How Do I Calculate When I Ovulate?



To get pregnant, you need to have sex at the right time during your cycle. You need to know when you will be ovulating so you can make sure the sperm will be there to meet the egg.

Many women have a typical 28-day cycle, but not everyone does. Unfortunately, calculations based on this assumption could have you missing your fertile period if you are not part of the norm. You will need to calculate your cycle length.

Calculating the Length Of Your Cycle

You will need to keep track of when your period starts each month. Do not assume. Tracking the date for three or four months will give you the best estimate of when you ovulate.

The length of your cycle is not the number of days you bleed during your period.

Once you have the dates, you will need to count the number of days between the two dates on a calendar. "Day One" will be the day you start bleeding and the final day, of your cycle, will be the day before your period started the next month. If you would rather have us calculate the number of days for you, you can visit our menstrual cycle length calculator.  You will still need to have the past two dates that your period started, but at least you don't have to dig out a calendar to count manually!

The resulting number is usually between 21 and 35 days. If you have numbers that consistently fall outside of this range, you need to discuss the issue with your doctor.

If you have recorded the start dates for several months, you will want to repeat the calculation to make sure your cycle usually is the same number of days each month.

Occasionally, your cycle length can be thrown off by life issues like stress, starting or stopping medications, illness, and other issues. 

Calculating When You Ovulate

Unless you have medical issues that affect your ovulation, like PCOS or a luteal phase defect, you should be able to figure out when you will ovulate, based on when your next period should start.

Women typically ovulate 14 days before their period starts. Time to get your calendar out again and do the counting. Start at the day your period should start, and count backward 14 days. That should be when you will ovulate.

You can also use an ovulation calculator to give you a range of potential fertile days for the coming months. All you need to do is plug in your cycle length, and the rest is done for you.

Your Fertile Days

Now that you know when you should ovulate, you need to plan the babymaking dates. With optimal sperm health and friendly cervical mucus, sperm is quite hardy. After ejaculation, you may find that there could be sperm waiting for the egg five days after ejaculation.

With that in mind, to hedge your bets for successful fertilization, you will want to start having sex three days before you are due to ovulate. If your partner has no known sperm issues, like low sperm count, you should plan to have sex every day up to the day you ovulate.

Keep in mind, even if you had timed everything perfectly, only about 20% of couples get pregnant during the first month of trying. If you have been trying for a year with no success, and are under 35, you should consider visiting your doctor.

If you are 35 or older and haven't gotten pregnant after six months, a visit to your doctor is in order.


Other BabyHopes Articles

I See A Faint Line On My Home Pregnancy Test, Am I Pregnant?
I See A Faint Line On My Home Pregnancy Test, Am I Pregnant?
I See A Second Line! Home pregnancy tests use a sample of a woman's urine to detect the 'pregnanc...
Read More
EPO for PCOS (Evening Primrose Oil for Polycystic Ovarian Syndrome)
EPO for PCOS (Evening Primrose Oil for Polycystic Ovarian Syndrome)
Women with Polycystic Ovarian Syndrome who are trying to conceive are willing to do just about an...
Read More
How Long Do Sperm Stay Alive After Ejaculation?
How Long Do Sperm Stay Alive After Ejaculation?
Alright, ladies, let’s get personal. We’re gonna talk about sperm. Sperm is a vital part of the j...
Read More