Planning pregnancy

Measuring your cycle

Because the first day of a period is such an easily recognized ‘landmark,’ this is the day we count as ‘Day 1’ of a cycle.

You then count all the days up to, but not including the first day of the next period. While 28 days is the average cycle length, you may find that yours is longer or shorter than this.

Ovulation

Fertility can be determined by planning your ovulation cycle which you can calculate by subtracting 14 to 16 days from the date of your next period. This is an approximation and may not be exact for every woman.

These calculations may not be accurate if your ovulation cycle is less than 21 days long or more than 35 days, or if your menstrual cycle is irregular from month to month. Please consult your doctor for more detailed information on ovulation and the most fertile time for you if you are trying for a baby.