Twenty weeks (or 140 days) is halfway through pregnancy. The tricky part is figuring out when you’re 20 weeks along!
Don’t worry; I’ll help you determine your 20-week gestational period so you can plan each stage of your pregnancy journey.
How Many Weeks Is Halfway Through Pregnancy?
Pregnancy lasts for 40 weeks or 280 days. 20 weeks is halfway through pregnancy (or 140 days).
It’s an emotional (pregnancy hormones), physical (hello, morning sickness ? and breast tenderness!), and mental journey that you’re on for nine months.
But how do all those weeks translate into how many weeks pregnant you are?
You need to know exactly how many weeks you are pregnant to figure out how many weeks you are halfway through!
How Far Along Am I? (In Weeks)
There are two ways to figure out how far along you are:
- Knowing your conception date.
- Knowing the first day of your last period.
1. Your Conception Date
If you track your ovulation, then you can estimate when conception happened. If you don’t know when you ovulated, skip to option 2: the first day of your last period.
On ovulation day, your egg is 14 days (or two weeks) old.
Imagine today is January 29:
- You ovulated on January 16.
- Your egg began to mature two weeks before ovulation: January 2.
- The difference between January 29 and January 2 is 27 days.
- Use this calculator if you’re terrible at subtracting dates like I am.
Divide your egg’s age (27 days) by seven (7 days a week)= 3.9. You are 3.9 weeks pregnant!
Conception Date Formula:
For my math people, to find weeks pregnant:
(Today’s Date – Age of the Egg) ➗7= Weeks Pregnant
2. The First Day Of Your Last Period
You can calculate how far along you are based on your last menstrual period. It won’t be as accurate as knowing your ovulation date, but it should be close if you have regular cycles.
- Start with today’s date. Example: July 8.
- Subtract the days since the first day of your last period. Example: May 23. Use a calculator if you’re having trouble counting. In this case, there are 46 days between the two dates.
- Divide the days by seven (7 days in a week).
In this example, you are 6.6 weeks pregnant.
First Day of Last Period Formula:
(Days between today’s date and the first day of your last period) ➗7= Weeks Pregnant
If you don’t know when you ovulated, when your last menstrual period was, or have irregular periods, your doctor will give you an estimated due date (EDD) using any information that you can provide to them at your first prenatal appointment.
Then, at your first ultrasound (between 8 and 12 weeks), your doctor will measure your baby and give you a more accurate due date based on those measurements.
Usually, if the ultrasound date is within five days of your EDD, they keep your EDD. If your ultrasound shows a bigger difference, they will go with what it says.
How Do I Calculate My Due Date?
You can use a pregnancy calculator (like this pregnancy due date calculator from the Mayo Clinic) to estimate your due date, but if you want to figure it out yourself, here’s how:
- Conception Date: Add 266 days. For example, if you know you ovulated on February 14, your due date is May 19 (February 14 + 266 days).
- First Day of Last Period: Start with the first day of your last period and add 280 days. For example, if your period started on November 17, your due date is August 24 (November 17 + 280 days).
Use this chart to calculate your due date based on your day of conception.
20 Weeks Pregnant Milestones
Now that you’ve reached the second half of your pregnancy, you and your baby can expect a few milestones.
- Learning the Sex of Your Baby: Some couples will find out the sex of their baby through blood tests as early as eight weeks, but most will find out at their 20-week ultrasound (also called the anatomy scan).
- Size: Your baby’s body is about 20 inches long and weighs just over a pound. They are about the size of a large grapefruit.
- Skin: Your baby’s skin is thin and transparent but will become thicker and more opaque as it develops.
- Eyes: They can open and close their eyes and may even be able to track light or moving objects.
- Bones: Your baby’s bones are starting to solidify.
- Feeling Movement: One of the most exciting things in the second semester is feeling the baby move. You might feel quickening (like butterflies, flutters, or popcorn popping) between 14-15 weeks. First-time mothers typically feel more movement between 16 and 20 weeks.
- Starting to Show: Your belly will “pop” between 12 and 20 weeks later.
Preparing for Baby at 20 Weeks
Now that you’ve reached the halfway point in your pregnancy, you can start thinking about your due date and what things you should prepare before your baby arrives.
- Pack a hospital bag (here are all the clothes you need for the hospital postpartum).
- Make a postpartum survival kit.
- Create a birth plan and prepare for labor – what will be helpful during labor and delivery, such as snacks or music that can soothe your nerves and relieve pain.
- Plan your baby shower – set a guest list, pick a venue, plan games like a diaper raffle and prizes, etc.
- Create your baby registry.
- Order your breast pump.
- And if you’re like me, you will still need to create a list of baby names ?!