The Menstrual Cycle and Fertility: When to Conceive

When you’re trying to start a family, you’ll suddenly find yourself at the centre of a storm of well meaning advice from friends and relatives, all passing on well worn family secrets to getting pregnant. This is doubly the case if it’s taking longer than you’d like to conceive, and the onslaught of tips and tricks may not help you control the worry you feel about your chances of successfully getting pregnant.

Today we’re taking a look at the problem from a medical point of view, and giving you the insight you need to pick the best time to conceive, and ignore the myths, however well meant they are.

Fertile Windows

One of the terms doctors and fertility specialists might use casually is ‘your fertile window’. This is the span of days in each menstrual cycle where you stand the best chance of getting pregnant from normal, unprotected intercourse.

If you don’t know when yours is, and aren’t taking steps to identify it and ensure you’re trying at the right time then you’re reducing your chances of getting pregnant. The fertile window is defined by ovulation: you can only get pregnant when sperm can encounter a fertile egg in your fallopian tubes and inseminate it.

Sperm are manufactured by the male body when needed, but women’s body’s only get one (or rarely two) eggs in any one menstrual cycle, so to identify your fertile window, you need an ovulation predictor.

Predicting Ovulation

There are several different ways to predict when you’re going to ovulate, but one of the most accurate uses your Basal Body Temperature. This BBT is the low level your core temperature falls too when you’re sleeping for an extended period. If you can measure it daily for weeks and months, you’ll start to recognise small patterns of change that reflect your body’s internal processes. Specifically, ovulation is heralded by a drop of a tenth of a degree the day before, followed by a rise of the same amount over the following three days.

It can be arduous to collect and interpret that data, but modern technology can help. Modern fertility trackers include thermometers that can take your temperature automatically (and intimately) right through the night, to give you the most accurate results, as well as cloud computing links, to allow your temperature over time to processed into predictions of your next ovulation and tell you when to conceive.