Is it a twin line flashing on your pregnancy test strip? Congratulations Mommy-would-be! Definitely, you are wondering how old the little darling inside you is? Just after your heart settles from the horripilation, you delve down in the PREGNANCY MATH. Check out these simple tips to calculate Pregnancy in weeks and months or an easy Indian pregnancy month calculator.

Before you encounter questions just quickly recapitulate if you remember your Last Menstrual Cycle (LMP) which is a vital point.

When is my due date?

How many weeks Am I Pregnant?

How to calculate pregnancy months in India?

In which trimester what sort of care should I  take to keep myself and my baby in the best health condition?

How to calculate pregnancy weeks to months?

So here we are with all the easy solutions and answers to your questions about how many months pregnant you are. Pregnancy can be a challenge, but it is so much easier to relax and take care of your little one when you know your pregnancy calendar precisely.

You may be interested in how to get pregnant fast.

How many Days, Week & trimesters:

It is best to consult a gynaecologist at the earliest who can determine all details based on CRL or Crown Rump Length determining the gestational age of the baby.

Average Duration


The Fear of Due Date

Pregnancy is an amazing time, but waking up every morning wondering if today is the day you’re going to have a baby can make it difficult to properly enjoy the pregnancy. Quite frankly, it can be a pain in the bum.

Not only that but trying to work out when in your pregnancy you are is a nightmare too; if you’re like most women, you don’t even know what your due date is! Most people we know personally who were pregnant had no idea that their due date was just approximate and not set in stone as many assume.

Giving birth can also be a very nerve-wracking experience. What if something happens? What if something goes wrong? A lot of questions run through your head. Again, very stressful and adds to the pain.

This guide teaches you how to determine exactly when you will give birth. You’ll also be taught about things like trimesters, developments and problems associated with the trimesters. It doesn’t matter if it’s your first baby or second baby, this guide will teach you everything!

The formula for self-calculation:

1st day of LAST Menstrual Period (LMP) + 40 weeks

Example – If your 1st day of LMP was 20th Feb 2018 then

Solution – 20th Feb 2018 + 40 weeks = 27th November 2018 is your due date of delivery

The general formula of calculation by Physicians:

9 months + 7 days of your 1st day of LMP

Solution – 20th Feb + 9 months = 20th November 2018

20th Nov 2018 + 7 days = 27th November 2018

However, out of 20 babies, only 1 takes birth on the due date. Usually doctors use the LMP to decide your weeks to months pregnancy due date. This is because even if you remember your date of intercourse which resulted in pregnancy, it is not always the same date on which the sperm met the egg and fertilisation has occurred.

Still not able to calculate your Pregnancy in weeks and months? Use Budding Star’s Pregnancy Due Date Calculator for knowing how many weeks pregnant you are just by entering the first day of your last period.

CRL or Crown Rump Length in getting gestational age of the baby:

Crown Rump Length refers to the measurement of the length of a human embryo or fetus. Generally, the length is considered from head to bottom of buttocks. This is done by ultrasound scan. The size and length determine the exact gestational age of the baby. On every trimester ultrasound should be done to know the position and other specifications of the baby.

You may be interested in symptoms of a baby boy or symptoms of baby girl.

Weeks Chart of Pregnancy Months:

Divide 9 months by 3 trimesters

First Trimester1-13 weeks + 6 days1 to 3
Second Trimester14-27 weeks + 6 days4 to 6
Third Trimester28-40 weeks + Date of delivery7 to 9

Week is just calculated like your age. The first year of baby birth is considered as 0 year and respective months. And by the time baby complete one full year and drop to the second year he/she is said 1 year old. Similarly, when you are on your 2nd week you are been said as 1 week pregnant by a physician. So the formula is;

  X+1 week = X week

Example – 12 +1 week = 13 week

13 is medically considered as the 12th week

 Trimesters & Developments & Problems:

