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A Fertility Monitor

When you’re trying to get pregnant, a fertility monitor is an important asset to you. If you don’t understand what they do or why they’re useful it can be difficult to see why you need one or decide which one to get. Today OvuSense is helping to shed some light on these devices, so you can take a more informed decision about whether they’re right for you.

What is Fertility Monitoring?

In this context, fertility monitoring has a very specific meaning: rather than give you an indication of your fertility in absolute terms, or diagnose conditions that can reduce fertility (or cause infertility), fertility monitors tell you when you are likely to be at your most fertile, giving you an advantage when you are trying to conceive.

They are several different ways they can do this, but they all rely on identifying when you ovulate so they can calculate your fertile window.

The Fertile Window and Ovulation

Your fertile window is the time in each menstrual cycle when you are most likely to get pregnant. It’s when the lifespan of sperm in a woman’s body overlaps with the twenty four hours after ovulation that an egg can remain viable for.

Sperm can survive for five days after sex, so if you try to conceive beginning five days before you ovulate, those sperm have a chance to reach the egg and fertilise it. That chance is modified by the speed of the sperms’ movement (‘motility’), and the quality of both eggs and sperm, which reduce both it’s lifespan and the odds of them combining successfully.

Monitoring Ovulation

It’s clear from this that the most important thing you can do to help identify your fertile days is to find out when you’re going to ovulate, and this is what fertility monitors do for you. The methods they use have specific strengths and weaknesses.

OPKs test the hormones in your urine, looking for the spike of Luteinising Hormone that causes your ovaries to actually release the egg that’s been maturing in them. These tests are widely available on supermarket shelves and easy to use (relatively speaking), which is an advantage. Unfortunately the disadvantages decidedly outweigh them.

OPKs can only tell you when you are ovulating, not predict when you are going to. This gives you less than twenty four hours of fertility in which to try and conceive. If you take the test at the wrong time of day, you could even miss this.

Fertility monitors that track your basal body temperature gives you more of an advance warning of when you’ll ovulate, but this method requires more manual work on your part, meaning there’s more of a chance for error to creep into the results. It also only provides an additional 24 hours of notice, which in the context of a six day fertile window, leaves a lot to be desired.

OvuSense uses a temperature sensor to track changes to core temperature. Our algorithm can use those changes to deduce your progesterone level, which tracks directly to your body’s preparations for ovulation. This means the OvuSense app can give you predictions days or weeks in advance of your fertile window, so you can make plans that will really boost your fertility.