Ovulation calculator

How to calculate the fertile days?

If you want to know when your fertile days will be, observe your body carefully. In order to calculate them successfully, you should know the average duration of your menstrual cycle and the number of days your last menstruation lasted for.

How does the ovulation calculator work

The ovulation calendar will calculate and indicate when your next infertile and fertile days and ovulation begin. However, remember that there are various factors which may lead to their shift.

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fertile days


Free application - Bella Calendar

Do you want to know when your next fertile days are? Download our application to your smartphone, enter the data in your personal mobile Calendar and have your cycle under constant control!

When are my fertile days?

  • Increased body temperature - regular measurement of temperature will enable you to assess whether your ovulation is actually due to start. During ovulation, body temperature increases to around 37 degrees.

  • The amount of mucus increases significantly during ovulation and its consistency changes from runny to thick, resembling egg whites.

  • Stomach pains usually occur on the first day of bleeding and may transfer towards the lumbar area. Usually the pain eases during the menstruation.

  • Cervical changes - during fertile days, the cervix is softer leans to the front.

What influences the shift of fertile days?

Menstruation should appear regularly, in appropriate cycles. Observe your body and if there are significant irregularities, it is best to go the doctor. What disturbances are we talking about?
- abundant bleeding lasting for a few hours
- menstruation starts more often that 21 days
- menstruation lasts longer than 7 days
- pains in lower abdomen and bleeding appear suddenly, completely unrelated to the menstruation.

Period calculator

Do you want to know when your next menstruation is? Check our menstruation calendar which will help you calculate it.

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