The babyMed ovulation and fertility calendar and calculator helps you find the most fertile days of your menstrual cycle and identify your “Fertile Window.” Do you know if you are fertile? Take our online fertility test and find out.

Identify when you are most fertile

Women who know when they ovulate and when they are most fertile have a higher chance of getting pregnant during that cycle. Most other sites incorrectly calculate your fertile days and ovulation. babyMed has the most accurate ovulation calculator to determine your fertile window. It can also be used for early pregnancy detection.

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Improve your chances of getting pregnant

If you want to improve your chances of getting pregnant, you need to answer one simple question: "When do I ovulate and when are my fertile days?" Knowing exactly if and when you ovulate is the single most important information you need to know when trying to get pregnant (in addition to knowing that your partner has a healthy sperm count). You can only get pregnant from having sex on your fertile days, which are the 4-5 days before and the day of ovulation. If you know when you ovulate, you can also time sex better.

What causes ovulation to occur?

When your body is close to ovulation, LH levels start to rise. FSH, or follicle-stimulating hormone, causes the egg to quickly mature in preparation for the ovulatory phase when the egg is released from the ovary. The luteinizing hormone causes a gradual increase in estrogen. As you move from the follicular phase to the ovulatory phase, LH rebuilds the lining of the uterus. The uterine lining thickens and fills with blood and nutrients in preparation for egg implantation. This process occurs every month until an egg is implanted in the uterine lining or your period begins. Increased estrogen thins cervical mucus to help sperm travel toward the egg. Estrogen levels continue to gradually rise until they hit the tipping point that triggers an LH surge. LH surge is a drastic increase in estrogen that forces the follicle to release the mature egg. When the egg releases into the fallopian tube it is known as ovulation.

How accurate is this ovulation calculator?

This is the most accurate babyMed proprietary formula and was developed by an Ob-Gyn (who has over 30 years experience and has delivered 5,000+ babies) to help you calculate your fertile days to improve your chances of getting pregnant. The babyMed ovulation and fertility calculator will calculate your most fertile days to have sex, and it will also help you predict the precise day you will ovulate. It will also calculate the implantation day, when to expect the first pregnancy signs and symptoms, and when your pregnancy test could become positive. In addition, it will tell you the days you are less fertile, and less likely to get pregnant.

How do I use the ovulation and fertility calculator and calendar?

First, enter the first day of your last menstrual period. Then enter the average length of your menstrual cycles (average is usually around 28-29 days). If you don't know the exact length of your menstrual cycle or luteal phase, you can leave these at their default values (menstrual cycle: 28 days, luteal phase: 14 days). Try to record your cycle lengths if possible because that will help you to more accurately predict your likely date of ovulation.

What is the difference between the fertility window versus your fertile days?

The "fertility window" or "fertile window" consists of the 5-6 days during the menstrual cycle during which intercourse is most likely to result in pregnancy. You can get pregnant during these days, and your chances of getting pregnant increase the closer you have sex to the day of ovulation.  This fertile window extends runs for 6 days starting at 5 days before ovulation until the day of ovulation. Your most fertile days are the 4-5 days before and the day of ovulation.

Recent data show that ovulation could happen on several days of your cycle, even with a regular period, and ovulation does not always happen on the exact same day each month. Your fertility window is always 6 days, but he range of your fertile days as compared to the fertile or fertility window is potentially longer because your fertile days include all days during your menstrual cycle when you have the ability to become pregnant and takes into consideration a more flexible time period for ovulation. The fertile days assume different days for ovulation than the one calculated.  The fertile days are longer than the fertility window because ovulation does not always happen on the same day in each menstrual cycle but within a range of days. By calculating and identifying additional fertile days, not just the fertility window, we can provide couples with more flexibility to plan intercourse and more opportunities to conceive.

Calculate your fertile days and your fertility window HERE.

Can I get pregnant if I am having sex after ovulation?

Having intercourse the day after established ovulation is unlikely to improve your chances of getting pregnant. The egg lives only for 12-24 hours and sperm must be around when ovulation happens to improve fertilization and pregnancy. Increasing amounts of estrogen in the cervical mucus and reproductive tract of a woman approaching ovulation generally allows the sperm to live for up to 6 days.

Does ovulation always happen on the exact day of calculated ovulation?

Studies have shown that even in women with regular cycles, ovulation can happen any time, so "timing" of intercourse has never been shown to improve your pregnancy chances. You are probably not improving your chances of getting pregnant if you wait with intercourse until the temperature goes up or the OPK has become positive. You may already have ovulated by that time, and sex after ovulation is unlikely to get you pregnant.

In addition, you may improve your chances if you have sex once a day (as long as his sperm are OK) during the fertile 4-5 days before, and the day of, ovulation. In those rare circumstances when the man does not have enough sperm (oligospermia), the old rule of once every other day still holds true. 

  • Sex every day: 37% chance of pregnancy
  • Sex every other day: 33%  chance of pregnancy
  • Sex once a week: 15%  chance of pregnancy

How can we improve our chances to have a girl or a boy?

In addition to calculating your fertile days, this calculator also helps you improve your chances of having a girl or a boy by choosing either girl or boy or by default girl/boy in the drop-down menu. Following our recommendations could improve your chances of having one or the other, though it's not 100% sure.

For more tips to overcome fertility roadblocks and get pregnant faster, take our Fertility Course via email! 

Read More:
Due Date Calculator
Ovulation Calendar
Ten Tips to Get Pregnant Faster

Source: "Timing of Sexual Intercourse in Relation to Ovulation -- Effects on the Probability of Conception, Survival of the Pregnancy, and Sex of the Baby." Published in The New England Journal of Medicine (December 7, 1995 -- Vol. 333, No. 23). Allen J. Wilcox, Clarice R. Weinberg, Donna D. Bair