm in one cycle that you ovulated fourteen days after your period, next time it could be ten days, or twenty!

This is where OvuSense can help. Rather than working with pure numbers, we track the conditions inside your body. Our sensor records your core temperature, and tiny changes in that temperature can be translated by our algorithm into how long until you ovulate and therefore when you will be fertile. This lets you plan to conceive, even if you have very irregular cycles, or conditions like PCOS which affect your fertility.

Learn more about fertility and pregnancy here