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Birla Fertility & IVF
Birla Fertility & IVF

Period Calculator

Sync in with your periods! Tracking periods gives you a better idea and familiarity with your body, it also indicates if you are late or skipping your menstrual cycle. This period calculator helps you plan your month in advance by providing personalized results based on your inputs.


How To Use
Period Calculator?

This period calculator is easy to use and does not require any complex guidelines. Follow these simple steps to get the best-estimated results:

  • Mark the start date of your last menstrual period (LMP)
  • Enter the duration of the period
  • And lastly, enter the average length of your menstrual cycle

Once you enter all the necessary information, the calculator estimates the results including the fertile period, ovulation date and the timelines for the next period.

How To Use Period Calculator

Different Stages of the Menstrual Cycle

Typically, The menstrual cycle is  categorised into four phases based on their characteristics:

Menstrual Phase (Days 1-5):

This phase is defined by menstruation or the shedding of the uterine lining, and initiates the monthly cycle. Hormone levels fall during this phase, which causes the endometrium—the lining of the uterus—to shed and leave the body as menstrual blood through the vagina. The common symptoms of this phase are:

  • Abdominal Cramps
  • Bloating
  • Headaches
  • Mood swings
  • Tender breasts
  • Fatigue/tiredness

Follicular Phase (Days 1-13):

The follicular phase starts after menstruation. Follicle-stimulating hormone (FSH), produced by the pituitary gland, promotes the development of ovarian follicles during this period. Each ovarian follicle contains an immature egg. The endometrium thickens in anticipation of the possible implantation of a fertilized egg as estrogen levels rise. Here are some signs that can help you determine the second phase of your menstrual cycle:

  • Higher energy levels
  • Fresh and glowing skin
  • Increase in sex drive

Ovulation (Day 14):

Although it varies from woman to woman, ovulation usually happens around day 14 of the menstrual cycle. A spike in luteinizing hormone (LH) causes one of the ovarian follicles to release a mature egg during ovulation. During this stage, the egg is most fertile, with a window of around 12 to 24 hours following release for fertilization. In this phase, you can expect your peak fertility days and the following signs can indicate and help you determine when you can plan your pregnancy:

  • Cervical mucus changes
  • Heightened senses
  • Breast soreness or tenderness
  • Mild pelvic or lower abdominal pain
  • Vaginal bleeding
  • Sharp or dull cramp
  • Vaginal Discharge
  • Nausea
  • Light spotting

Luteal Phase (Days 15-28):

The luteal phase occurs after ovulation. The ovarian follicle that bursts becomes the corpus luteum, a tissue that secretes progesterone and a small amount of estrogen. These hormones help the uterus get ready for possible embryo implantation by supporting the thicker endometrium. The uterine lining sheds and a new menstrual cycle begins if conception is unsuccessful due to a drop in hormone levels. After the ovulation phase, if you don’t conceive, then you can experience the mentioned signs and symptoms:

  • Bloating
  • Breast swelling, pain, or tenderness
  • Headaches
  • Mood swings
  • Weight gain
  • Changes in sexual desire
  • Food cravings
  • Trouble sleeping

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How To Calculate
A Menstrual Cycle?

Calculating days to understand your menstrual cycle can be easy. The following steps may help you get a better understanding of how you can calculate your menstrual cycle:

  • Note the first day of your period and mark it on the calendar (when you are experiencing actual flow and not spotting)
  • Now, count till the day before your next period starts
  • Count the days between periods and monitor it for three months at least 
  • Using this, the average duration of your menstruation cycle can be calculated

Tracking period cycles

Why menstrual cycle is
Important To Track?

Tracking period cycles plays a key role if you are planning for conception. Also, if you know your body better and understand the boost of several hormones that are involved during the period, it can help you manage your cycle in a better way. 
If you notice a missed period or irregular cycle while tracking, it could indicate a health issue. It’s important to consult a doctor promptly for assistance.
In addition, tracking your period also helps in planning to have safe intercourse if you are avoiding an unplanned pregnancy.

