pregnancy week 3

Pregnancy Guide: Week 3

Congratulations! You’re pregnant, although you still may not know it. You’ll likely know next week. At this point, it’s just a cluster of cells, but it’s growing rapidly. Your fertilised egg won’t reach your uterus for another four days, and then it takes two or three more days for implantation to happen. While you don’t know yet whether it’s a boy or a girl, and you won’t until about 17 weeks, the gender has already been determined.

3 weeks pregnant is how many months?

You’re still in the first month, but you’re almost a full month pregnant now. Soon, you’ll only have eight more months to go. Enjoy the ride—you’re just getting started.

Your Baby at 3 Weeks

The blastocyst is tiny now. That’s probably not what you’ll choose to name him (or her) eventually, but that’s what he (or she) is called right now. This itty-bitty mass of cells will travel all the way up through your fallopian tube, to your uterus, in a matter of days—making it a small, mighty warrior.

While you don’t know whether it’s a boy or a girl, the gender is already assigned and will begin to develop accordingly. Your fertilised egg has 46 chromosomes, just like you and Dad, and almost every other human on the planet. That means that your X contribution and Dad’s X or Y contribution have already been established. 

If “Blastocyst” gets a Y from Dad, it’s a boy!

How big is a baby at 3 weeks?

Right now, your baby is the size of a pinhead. It’s only 0.0048 millimetres long and weighs so little it’s hardly worth recording. What you feel now isn’t attributed to the baby’s size or weight, but rather the toll it’s taking on your energy and hormones.

Your Body at 3 Weeks

You’re finally pregnant. The first two weeks were full of prep and now you’re on to the next phase of your journey. It only takes a few hours after conception for your egg to start dividing into cells. After about seventy-two hours, your zygote will have multiplied into 16 cells—isn’t it phenomenal? 

This ball of cells is called a morula. Your morula will continue to travel down the fallopian tube, dividing into almost one hundred cells. This cluster of cells is called a blastocyst. 

Once it reaches the uterus and latches on, it will continue to develop into an embryo, then a fetus, and then a baby. The blastocyst at this point already has two cell types. The outer layer of cells are trophoblasts and the inner will become the placenta. 

The embryoblast cells are on the inside and are what will eventually become your baby.

pregnancy week 3


If you’re starting to feel some abdominal pressure or cramping, that’s normal right now. It’s a sign that things are going right. These mild cramps (without blood) are generally a sign that the embryo is implanting. It could also come from thickening of your uterine lining, where the increased blood flow is going to your uterus, or your uterus is simply growing to make room.

One of the most bizarre symptoms of pregnancy at this stage is a metallic taste in your mouth. It may feel like you just shoved a bunch of pennies in your mouth, but that comes from hormones. There are so many different hormones in your body that you’re not used to right now, and that can cause your taste buds to go haywire.

If you can’t stand the taste, eat sour candy, drink lemonade or eat food marinated in vinegar. You could also try brushing your tongue when you brush your teeth or gargle with salt water.

Tips/Things to do

If you do already know you’re pregnant, it’s even more critical to ensure you’re doing the things you need to be doing to keep you and your baby healthy—and avoiding the things that could be damaging.

Increase your iron intake. By combining foods that are rich in iron with foods that are rich in vitamin C can help your body absorb more iron, which helps support increased blood flow and volume. 

  • Try putting berries in your cereal or yogurt, 
  • eat mango, kiwi, strawberries, tomatoes, bell peppers, or asparagus, 
  • eat meat, like beef and poultry, which also has a lot of iron.

Calcium supports strong bone development. Eating foods that are rich in calcium will assist with your baby’s growth. If you don’t have a high enough calcium intake during pregnancy, you’ll find your baby taking it from your bones. 

  • You should get four servings per day or at least 1000 milligrams of calcium.
  • Mix it up with milk, frozen yogurt, cereal, cheese, or calcium-fortified juices.

Eat healthily at restaurants. You may be tempted to indulge when you eat out, but you can still eat plenty of delicious foods while staying healthy. 

  • If you’re eating Japanese, steer clear of raw options and go for teriyaki chicken or fish, soba-noodles, or edamame. 
  • Order lean beef or chicken at Italian restaurants. 
  • Eat fajitas at the Mexican place.
  • Order anything that’s not fried if you’re going for Indian food.

Even if you don’t know you’re pregnant, hold off on colouring your hair. During the first trimester, it’s best to avoid those chemicals on your skin and in your body. After the first trimester, you can do some highlights or touch up your scalp. 

Keep in mind that your raging hormones will affect your hair and make it react differently to the colour, too.

Get plenty of fluids to replace what you’re losing if you have nausea during pregnancy. Drinking plenty of water can also help alleviate your cramping and other painful symptoms. Rest and water are important at this stage, and if you find you can’t stomach much, try popsicles, clear broth, or hot water with lemon. 

Add solids back in slowly and listen to your body.

Keep taking those tests. Pregnancy tests are faster and more accurate than they used to be, so if this one is negative, you can try again in a few days. If you are pregnant, it won’t be long before the test shows it.

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