How Far Along Am I? Calculating Weeks Pregnant

You have a suspicion something is happening with your body. Could you be pregnant?

You start thinking about your menstrual cycle and you count the days, trying to figure out dates.

You buy yourself a pregnancy test to find out whether it could be true.

As you place the pregnancy test in your urine and wait for the result, your heart races.

This is it. The moment you find out.

Either you were going crazy, or that intuition of yours was working all along.

Then you see it: two lines!

Yes, you can distinctly see more than one line.

You’re pregnant!

As a multitude of emotions erupts inside you, your mind quickly shifts to the question: How far along am I?

How far along am I by due date?

When calculating an estimated due date, calculators and tools count from the first day of your last menstrual period.

Do you know when the first day of your last period was? That was day one of week one.

By the time you find out you’re pregnant, which is when your next period would have been due, you’re considered four weeks pregnant – even though you’ve technically only been pregnant for about two of those weeks.

Pregnancy lasts for an average of 40 weeks. In fact, research has shown pregnancy length can vary by up to five weeks. However, 37 to 42 weeks is considered a full-term pregnancy.

That’s why, when you’ve worked out your estimated due date, you should remember it’s exactly that – an estimated date.

Around 40% of babies are born before the estimated due date, and around 40% are born in the two weeks after.

You might like to read 40 Reasons To Give Your Baby 40+ Weeks Of Pregnancy.

Only 3-5% of babies are born on their actual estimated due date.

What if I don’t know the date of my last period?

It’s easy to keep track of an average 28-day cycle. You might have irregular cycles, though, or you might not remember or know what the first day of your last menstrual period (LMP) was.

If you don’t know the first day of your LMP, your doctor might offer you an ultrasound to see how far along you are.

An internal ultrasound is used for very early pregnancy, because the baby is usually too small to be seen clearly if the scan is done via your abdomen.

A gestational sac is usually visible and, from around six weeks of pregnancy, you might be able to see the first flutters of your baby’s heartbeat.

You can find out more in When Can You See Baby’s Heartbeat On Ultrasound?

If you know the date of your last period, you can use BellyBelly’s due date calculator tool, so you can work out your baby’s estimated due date.

It’s the same calculation method your healthcare provider will use, with an additional option to include your ovulation date (if known). This can make your estimated due date even more accurate.

Remember, though, babies come whenever they are ready.

To calculate your estimated due date, see BellyBelly’s due date calculator.

How far along am I from ovulation date?

Even if you don’t have a regular average cycle, or your cycle length varies, the second half of your cycle is the more regular part.

The second half goes from ovulation to the first day of your next period, or missed period if you’re pregnant.

That means any pregnancy calculator will say you’re two weeks pregnant when your egg and the sperm haven’t even met yet.

The reason it’s done this way is because the first day of your period is the first day of your menstrual cycle and the due date is calculated by adding 280 days or 40 weeks to this date. Remember, the average pregnancy is 40 weeks long.

Technically, if we count pregnancy weeks from ovulation you’re two weeks less pregnant than what the due date calculator says by starting from your LMP.

How far along am I by conception date?

Knowing your conception date is one of the most important pregnancy milestones. But not all women are able to identify the day they conceived.

Conception will always occur after the egg is released from the ovary. The egg’s life span is quite short and it’s viable for just 24 hours. That means conception can happen from a few minutes after ovulation up to a day after.

As conception happens so close to ovulation, the estimated due date won’t be much different from the one that’s calculated from ovulation date.

How far along am I by IVF?

With assisted fertility like IVF, conception occurs outside the woman’s body. That means the day the embryo is inserted into the uterus is known as implantation day.

When a woman is having IVF treatment, the date of conception is obviously known, and many tests are done to make sure implantation occurs at the optimal time of the woman’s cycle.

Although IVF isn’t a natural method to conceive, the natural conception process should be mirrored as much as possible.

After conceiving via IVF, you should count your pregnancy weeks in the same way as you’d count them from conception date.

For more information about IVF be sure to check out IVF – Find Out How It Works In This Cool Video.

How do I know how many weeks pregnant I am?

Once you’ve used any of the pregnancy tools available to calculate your due date it will also let you know how many weeks pregnant you are at any given time.

These calculating methods have been designed to provide you with your present gestational age.

They are also very handy in reminding you about a number of pregnancy milestones – such as blood tests, ultrasounds, trimesters, or appointments with your midwife or doctor.

The first time you’re told your estimate due date you’ll also be told exactly how many weeks pregnant you are at that moment.

You’ll know the day of the week your pregnancy week changes too. For example, it could be on Wednesday, so you will add an extra number each Wednesday until your baby is born.

How far along am I in my pregnancy symptoms?

Pregnancy symptoms are a bit more difficult to go by as they depend on many different factors. Symptoms even vary for the same woman who goes through more than one pregnancy.

We have expectations that some symptoms are more likely, depending on which trimester you’re in.

Even so, it’s very difficult to estimate the length of a pregnancy by the symptoms you’re experiencing.

Be sure to read Pregnancy Symptoms Week By Week for a thorough outline of the types of symptoms you might experience as you progress through your pregnancy.