How Far Along Am I in Pregnancy?

So, you just took a pregnancy and got a Big Fat Positive (BFP), and you are mixed with all kinds of emotions! I remember it like it was yesterday. I peed on a stick and I instantly got 2 lines. Still, l waited the 3 minutes as instructed in case the other line mysteriously disappeared. It never did! I was pregnant and excited!

The one question that was on my mind was “ok, so how far along am I?”. I literally had no idea. I wasn’t tracking, so I had no idea how many weeks I was. Well, here is a breakdown of how your pregnancy due date is calculated:

***Before implementing any health advice, please check with your doctor first as I am not a medical professional.  Read my full policy for more information.

Gestational Age

All pregnancies are calculated by their gestational age and never calculated by conception date. So what is this? And how is it calculated? The most common way to calculate your baby’s gestational age is by going by the first day of your last period (LMP). That’s when they start counting how far along you are. So basically, they count the 2 weeks before you ovulate and conceive.

If you take a pregnancy test on the first day of your missed period, you are considered 4 weeks pregnant already when you’ve technically been pregnant for 2 weeks. Confusing, I know!!

So why isn’t it calculated by your conception day? Well, no one can really be sure of the exact date they ovulated, the exact date the sperm came into contact with the egg, and the exact date of implantation.

The only people that know this kind of information are the people who conceived through IVF. And even then, they count back 2 weeks to get to the gestational age.

Most people know the first day of their last period, so it is easier to go by this day.

Ovulation Date

If you are an avid tracker and you can pinpoint the rough day you think you ovulated, count back 2 weeks and you have your date!

This is confusing because they constantly talk about conception dates in the movies (probably because they are written by men who have no idea how the whole pregnancy thing works!) but no one ever goes by this date…ever!! Always gestational age!

Every woman is different. Every cycle can be different. You typically ovulate between day 13-15 in your cycle. Once your body releases the egg, the sperm has 24 hours to meet the egg.

Luckily, sperm can live up to 5 days in your uterus and can still penetrate the egg even if you haven’t “done it” on O day!!

Ovulation can occur late too! I ovulated 2 weeks late for one of my pregnancies so when I went in for my appointment, my dates were all wrong. This can happen to anyone. It is very common.

Implantation Date

Another date to consider when calculating the gestational age is the implantation date. This is when you are actually pregnant. Once the sperm has met the egg, it continues its journey from the tube to your uterus. It then attaches to the wall and hCG will be present in your body.

This journey can take 7-12 days (source). That’s quite a range!

Signs such as spotting and cramping can indicate this date. Otherwise, there is no way of knowing when this actually happened.

If you ovulate a few days late and your implantation takes the full 12 days, your dates may be off as well. That’s why it is always best to wait until you see your OB or midwife for more accurate dating.

Measurements Through Early Ultrasound

This is the best way of knowing how far along you actually are. Going by your last period is great if you have regular cycles that are around 28 days long. If you have irregular or longer cycles, it is hard to gauge how far along you are.

For example, if your cycles are 35 days, your gestational age maybe a week behind your LMP date. This happened to me. I went to my 8-week appointment and was informed that I was in fact, only 7 weeks as my cycles this time were around 35 days.

Dating through ultrasounds are more accurate during the early stages of your pregnancy (8-12 weeks). After that, they become more difficult as this is where measurements differ from baby to baby.

Pregnancy dates can be super confusing and complicated. You will find out your true dates when you have your first ultrasound or sonogram. Until then, hopefully this gives you some idea of how far along you are.

Congrats on your BFP and welcome to the world of motherhood!