Menstrual Period Tracker

What Is Menstrual Period Tracker?

There are several apps and trackers available on the internet and finding a reliable one can be a task. Period Tracker helps women keep a check on their reproductive health by knowing the prediction of ovulation days. It also aids in knowing the best time when a fertile window opens to plan pregnancy. You can trust this period calculator as it provides the most accurate and reliable tracking for your menstrual cycle.

menstrual cycle

How long is my cycle?

The menstrual cycle may vary from one woman to another depending on their diet and lifestyle. However, it is said that the average menstrual cycle is 28 days. If the period cycle is longer than 23 days and shorter than 35 days, it is considered normal. The menstrual cycle begins from the first day of your period till the last day before your next period. And, if by any chance you are experiencing an irregular period cycle frequently then consult a gynaecologist for expert advice. 

What if my periods are irregular

What if my periods
are irregular?

Women with irregular periods may find it difficult to track their ovulation days. However, most of the time, the ovulation calculator has proven effective in detecting the most fertile days even when you are experiencing irregular menstruation cycles. 
When irregular periods are uncommon and particularly long, then testing from month to month becomes necessary. Experts say that if you are not able to count your period cycle within 2-3 days when it is due, this can be an indication of irregular periods.

Signs of
Delayed Periods

If your period is late or delayed beyond its expected arrival date, several signs and symptoms may indicate this delay. These signs can vary from person to person, but common indicators of a late period include:


Prolonged stress can alter the synthesis and regulation of hormones, which may result in irregular or delayed menstruation.
Medical Condition:
Irregular menstrual cycles and delayed periods can be caused by several medical conditions, including polycystic ovarian syndrome (PCOS), thyroid problems, hormone imbalances, and problems with the reproductive system.
Missed Menstrual Bleeding:
A most obvious sign of a late period is the absence of menstrual bleeding beyond the expected date. Also, pregnancy can cause missed and delayed periods. 
Changes in Weight:
Substantial weight fluctuations, whether due to weight gain or loss, can impact menstrual cycles and hormonal balance, sometimes resulting in delayed periods.

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Myths & Facts

Myth- “PMS is not real


Premenstrual symptoms (PMS) are real and usually happen a week or two before the menstrual cycle. These symptoms typically occur because of hormonal changes. According to NCBI, over 20-40% of women experience premenstrual syndrome during their reproductive age.

Myth- “Headwash during periods can affect the bleeding flow


There is no such evidence or study that says the statement is true. In fact, personal hygiene is important and a warm shower can ease your menstrual cramps.

Frequently Asked Questions

Can Knowing Period Symptoms Help?

It’s important to note that not everyone experiences symptoms during menstruation, and individual experiences may vary from month to month. In addition, keeping track of symptoms and patterns can help individuals better understand their menstrual cycles and prepare for periods.

What is a Period Calculator, and How Does it Work?

A period calculator uses the length of your previous cycles to determine when your next menstrual cycle will begin. By monitoring your menstrual history, you can calculate your expected period dates and fertile window.

What are Common Menstrual Changes to Expect?

Variations in cycle length, shifts in the volume or consistency of the flow, shifts in premenstrual symptoms like mood swings or cramps, and shifts in the bleeding length are common menstrual alterations.

Why do Periods Get Delayed?

Hormonal imbalances, thyroid issues, PCOS, drastic weight fluctuations, stress, certain drugs, nursing, perimenopause, or reproductive abnormalities can all lead to irregular periods.

What Causes Irregular Periods?

Many things, including stress, diet or weight changes, hormonal imbalances, medical illnesses like PCOS or thyroid issues, extreme exercise, travel, or certain drugs, might cause a delay in menstruation.

Can Foods Affect the Menstrual Cycle?

Indeed, certain meals can impact hormone levels, inflammation, and general health, that can disrupt the menstrual cycle. Foods heavy in sugar or refined carbohydrates, processed foods, coffee, and alcohol are a few examples. Menstrual health can be supported by eating a balanced diet full of nutritious grains, fruits, vegetables, and lean meats.

Do you have a question?

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