  • First trimesterWeeks 1–13 are typically included in this early trimester. Because many women are unaware that they are pregnant during the first few weeks of pregnancy, this is considered a short trimester. The mass of the cell or embryo starts taking shape and the first organ that develops in the fetus is the Heart. In the third week, you can hear the heartbeat of the tender life inside you. Take care of your nutrition as the same is nurturing the baby too. It is the toughest phase hence morning sickness, nausea, and weight loss may happen.
  • Second Trimester – Weeks 14–27 are typically included in the middle trimester. Many mothers regard this as the easiest and most comfortable trimester. During these months the fetus gets a well-defined face, eyes, eyelids, toes, hands, nails and other organs also develop. These days you feel much better. You may gain weight, get a baby glow, feel more relaxed as by now you are used to and know your next step.

FAQ: how many scans are there in the II trimester?

Scans differ in each pregnancy owing to age, medical history or weight, but usually, one ultrasound is done in the 2nd trimester after the first one in the 1st trimester   

  • Third Trimester – Weeks 28–40 of your third trimester may be included. However, many women go into labour before week 40, and some may remain pregnant for another week or two. During these months the baby can hear, respond to light and touch, can kick and move heads. You are about to deliver and so need to be very cautious.
Come along! Let us explore the world of Pregnancy week by week by looking at fetal development, moods & symptoms with do’s and don’ts and pregnancy-related frequently asked questions.

Strictly maintain Dos & Don’t by Doctor. Take proper precautions, don’t miss out on any medicine, and take medical help without any delay in case you doubt any complications.

Week 4

Your baby is the size of a mustard seed four weeks after your last period. Starting this week of

pregnancy, a pregnancy test would be positive. In addition, if you had an ultrasound near the

end of the week, you might see a gestational sac.

Week 8 

Your baby is moving on its own, but it is usually too early for you to notice. You’ll soon be able to count the finger and toe rays that your baby is developing this week. What are your thoughts? 

Week 12

Your child is the size of a clementine, also known as Cuties. Your doctor or midwife should

be able to hear your cutie’s heartbeat around this time using a doppler. Isn’t it a wonderful

sensation? Your baby’s brain is also completing structures that were present at birth, but

there is still much work to be done.

Week 16

This week’s starfruit is about the size of your baby, and starry-eyed may describe how you feel about learning your baby’s gender. A few fortunate parents will be able to learn this soon, but the majority will have to wait.

Week 20

At 20 weeks of pregnancy, your baby is about the size of a banana or approximately 10 inches long from head to toe. They weigh around 280 grams and are growing rapidly. By this stage, your baby’s body is becoming more proportionate, and their limbs are getting stronger and more developed. The baby’s digestive system is also forming, and they can swallow and process small amounts of nutrition, so he/she can become strong like their mother!

Week 28

Your curled-up baby can now show off his or her new eyelashes to you. At week 28, the baby is beginning to curl up tightly and turn its head down, which is a normal position for babies during birth. Consider a large head of cauliflower nestled deep within your pelvis.

Week 40+

Just keep in mind that babies, like watermelons, come in a variety of shapes and sizes. Your and your partner’s genetic make-up can have a big impact on how big or small your baby is at 40 weeks. There are no good ways to tell how big your baby is before birth, including ultrasound.

The Indian pregnancy month calculator helps women to know their due date based on their menstrual cycle. The website has been very helpful to women all over the world who want to learn and know more about their bodies, but don’t have access to a doctor. The pregnancy month calculator by week can be used to calculate pregnancy in weeks so that women know their due date beforehand. However, it is very rare to find a woman delivering on the very exact date that is predicted by pregnancy week and month calculators. The first trimester, second trimester, and third trimester are also key factors that play an important role during pregnancy or full-term pregnancy. One of the common issues is getting constipated; Know the home remedies to cure constipation during pregnancy. You can read the above contents for more detailed information on different trimester numbers and stages of pregnancy. Your due date may be calculated based on different factors such as your Last Menstrual Period (LMP) or date of conception. You may also be interested in safe periods, checkout for detailed information. There are pregnancy month calculators by week if you want to know after how many weeks is your due date. You can also convert pregnancy weeks to months using the above mentioned simple steps for your convenience. The calculator is designed to be as accurate as possible, but it is only an estimate. Also, know the different trimesters of pregnancy in weeks! It is important to remember that your due date is influenced by many other factors such as family history, ethnicity, stress level, mother’s age, length of time of conception, rate of progesterone rise, and other personal factors. Check out the ways to make your pregnancy easier and healthier at the same time. The calculator does not take into consideration these factors hence it provides just a rough estimate of the date that your baby will be born. This is a great tool to use to keep track of your pregnancy. You can also use this tool to help determine how far along you are.

