How Do You Calculate Your Period

Why Should You Know When Your Next Period Will Start

How do you calculate your monthly cycle? – Dr. Phani Madhuri

Knowing when your next period will start is useful for women to prepare for that day – there may need to be some minor adjustments to your routine. It can also be useful for booking gynecological exams, like a pap test which should be completed on a day you don’t have your period.

Knowing when to expect your next period can also help to prevent pregnancy, as your period days are the days you are least fertile .

General Overview Of The Menstrual Cycle:

The menstrual cycle includes several phases. The exact timing of the phases of the cycle is a little bit different for every woman and can change over time.

Cycle days

The first day of menstrual bleeding is considered Day 1 of the cycle.

Your period can last anywhere from 3 to 8 days, but 5 days is average.

Bleeding is usually heaviest on the first 2 days.

Days 6-14

Once the bleeding stops, the uterine lining begins to prepare for the possibility of a pregnancy.

The uterine lining becomes thicker and enriched in blood and nutrients.

Day 14-25

Somewhere around day 14, an egg is released from one of the ovaries and begins its journey down the fallopian tubes to the uterus.

If sperm are present in the fallopian tube at this time, fertilization can occur.

In this case the fertilized egg will travel to the uterus and attempt to implant in the uterine wall.

Days 25-28

If the egg was not fertilized or implantation does not occur, hormonal changes signal the uterus to prepare to shed its lining, and the egg breaks down and is shed along with lining.

The cycle begins again on Day 1 menstrual bleeding.

What Does It Mean If My Doctor Changes My Due Date

Your doctor may change your due date if your fetus is significantly smaller or larger than the average fetus at your particular stage of pregnancy.

Generally, your doctor orders an ultrasound to determine the gestational age of your baby when theres a history of irregular periods, when the date of your LMP is uncertain, or when conception occurred despite oral contraceptive use.

An ultrasound allows your doctor to measure the crown-rump length the length of the fetus from one end to the other.

During the first trimester, this measurement provides the most accurate estimation for the age of the baby. Your doctor may change your due date based on the ultrasound measurement.

This is most likely to occur in the first trimester, especially if the date estimated by the ultrasound differs by more than one week from the date estimated by your doctor based on your LMP.

In the second trimester, an ultrasound is less accurate and your doctor probably wont adjust your date unless the estimates vary by more than two weeks.

The third trimester is the least accurate time to date a pregnancy. Estimates based on an ultrasound can be off by as much as three weeks, so doctors rarely adjust dates during the third trimester.

However, its not uncommon for a doctor to perform an ultrasound in the third trimester if theyre thinking about changing your date.

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Q What Factors May Affect A Womans Menstrual Cycle

Several factors influence the date and flow of period. They include:

1. Diet And Exercise: Exercise and diet can affect your period and your chances of pregnancy. If you are training for an athletic event and are not eating properly, your estrogen levels can drop, halting your period.

2. Weight: Being too thin can also delay your periods, making your body think that you are not healthy enough for bearing a child. If you are overweight, excessive estrogen could build in your body, causing heavy or irregular periods.

3. Stress And Lifestyle: Stress can mess badly with your cycle. Lifestyle habits like drinking and smoking can cause irregular periods.

Do You Know These Facts About Menstruation

How to calculate your ovulation days, and days you haven
  • Most women bleed only about 80 ml or less during their periods.
  • At the time of ovulation you may have slight spotting and /or pain.
  • Do you know why women don’t get periods during pregnancy? When you get pregnant, hormones released in the body prevent endometrium from shedding off as bleeding and ensure thick lining of the uterus, which provides protection and nourishment to the fetus.
  • Menstrual cycle starts with menarche and ends with menopause.

Also Check: 90 Day Probationary Period Form

How Long Is My Fertility Window

The fertility window has a length of 8 days. The fertility window begins when sperm can theoretically survive within your body long enough to fertilise an egg. The fertility window ends with the maximum lifespan of an egg. As an egg can only survive 1 day outside of the ovaries, the window ends 1 day after ovulation.

How Much Blood Is Lost During A Period

The amount of blood lost during a period will vary from woman to woman, but, on average, a woman will lose about 6 – 8 teaspoons of blood per period. A loss of 80 ml or more, having a period longer than 7 days, or both, is considered heavy. However, most women have a good idea of whether or not their bleeding is within the normal range for them.

Also Check: Period Blood Stains On Sheets

Why Should I Track The Number Of Days Between Each Period

Whether you do it yourself or use an app, knowing how many days there are between each period can be a big help when it comes to feeling prepared and confident around yourâ¯period.

A few days before your period, you may want to start wearingâ¯ALWAYS Dailies pantylinersâ¯for extra protection and assurance that you wonât be caught off-guard by your period. ALWAYS Dailiesâ¯are super thin and flexible, so youâll barely even know you have one on.

When you know your period is due, be sure to stock up on period supplies likeâ¯TAMPAX. With a unique shape for better protection against leaks,â¯TAMPAX Pearl Compakâ¯tampons can boost your confidence during your period because you wonât be preoccupied with staining your knickers or having an embarrassing period accident. Combine this with your new knowledge of how many days there are between periods, and youâre golden!

Knowing when your period is coming can also help you to manage and prepare for any hormonal changes.

How Accurate Is Your Pregnancy Due Date Calculation


Due dates are just estimates, which differ from one pregnancy to another. According to a British study, only 4% are known to be born on their due date, and 90% are born before or after the due date . Most babies arrive in between 37 and 41 weeks of pregnancy.

The above methods of calculating your pregnancy weeks and months will give you a rough idea of how far you have been in your pregnancy. It is also important to understand that every pregnancy is different, and this is just a guide. Do not get stressed on the exact calculations.

