Know Your Ovulation Period Using Calendar Method

Edited by aianne b., Charmed, Debbie, Lynn and 17 others

Meme Determine your Fertile Days.jpg

It's important for every woman to know when their ovulation takes place. Some people mistakenly believe that menstruation and ovulation are one and the same, but this is not true. Knowing when you ovulate will help you to either conceive or avoid pregnancy, if you are practicing natural family planning.

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  1. 1
    Know your menstruation cycle
    Either you have a regular or an irregular cycle. There are different ways to calculate when, during your cycle, you ovulate.
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  2. 2
    For women who have regular periods, either a 28 - 30, or 30 - 32-day cycle, as long as it's consistent, you can deduct 14 days before your cycle ends, plus or minus two days, to estimate ovulation
    For example, if you are on 32-day cycle, deduct 14 days, and you will have 18, plus and minus two days. Therefore, you can deduce that you are ovulating from day 16 to day 20 of your cycle. This means it is possible for you to become pregnant during these days your cycle.
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  3. 3
    For women having irregular periods, it will take longer, usually a minimum of six months before you can calculate your ovulation period
    The first step is to tally the number of days your menstrual cycle lasts for six months. Then you can look for the minimum number of days your periods lasted, and the maximum days it lasted. Then, deduct 18 days from the minimum days and deduct 11 days from the maximum days, and you will have your range of your ovulation period. For example, if you have 26 days for your minimum cycle, deduct 18 days from it and you will have 8, and if you have 30 days as your maximum cycle, deduct 11 days from it and you will have 19. That means that ovulation may be taking place between the 8th day and the 19th day of your cycle - plus add 2 days before and 2 days after.
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Ovulation Calendar Help: Sample Calendar of Ovulation for 28-30 Day Cycle

The internet offers "Ovulation Calendars", which will calculate your fertile days, according to your menstrual cycle. Just put in the last day of your menstruation, how many days your period lasts, and the length of your luteal phase. This is part of the menstrual cycle that starts at ovulation and ends the last day before your period starts. The information that you input will be used to create your personal chart, which will highlight your fertile days.

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List of sites that have Ovulation Calculators

Ovulation Calendar from

  • This ovulation calendar will allow you to input your last menstrual cycle, length of menstrual cycle, length of luteal phase and, if you are planning of conceiving, the gender of the baby1
  • Pros: Simple and neat calendar.
  • Cons: Visual indicators are in shades of green and orange. People with visual impairments will have hard time using the calendar.
  • Personal recommendation: Use it if you are able to differentiate the shades.

Fertility Calculator Calendar and Ovulation Calculator Calendar And Ovulation Predictor from

  • This ovulation calendar will allow you to input the date of your last period, length of menstrual cycle, and, if you are planning of conceiving, the gender of the baby1
  • Pros: Detailed calendar.
  • Cons: Other "not so important" information is included.
  • Personal recommendation: Use it.

Ovulation Calculator from

  • This ovulation calendar will allow you to input the date of your last period and length of your menstrual cycle.
  • Pros: Very simple calculator that gives the fertile days and the expected birth date.
  • Cons: Not many details on it, and it's full of assumptions as it calculates your fertile days for the entire year and the exact expected date of delivery.
  • Personal recommendation: Do not use it.

List of applications that have Ovulation Calculators

  1. 1
  2. 2

Tips Tricks & Warnings

  • Always begin from the day of your first drop of blood of your menstrual period as your first day of your cycle.
  • The last day of your cycle is the day before your first day of menstruation.

Questions and Answers

How accurate is the Last day of the period plus 14 days method?

This is less accurate than purchasing an ovulating tool in order to check on when you are effectively ovulating. The 14 day method is simply an estimate, which in turn is not as accurate or set in stone as it would be if you used the ovulating tool.

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Why 18 is deducted from a menstruation cycle to know safe period?

Ovulation occurs midway through every menstrual cycle. Deducting 18 would more or less be the time ovulation starts. It is 18 not 15 because you give some margin for your red days.

However, in most cases, the calendar method is not the safest method to use. It is because the ovulation pattern is not always extremely consistent and there are times when it occurs earlier than expected.

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What is minimum ovulation period?

It can be from 11 to 21 days after your menstrual period has stopped when you can be ovulating in order to become pregnant. Also 11 to 16 days before your period is when you can start ovulating.

If I am regular and reports are normal still not getting pregnant?

How fast can I conceive and my age is 25

If everything is in working order it can still take a woman up to a year to conceive. To maximize your chances of conceiving start charting your cycles and marking down the dates of your ovulation window each cycle.

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How do I get pregnant after having family planning injections for 9 months?

I was on family planning injections for 9 months..and now was found with a mass growth on my left ovary, early this year I went for treatment and it was done. Last month was found with another infection what do I do..I need a baby please help

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Some women get pregnant the first month after birth control injections stop but others wait at least three months for their first period. You seem to have issues with your ovaries and should ask your doctor to look into PCOS or polycystic ovarian syndrome. You can read more about ovulation help using cinnamon here

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How do I get a multiple pregnancy?

I have been on the inject-able for a year and I want to get a multiple pregnancy. How do I go about it. Any medication

The fertility oral drug Clomid can cause multiple births to occur, but even if you are prescribed the pill, it doesn't guarantee a multiple birth. Genetically, multiple births occur in families with other multiple births. You also can have IVF with several eggs implanted, however most Fertility Clinics will not transfer more than three eggs at a time for ethical reasons and the safety of the babies and mother as multiple births often end in premature births.

