How To Calculate How Far Along You Are

To calculate how many weeks pregnant you are, you count from the first day of your last period. Why? Well, because pregnancy weeks are actually measured according to your reproductive cycle, not the age of your unborn baby.

The cycle begins when your body flushes out your uterus to make it hospitable for a fertilized egg. This is the first day of your cycle when you start bleeding, and, if you conceive, that is the first day of your pregnancy.

Over the next 10 days your uterus will grow a new lining, your overies will release one or more eggs, and sperm will come into contact with and fertilize an egg. 8-10 days later that tiny new person will have grown and developed to the point that it can embed in the wall of your uterus, causing a hormone spike in your body.

Here is a due date calculator that you can use to find your ESTIMATED due date. Take note  that it’s an estimate – since there’s a 5 week window for healthy birth, the due date is more like a general guess to give you an idea of when to be ready. Babies run on their own time, though!


How Early Can I Get A Positive Test


Within a few days of implantation there will be detectable levels of HCG (the pregnancy hormone) in your blood and urine. However, most over the counter pregnancy tests cannot detect the trace amounts yet. If you buy a 5 day early test you should be able to detect those traces around the 23rd or 24th day since the first day of your last period, depending on how long your body typically takes to get from the first day of one period to the first day of your next period.

However, those early tests are a little bit unpredictable, and at the earliest possible date they can be up to 50% inaccurate, so it’s best to wait until your next period is due, and then use a test made for early detection. If you are already late for your period, a standard pregnancy test should be fairly accurate.

There have been cases, though, of healthy pregnancies not showing up on an over the counter test until several months in! It’s an anomaly and very uncommon, but it has happened.


How Do I Convert Weeks To Months Pregnant

There isn’t a super simple way to convert your number of weeks pregnant into number of months pregnant, other than to use a graph. The easiest way to determine how many months pregnant you are is to calculate your due date, then count months by that day. Ex: Due date August 15th means that one July 15th you are 8 months pregnant, on June 15th you are 7 months pregnant, and etc.

Here’s a table for you to check:

Weeks 1-4 = First month. At the end of your fourth week you are 1 month pregnant.

Weeks 5-8 = Second month. At the end of your 8th week you are 2 months pregnant.

Weeks 9-13 = Third Month. At the end of your 13th week you are 3 months pregnant

Weeks 14-17 = Fourth Month. At the end of you 17th week you are 4 months pregnant

Weeks 18-22 = Fifth Month. At  the end of your 22nd week you are 5 months pregnant.

Weeks 23-27 = Sixth Month. At the end of your 27th week you are 6 months pregnant.

Weeks 28-31 = Seventh Month. At the end of your 31st week you are 7 months pregnant.

Weeks 32-35= Eighth Month. At the end of your 35th week  you are 8 months pregnant.

Weeks 36-39 = Ninth month. On the last day of your 39th week you reach 9 months pregnant.

Weeks 40-43 = Tenth Month. On the last day of your 43rd week you reach 10 months pregnant.

WHY DID I ADD A TENTH MONTH??? Because, while the 43rd week is high risk and generally avoided by the medical community, it is not unheard of for moms to birth in their 43rd week if no medical intervention is done. Anything up to 42 weeks is healthy and normal, so it is safe and fine to be 9.5 months pregnant!


When Does My First Trimester End

There are differing opinions on trimester divisions, but what seems to be the going normal for when your first trimester ends is at the end of your 13th week. Meaning your second trimester begins with your 14th week. The third trimester begins at week 26 and can last until week 42 or 43.

The trimesters are divided into groups of 12-14 weeks. The reason the third trimester covers weeks 41, 42, and 43 is because 40 weeks is when baby is statistically fully physically ready for birth.

Weeks 1-13 = First Trimester. This feels the fastest since we don’t test until weeks 4 or 5.

Weeks 14-26 = Second Trimester. This is when you are likely to feel the best. Optimize these weeks by getting into a routine of fitness and healthy eating so that it will carry over into your later months!

Weeks 27-42 = Third Trimester. While many apps and sites will tell you baby is fully developed by week 36 and perfectly healthy to birth by 38, there are many, many studies showing that 40-41 weeks is the healthiest stage for your baby to be born! Be patient with this long last trimester!  Baby will be here soon! Go the full forty! 


How Many Weeks and Months is  A Healthy Pregnancy

With no induction methods used, a little over 50% of babies are born between 39 wks and 40 wks + 6 days. Any birth before the beginning of week 37 is considered premature, and any birth after 42 weeks  is considered post term.


That means that there is a five week window (from 37 to 42 weeks) where baby can decide

that it’s time to be born! It’s best to be ready for baby by that 37th week, but to not get your hopes up until the 41 week mark!

It’s well documented that it’s better to go a week past your 40 week mark than it is to go a week before, so don’t get too anxious!  If you start getting antsy as that deceptive “due date” approaches, check out the Go The Full 40 website for some calming advice and reminders!


I hope this has been helpful! What’s your favorite tool for due date calculating? What’s your favorite pregnancy progress tracking application? Post a comment and let us know!





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