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There is a window of about seven days in her cycle when a woman is most likely to fall pregnant. This is called the fertile period and is the phase of her menstrual cycle just before and when she is ovulating. Our calculator will easily help you to work out when you are ovulating and, therefore, when you are most likely to fall pregnant.
There are many ways to work out where you are in your cycle, and a calculator like this one is a great help if you are trying to get pregnant or perhaps trying to avoid it.

Other ways to help work out your cycle is to test the levels of the hormone LH in your urine. If the levels go up, you’re ovulating. There are also many signals from the body that women can track by being aware of the changes you go through during your cycle. Mood swings, bloating and mucus discharge from the vagina are all signals that your period is about to start. This will help with counting the days of your cycle and working out how long before bleeding starts you are ovulating.

In order to fall pregnant, a woman must be in the fertile period of her cycle. If you aren’t ovulating, you are very unlikely to conceive. By using our Fertility Calculator, you can work out almost exactly when you are ovulating. For women with regular menstrual cycles, the days will be almost completely accurate. However, if your cycle isn’t that regular, the calculator will show you an estimate regarding the days that you are ovulating. You can still use this information as a guide to help you fall pregnant – or avoid falling pregnant if that’s the case.

Most women are in the fertile phase for a full seven days of their cycle. However, their most fertile day is the fourteenth day before the start of their menstrual period. This is due to the levels of hormones released into your body at various points during your cycle. The pituitary gland releases hormones to start the ovulation process, and the peak of the process is on that fourteenth day.

How to calculate when you are in your fertile period?

Our calculator is very easy to use. Simply enter the number of days in your cycle, plus the day on which your last menstrual period started. The calculator will then work out an estimate of your fertile period based on a stable cycle. If your cycle isn’t completely regular, you can still use the information from the calculator as a guide to help you conceive.

A woman’s full menstrual cycle can last anywhere from 21 to 40 days. The length of your cycle depends on how long it takes for a follicle to mature once stimulated by FHS and estrogen. Essentially, it’s the time between your menstrual period and ovulation that changes. This time frame can be anywhere between 10 and 29 days. After ovulation, most women will begin to bleed in 11 to 16 days – 14 days being the most common.

Signs of ovulation

Many women are actually able to tell when they are ovulating by paying careful attention to their bodies. If you have an irregular cycle, looking out for the obvious signals is the best way to work out when you are at your most fertile.
The main signs are:

  • Mucus discharge from the vagina
  • Low body temperature
  • Increased libido
  • Pains or pangs on the side of your lower abdomen

By using our Fertility Calculator in conjunction with looking out for these signs, you’ll be able to work out quite accurately when you are in the fertile period of your cycle.

If you’re hoping to conceive, working out when you are ovulating goes a long way to helping the process. By knowing when you are going to ovulate, you can plan your lives accordingly. If you and your partner lead busy lives, you can schedule business trips and the like around your cycle in order to maximize your efforts for conceiving.

You can also use our Fertility Calculator to figure out the approximate date of your baby’s conception. All you need is the date of your last menstrual cycle and the calculator will work out when you ovulated before that and, therefore, when you were most fertile.

On the other end of the scale, if you’re actively trying not to fall pregnant, working out your cycle can be an effective method of contraception. This is called the rhythm method of contraception and works best for women who are incredibly regular in their cycles.

Readers’ questions:

When does my fertile period end?

The fertile period ends after ovulation actually occurs. During the fertile window, the body discharges a white mucus from the vagina, which resembles moisturizing cream. As the discharge fades, so does your fertility for that cycle.

Do I still have a fertile period if I take hormonal contraception?

No, women who take the pill or other forms of hormonal contraception do not ovulate so they do not have a fertile period. These methods of contraception actually work by inhibiting ovulation in order to prevent pregnancy.