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Why may menstruation period become worse? I have been bleeding almost 2 weeks?

It's been 3 months since my menstruation period became worse. I was irregular but it's only 36 or 38 days cycles but since then my bleeding, if I have menstruation it takes two weeks. First week the bleed was spotting only and after a week it flows normal bleeding. How come it happens? What should I do to regulate normal. I am 38 years old now and I have only one 8 years old kid.

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Consider regulating your period cycles using cinnamon. Also you will want to speak with your doctor and ask about fibroids which can cause the bleeding your are experiencing.

How exactly can a woman with irregular periods use a pregnancy calendar?

I don't know how to use an ovulation pregnancy calendar accurately because my periods are never on time.. I think it was caused by: I have poly-cystic ovary disease that affects the regularity of my periods.

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Please check out this article on how to manage your PCOS. Once you regulate your period you can have a better chance at figuring out your ovulation window.

What if you don't know the length of your cycle?

My period cycle varies so much that I can't calculate it anymore I just wait for the signs. Sometimes it will not show up for a month or two and then suddenly returns. Please explain this for me

There are many factors that can contribute to an irregular cycle. About 30% of women have at some point in their life experienced an irregular menstrual cycle. This can be from stress to a hormonal balance. Once you can determine the causes, you can then treat them to maintain a regular cycle. Here are some VisiHow articles that can help you further:

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I'm an irregular, I still don't seem to understand the math in here?

I just had unprotected sex towards the beginning of my period. I have tried: Nothing at al,l I'm just scared I might fall pregnant. I think it was caused by: It's not really a problem .I'm just asking because I can't really understand the calendar thing

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The odds of you getting pregnant right before or after your period are very low. Sperm has a limited shelf life and ovulation occurs in the middle of a cycle. This means that your chances for becoming pregnant do not get higher until two weeks after the start of your menstrual cycle.

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Hi, when is my ovulation, my circle is 26 and my first date is today?

I have been trying for a second baby for about 3 years now, I am 43 and getting frustrated. I have tried: I have been taking pills to help with ovulation and I have ran a few scans my doctor recommended. I think it was caused by: I feel I am not ovulating, because my test shows that my tubs are free

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Your odds of getting pregnant at 43 are about 1%. You may not be ovulating properly even if you are taking fertility meds to boost an ovulation. Some women need a secondary shot medication to induce ovulation. Even then, the egg would need to be viable which after the age of 40, women have less viable eggs when they ovulate. If you are serious about getting pregnant as soon as possible, speak to your doctor about IVF. It is not the most desirable way to get pregnant but it may boost your odds for a better outcome. Keep in mind, that stress impacts our fertility. This is why so many women become pregnant when they adopt. Suddenly the stress of becoming pregnant is less prominent. Your window at 43 is rapidly closing so more proactive steps need to be taken as soon as possible.

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What to do to get a baby boy?

What to do to conceive baby boy and how to make my body alkaline. I have tried: Nothing. I think it was caused by: I don't know

Adding apple cider vinegar to your water can help with alkalinity. Dark chocolate also has an alkaline presence in our bodies. Companies like Santevia make Alkaline water pitchers. These have a special ionizer filter in the pitcher of water. There is an article in the answer section on this page that discusses how to get pregnant with a girl or boy. You should read it for help in attaining alkalinity.

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When should I start counting? My period came yesterday but it was light, but today is flowing well, when should I start counting?

My period came yesterday, but it was light but today is flowing well, please when should I start counting

You should start at the very first sign of spotting like you had yesterday. That would be day 1. Your fertile window would be two weeks from yesterday if you have a normal 28 day cycle.

I want you to help me know when I ovulate?

I use the cycle beads apps to track my cycle but whenever I enter the date if either my last cycle or the beginning of my cycle, I'm told I'm not within the apps working range which is 26-32 days.What do I have to do to be able to know when I ovulate?. I have tried: Nothings besides The cycle beads app.I was told it helps prevent pregnancies, track your period so I downloaded the app only to find out that it was and can be used by ladies who are within the 26-32 days range menstrual cycle.I don't even know what that (26-32 days range) means.. I think it was caused by: I don't really know and don't have any ideas.

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No app can help prevent pregnancy. Only birth control products and other protection methods will assist in not becoming pregnant. There are several more apps available in Google Play. Find the app that works for your cycle. From there you can determine when to use a barrier method or abstain completely to avoid pregnancy.

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What reason to have Bloated Abdomen? Is it connected with my Reproductive System? Does it affects me in my future life?

I am having this bloated abdomen which it makes me think why I have this kind of figure. It really bothers me because many says that I'm pregnant, but actually I'm not. I have my pelvic ultrasound last week and everything was in normal, though I have an immature follicle.

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I want to know the real father by the calculations pregnant problem?

I made a big mistake on the 22 and 23 September 2018 I sleep with my ex without using condom the whole night. then on the 28 September 2018 I also sleep with my husband without condom again and now I'm pregnant with no idea who is the father of my baby. when I went to the Doctor on the 13 December 2018 for baby scan, He told me that I have 10 weeks and 2 days pregnant. so can you please calculate for me that who is the real father? please. Yes I think its very different and I hope I can get help here. I have tried: I tried to calculate myself but don't get the answers. I think it was caused by: Its to be careless and to be stressed by my husband

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