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How to Work out Ovulation With Irregular Periods

Your periods may be irregular for a variety of reasons; however, when you have an irregular menstrual cycle, it is hard to prepare for your period and to predict when you are going to ovulate. This knowledge is especially important if you are trying to conceive. The ovulation window--the time during which an egg can be fertilized by sperm--is a relatively short (12-14 hours) and thus, identifying when you ovulate is important in order to plan your conception around the few days before it happens.[1] Keep in mind that an irregular period can be a symptom of other medical problems that should be addressed prior to conceiving (such as polycystic ovarian syndrome, prediabetes, or thyroid dysfunction), so you should see a doctor before attempting to conceive.

Method One of Two:
Tracking Your Body’s Signals

  1. 1
    Check your body temperature. Your basal body temperature (BBT) allows you to track when you are ovulating. You must take your BBT every morning for several months in order to track a reliable trend in your cycle.[2].
    • Take your BBT first thing in the morning and record your temperature in a small calendar on your bedside table. You should take this reading before you get out of bed to prepare for the day for it to be most accurate.
    • Your BBT remains stable throughout the first half of your menstrual cycle, then it drops when there is a surge of progesterone signaling that ovulation is about to start. Your temperature then rises half a degree when you are actively ovulating. The most optimal time to have sex is two days prior to ovulation, right before the temperature rise. It takes time for the sperm to get to the egg. If you have sex the day of ovulation, you have only a 5 percent chance to conceive.[3][4]
  2. 2
    Track your vaginal discharge/mucus. Your vaginal discharge, which consists of cervical mucus, provides important clues about where you are in your menstrual cycle. Hormonal fluctuations cause the consistency and color of your cervical mucus to change.[5].
    • Fertile discharge is clear and thin, and it has the consistency of egg whites. You have this kind of discharge when you are ovulating.[6]
    • Discharge during the rest of your menstrual cycle tends to be cloudy and white and may be thick or thin.
    • It is not uncommon to have brownish discharge for a few days after your period. This is the result of your vagina cleaning out old blood. Usually, you have less discharge after your period ends.
  3. 3
    Check your cervix. Your cervix, the tunnel between your vagina and uterus, changes throughout your menstrual cycle. The texture and position of your cervix lets you know if you are ovulating.[7]
    • Probe your cervix with one or two fingers daily and write down your observations about its position and texture to start tracking trends.
    • During the first part of your menstrual cycle, your cervix is hard and low. As your body prepares to ovulate, your cervix softens, opens slightly, and shortens to allow sperm an easy access to your ovum.
    • You may need to reach your finger several inches into your vagina before you feel your cervix. Once the tip of your finger touches a donut-shaped opening at the end of your vagina, you have reached your cervix.
    • If you are unsure how to feel your cervix, read more here.
  4. 4
    Test your hormone levels by using an ovulation test kit. Ovulation test kits reveal your level of luteinizing hormone (LH). Your LH level spikes right before your ovary releases an egg, indicating your fertile time.[8].
    • Like a pregnancy test, an over-the-counter ovulation test kit requires a urine sample to determine your levels of LH. The test turns positive the day before ovulation occurs; thus, you may need to do several tests daily around the time of ovulation to identify the correct day.[9]
    • Checking your cervix and tracking trends in your vaginal discharge can help you determine when you should take an ovulation test. Also, ovulation kits provide guidance about when to check urine based on how irregular your menses are.

Method Two of Two:
Using the Ovulation Chart

  1. 1
    Start a chart on the first day of your period. Ovulation charts are useful for combining results from your vaginal discharge and basal body temperature (BBT) that can be used to identify trends in your cycle. Although you are having irregular periods, start the tracking on the first day of your period.[10]
    • The first day of your period is day one. If your menstrual cycle is irregular, then you may bleed every 21-35 days for 2-7 days, perhaps with some spotting.[11]
    • Number each of the days preceding your period. When you start a new period, then that is your new day one.
    • Figure out the number of days your cycles approximately last for a few months. Then try to see if there is an average number that emerges as time passes.
  2. 2
    Chart your BBT every day. Create a chart that has temperatures ranging from 97.0 to 98.0 degrees Fahrenheit in increasing increments of 0.1 degrees on the X-axis and the days of your cycle on the Y-axis.[12]
    • Put a dot on the temperature that corresponds your BBT reading under the corresponding day of your cycle. This way you can see if there are fluctuations from day to day in your BBT.
    • Connecting the dots allows you to track trends more easily from a visual perspective.
    • There is a drop and then a dramatic spike in your BBT when you ovulate, indicating the two most fertile days of your cycle.
    • You can find a sample chart at[13]
  3. 3
    Add descriptions of your vaginal discharge for each day to the chart. Create an easy to understand key describing your vaginal discharge. For example, D can indicate the dryness that occurs after your menstrual cycle, B can stand for a period, R can stand for regular white discharge, and F can stand for stringy, clear fertile discharge. [14]
    • Compare your descriptions of your discharge against observations from previous cycles and see if your discharge changes consistency within an average range of dates. This can give you a better idea of how your irregular cycle lengths may vary.
  4. 4
    Observe averages in your ovulation charts to get a better idea of when you are fertile. With irregular periods, it can be frustrating and hard to find patterns that indicate when you are most fertile. Your ovulation chart helps you see if there are certain trends that emerge.[15]
    • With irregular menstrual cycles, it can be hard to get a clear cut average, but you can at least better estimate when you evaluate within a range of a few days.
  5. 5
    Use your ovulation chart to track period lengths. A frustrating aspect of having an irregular menstrual cycle is being unprepared for your period. You can use an ovulation chart to get a better idea about your cycle length based on averages from previous cycles.[16]
    • You can also see an average of bleeding days emerge from your data, helping you to better prepare for your period when it comes.