The next scenario is one that many expectant women are familiar with: If you have a 28-day cycle, you find out you’re pregnant by taking a pregnancy test a few days after your period is late, which means you got pregnant and ovulated about two weeks earlier. So, you must be two weeks along. You learn that you are four weeks along when you visit your doctor to confirm your pregnancy.

However, why did you add two more weeks when you weren’t pregnant four weeks prior, at the time of your previous period? You would think that counting wouldn’t be so challenging.

Confused? Not just you, either. Nobody can predict with absolute certainty when conception will occur, which is the problem with having children. Therefore, health professionals use an international standard to gauge how far along each pregnancy is starting with your LMP, or the first day of your most recent menstruation

Weeks of pregnancy counted

The first day of your last period marks the start of your pregnancy, and counting weeks continues up to Week 40 (when your due date is) and as high as Week 42. The basic equation is LMP + 280 days Equals EDD (estimated due date). Another way to look at it is to say that if you are a week past the start of your last menstruation, you are already pregnant.

But keep in mind that the typical cycle length for this approach, which is 28 days, is just that. If your menstrual cycle is shorter or longer than the average, your due date can alter.

What happens if you’re unable to pinpoint the exact start of your most recent period? The majority of medical practitioners will perform an ultrasound to estimate your baby’s size early in pregnancy, when you are approximately seven to eight weeks pregnant, so don’t panic if you don’t utilise apps or calendars to track your cycle. A “dating” or “viability” ultrasound is what it is called. The size of the embryo helps shorten the embryo’s growth time. It’s not uncommon for this scan to be used as the most accurate gauge of your pregnancy weeks, so don’t be shocked if your doctor instructs you to advance or retreat a week based on the size of your baby.

How to Calculate Weeks of an IVF Pregnancy

If you became pregnant through in vitro fertilisation, the calculation for your pregnancy weeks will look a little different.

Utilizing newly collected eggs: The week after the day your eggs were removed is referred to as Week 2.

Week 2 begins when using frozen embryos, minus the number of days after the embryo transfer. If a 3-day-old embryo is implanted or transferred, for example, on February 12, you’ll be two weeks along by February 9 and can continue to add weeks after that. If a 5-day-old embryo were to be implanted on July 20, week 2 of your pregnancy would have started on July 15.

How to calculate the pregnancy month calculator?

There are numerous techniques to determine your due date. If you know the day you became pregnant, you can calculate your due date by going back 38 weeks. (A human pregnancy lasts, on average, 38 weeks.)

But only the expectant mothers minimum percentage are only aware of their precise conception date. You wouldn’t get pregnant on that day even if you had one sexual encounter within your fertile period, unless you were ovulating. Sperm can endure up to a period of two couple of days inside your fallopian tubes. As a result, it could take up to five days after having sex before you ovulate, at which point a sperm will be ready to fertilise the egg. You ovulate at that point.

So how can a due date be determined without knowing the day of conception?

The last day of your menstrual

The most common way to figure out when you’re due for a pregnancy is to add 40 weeks to the beginning of your last menstrual cycle (LMP). And this is how the majority of healthcare professionals work.

If your menstrual cycle was the normal length, it probably started about two weeks before you found out you were pregnant (28-day cycle). This explains why the average pregnancy lasts 40 weeks as opposed to 38 weeks.