However, you should consult your health practitioner if you have any questions about your due date and pregnancy week calculation.


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How Do You Calculate Pregnancy Weeks After Ivf

Calculating weeks of pregnancy and the due date is more precise during an IVF than it is during natural conception. This is because the exact date of embryo transfer is known. The insemination or egg retrieval procedure is scheduled before ovulation in IVF, thus making it more accurate.

The IVF due date is calculated by adding 38 weeks to the day the eggs were inseminated.

An alternative calculation is by adding 38 weeks to the date of transfer and subtract the age of embryos from this date. For instance, if it is a three-day embryo transfer, subtract three days, and if it is a four-day embryo transfer, subtract four days .

It, therefore, gives reliable estimated due dates. Also, with progressing pregnancy, the estimated due date could be more accurate based on ultrasound scans.

Knowing When Youre Going To Get Your Period Is Pretty Helpful

Maybe youâre planning a day at the beach. Maybe you have a sleepover with friends coming up. Or maybe you just want to know when to stash some extra Always Ultra in your bag, so youâre not caught off guard by your monthly flow.

Knowing how to calculate your menstrual cycle is easy and can give you a peace of mind.

So, hereâs how to do it.

How to calculate your menstrual cycle

In order to calculate your menstrual cycle, youâll need to learn how to track your cycle.

Donât worry. Itâs pretty simple. All you need to do is mark down when your period started on a calendar for a few months in order to figure out how to count your period cycle days and to calculate the average length of your menstrual cycle.

How to count the days in your menstrual cycle

Hereâs how it works. Mark the first day of your period on the calendar. The first day of your period is Day 1 of your menstrual cycle. Starting on the first day of your period, start counting.

The day before your next period is the last day of your menstrual cycle. Thatâs when you stop counting. Thatâs how many days you had in your menstrual cycle that month. For instance, if you got your period on June 5 and your next period came on July 2, your cycle length was 27 days that month.

Calculating your average menstrual cycle length

If you do this for a few months, youâll know how to count your period cycle days and youâll be able to figure out your average cycle length.

How to know when your next period is due

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What Happens In Each Menstrual Cycle

Why should you care about how to calculate menstrual cycle? It matters for many reasons. Some women just want to know when to expect the monthly flow. Others are trying to get pregnant and want to be able to track their ovulation timesthis begins by learning to track periods. Others just want to make sure everything is okay each month.

A menstrual cycle is much more than just a period. There are actually three very distinct phases throughout the month that create the full cycle.

Day 1 to 12: The Follicular Phase

This begins on the day you begin to bleed and continues until the day you ovulate. Certain hormones course through the body and prepare the ovaries to release follicles. One of those follicles will grow rapidly and turn into the ovum or the egg that is released during the ovulatory phase. The follicle secretes estrogen, and that helps build up the lining of the uterus.

Day 13 to 15: The Ovulatory Phase

In this phase, the egg is released into the fallopian tube. Once it is released, there is a 24-48 hour window during which it could be fertilized by male sperm. Cervical mucus increases during this time, to help the sperm swim up to the egg. If the egg is not fertilized, the lining begins to break down and the next phase begins.

Day 16 to 28: The Luteal Phase

Calculating Your Menstrual Cycle

Why you need to track your ovulation cycle if youre trying for a ...

Normal menstrual cycle lengths can range between 21 and 35 days. In order to calculate the number of days in your cycle, youâll need to keep track of when you get your period for a while. Hereâs how it works.

Step 1: Mark the first day of your period in theâ¯calendar. The first day of your period is Day 1 of your menstrual cycle. Do this for a few months, and youâll be one step closer to figuring out the average time between your periods.

Step 2: Add up the number of days in each cycle after youâve marked your period on the calendar for a few months. Then, divide this number by the number of periods youâve had in this time. This will give you your average cycle length .

Step 3: Now that you have this number, figuring out when your next period is due should be as easy as pie. Starting on the first day of your last period, just count forward the average number of days between your periods that you calculated in Step 2. This will give you the projected start date of your next period. Voilà !

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How Do I Calculate My Ovulation Date

The period tracker can also help you calculate your ovulation date! Your date of ovulation is when the egg is released from your ovary. You may have noticed on the calendar that in addition to menstruation being outlined in red, there are also dates outlined in blue. In our example above, those dates are August 17-21 and September 14-18. These dates are your peak ovulation days. In a 28 day cycle, the expected date of ovulation is day 14, i.e. two weeks before your next cycle begins. If your cycle is shorter or longer that date could change and thats where the period calculator comes in. These dates outlined in blue are your most fertile days, in the event that youre trying to become pregnant. Once released, the egg can live up to 24 hours while sperm can live for up to 5 days.

How Do I Calculate My Fertility Window

  • Calculate your ovulation day. Take your average cycle duration, subtract 14 days from this value, and add the remaining amount of days to the date your last period began.
  • Sperm can survive inside a woman’s body for 7 days, so subtract 7 days from your ovulation day. This is when your fertile window begins.
  • As the egg can only survive one day outside of the ovaries, add 1 day to your ovulation day. This is the end of your fertile window.
  • This time between these two dates is your fertile window.
  • Check your results, as well as find them for the next 3 months, with the Omni Ovulation Calculator.
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    How Many Days Are There Until Your Next Period

    Toâ¯calculate how many days there are between each period, you need to know how long your menstrual cycle is. The average menstrual cycle is 28 days, which means the average time between periods for most girls is 28 days. So, if you want a very general estimate of when your next period is coming, count 28 days from the first day of your last period. However, just be aware that 28 is only an average, so the number varies from girl to girl. Whatâs even more helpful is to work out the average for your individualâ¯menstrual cycle.

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