Community Q&A

Add New Question
  • It's been 43 days since my last period. Am I pregnant?
    Answered by wikiHow Contributor
    • The best advice would be to take a pregnancy test. Unless you have been using birth control that causes you to not have periods or have irregular periods, then it is a possibility that you are pregnant.
    Thanks! 15 3
  • Could I be pregnant if my period is late by 3-4 days?
    Answered by wikiHow Contributor
    • It's too soon to tell. Your period might just be irregular or changing. It is normal for your period to be a little late sometimes, especially in younger females.
    Thanks! 39 14
  • I had unprotected sex during my fertile window and my period is 7 days late. Am I likely to be pregnant?
    Answered by AbigailAbernathy, Top Answerer
    • Probably. Now is a good time to take a pregnancy test to be absolutely sure.
    Thanks! 10 3
  • I need help on how to calculate my most fertile days, I tried the method in this article last month but I am still not pregnant and I am so worried.
    Answered by wikiHow Contributor
    • Getting pregnant takes time for many people, even with regular periods. However, you could also try using the Clear Blue easy ovulation predictor, as it will show a smiley face when you are fertile and a blinking smiley face when you are ovulating. Then, have sex for the next several days after that. It would be an excellent idea to talk to your doctor about your worries, as there are fertility specialists who can help you.
    Thanks! 50 39
  • How do I calculate my ovulation time?
    Answered by wikiHow Contributor
    • Apps that track your period make this very easy. I suggest downloading Flo, Life, or Clue.
    Thanks! 13 7
  • Is it normal to have a period twice in a month sometimes?
    Answered by wikiHow Contributor
    • Yes. It all depends on your body. If you are concerned about it, ask your doctor next time you are there for a check up.
    Thanks! 7 3
  • Can I get pregnant on my period?
    Answered by AbigailAbernathy, Top Answerer
    • It's a slight risk, but still a risk.
    Thanks! 4 1
  • I have PCOS and I took Metformin for two months to regulate my period, then I stopped. Afterward, my period is irregular again. What should I do to have a regular period?
    Answered by AbigailAbernathy, Top Answerer
    • Because you have PCOS, you will suffer through long periods of having irregular periods and you will need medication. Talk to your gynecologist.
    Thanks! 5 3
  • My period is over a week late, and I took the morning-after pill after I had sex. Could I be pregnant?
    Answered by wikiHow Contributor
    • A late or missing period is not always a sign of pregnancy. Take a pregnancy test. If it comes up positive, schedule an appointment with your doctor to confirm the pregnancy.
    Thanks! 16 20
  • My period's date is changing every month. How can I get pregnant?
    Answered by Tom De Backer, Top Answerer
    • Remember that even though sex doesn't guarantee pregnancy, the entire system is intended to lead to pregnancy. Humans, and a few other species, also have sex just for fun, but nature's basic goal is to create offspring. So you needn't really do anything in particular to get pregnant. Make sure to relax, enjoy the intimacy, and keep repeating it, you'll get there. Ask your doctor for advice and help if it doesn't work out naturally. Finally, ovulation occurs midway through the menstrual cycle, so keep your schedule free those days and nights.
    Thanks! 4 4
Show more answers
  • Can I detect whether I am pregnant nine days after my last time having sex?
  • How can I work out ovulation if my period is irregular? Is something wrong if I have a lot of discharge when I don't have my period?
  • Is it possible I am pregnant if I have not had a period in over two months? I have irregular periods, so I am not sure, and the test shows negative.
  • I did not get my period last month and I am not on contraceptives. Is it normal?
  • How do I figure out my peak ovulation if I had an abortion recently?
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  • The most effective time to conceive is the six days leading up to the day of ovulation and the day of ovulation.[17]
    1 Helpful?  2
  • After your egg is released, it will typically survive for a day but sperm, once released, can survive for up to a week.[18]
    2 Helpful?  1

Expert Review By:

Obstetrician & Gynecologist

This version of How to Work out Ovulation With Irregular Periods was reviewed by Lacy Windham, M.D. on September 23, 2015.

415 votes - 75%
Co-authors: 17
Views: 648,042

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