Conception date

If you are aware of the precise date you became pregnant, such as kept track of your ovulation symptoms or if you have used an predictor kit for ovulation, the pregnancy due date using your conception date can be calculated. Simply choose that calculating method from the pulldown option above and enter your date.

Again, it’s not always the case that you become pregnant after having intercourse.

IVF transfer date

The date of the IVF transfer might be used to estimate when you will give birth if you utilised IVF to conceive. If you had a Day 5 embryo transfer, start counting 261 days after that. Count 263 days if you transferred an embryo on Day 3.


In a perfect world, every pregnancy would go according to schedule, but that isn’t always the case. Due dates are guidelines, not rules, and your baby will come when he or she is good and ready, regardless of your due date. Chances are that you’ll deliver within a week of your original due date. Other times, you might go a little early or a little late, depending on your pregnancy. Your doctor may determine that you’ve gained enough weight or have reached a certain alpha-fetoprotein (AFP), a protein made by the baby, that he or she feels is outside the usual range for gestational age. Be prepared for whatever happens!


1. How can I be four weeks pregnant if I am in my fifth week?

Let’s take an example of a baby, when he turns one, it depicts one year of being alive and we call him/her as one year old even though he is in his second year. Similarly, when one week of pregnancy is completed we call it one week of pregnancy, so you will be one week pregnant in your second week and so just depicts the completion of weeks.

2. How accurate is my due date?

The due date is just an estimation of when the baby will be born, usually, babies arrive between 37 to 42 weeks of pregnancy or within one week when the due date is expected.

3. What can an anomaly scan show about my baby?

An anomaly scan or targeted imaging for fetal anomalies scan (4d tiffa scan) is to check if the baby is developing normally or to look where the placenta is lying. TIFFA scan report for a baby boy or TIFFA scan report for a baby girl is the most significant scan in the 2nd trimester as it also makes sure

  •  the internal organs of the baby are developing correctly or not, 
  • checks the blood flow to the uterus, 
  • detects if there are any birth defects in your baby
  • Checks the cervix and measures the birth canal etc

4. What is the length of a full-term pregnancy?

A full-term pregnancy lasts from the beginning of 39 weeks to the conclusion of 40 weeks if you’re carrying a single child. A full-term pregnancy is defined as at least 38 weeks if you’re carrying twins. Based on when your baby is delivered, the American College of Obstetricians and Gynecologists (ACOG) has defined the following terminology during pregnancy:

20 weeks to 37 weeks is considered preterm.

37 weeks (early term) From 0 to 38 weeks six days

Full term: 39 weeks From 0 to 40 weeks and 6 days

41 weeks (late-term) From 0 to 41 weeks and 6 days

After 42 weeks and 0 days, the term ends.

5. Why is your pregnancy determined by your last period?

Why start the clock on childbirth before sperm meets egg (and, in fact, before your ovary ever releases the fated egg that will give birth to your child)? Simply said, the LMP is a more accurate day to track a pregnancy from. Even when you’re a master of cervical mucus and know exactly when you ovulated and when you had intercourse, you’re unlikely to be able to identify the precise time or moment of conception. Because sperm may linger out and wait for an egg to fertilise for three to five days after they come, and an egg can be fertilised for up to 24 hours after it’s been released, there’s a larger window than you might expect.

6. How big is my baby in pregnancy by week?

It’s a lot of fun to watch your baby grow during the nine months of pregnancy. However, it can be difficult to translate all of the inches, centimetres, crown to rump lengths, and so on and so on that determine fetal development. Let us dig into some details:

You may also read:

Happy Pregnancy!

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About alka

Recently reinvented her old love of writing. A Literature graduate from Delhi university had a flair for writing ,and has also written for her college magazines and has also done dialogue writing for college drama.
She later on pursued MBA in Human Resources and Marketing with over 4+ years of experience with international exposure. Has been married for more than 8 years and leads a Blissful life with her husband and a son of 6 yrs

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