Pregnancy Week By Week

What to Expect in Week 4 of Your Pregnancy

Fourth Week of Pregnancy: Week by Week

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Your little one has made itself cozy in your uterus and has implanted. This is a key step to pregnancy and means that your little one has found it’s home for the next 8 months.


What to expect in your 4th week of pregnancy: Signs & Symptoms

Some exciting things are taking place inside your body, although you may not even realize it at this point. Your baby has implanted into your uterus, which will be its home until it is born. This implantation may be associated with cramping at 4 weeks pregnant. This cramping may be a result of the baby literally implanting into the uterus lining.  

Once implantation occurs, your body is triggered to think that it is pregnant and certain hormones are released. One of these hormones, HSG, is released in enough quantity that is detectable on a home pregnancy test at this stage. Therefore, now is the week that you can see those two pink lines, assuming you have normal cycles.

You may experience some mild symptoms that are very similar to PMS symptoms. From bloating to mood swings, those pesky hormones play a role in our bodies whether we are pregnant or not.

You may notice slight bleeding that is not as heavy as a period bleed by any means. Some women will experience implantation bleeding, which is a little blood that presents when the embryo implants into the uterus. Implantation bleeding should not be a cause for concern and is totally normal. You may also notice some pressure which may feel like cramps. Of course, if you are concerns about anything that is going on in your body, call your health care provider.

The most obvious symptom of pregnancy at this stage is a missed period. If you missed your period and had intercourse around the time of ovulation, there may be a good change that you have a baby on board.

Your Baby’s Development

Your baby has implanted into your uterus, the space where it will be growing and developing for the next 8 months. A placenta is starting to develop at this point as well. Baby is itty bitty and has not formed recognizable body parts yet.

Belly Size At 4 Weeks Pregnant

Your belly will not be noticeably any bigger during your 4th week of pregnancy. Many women don’t even know they are pregnant yet, and your belly will look just as it did before you became pregnant.


Take a home pregnancy test.

Continue to take your prenatal vitamins

Call your doctor to make a prenatal appointment. While most doctors will wait to see a pregnant woman until a little later in her pregnancy, it is a good idea to get something on the books.

If you are feeling well and tolerating all foods right now, make sure to load up on veggies and nutritious foods like low-mercury fish and shellfish 2 times a week. You may not be able to stomach anything but plain crackers and ginger ale in a few weeks so take advantage of your appetite while you feel like eating.

Embrace naptime. Even this early in your pregnancy you may feel tired. You must prioritize your health through this entire journey, so if your body needs a nap, take that nap!

Shopping List

If you have had a positive pregnancy test, you may want to keep it in a keepsake box

Invest in a pregnancy journal to document your journey

 Look at the ingredients in your personal care products and swap out choices that have questionable ingredients like phtalates. Some great brands include (?—I personally use Honest company products but I am not partial to any brand).


This article is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.

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Lauren Manaker About Author

Lauren Manaker is an award-winning registered dietitian, certified lactation counselor, and book author. She sits on the executive committee of the Women's Health Dietetic Practice Group of the Academy of Nutrition and Dietetics and is on the Breastfeeding Advocacy committee. Lauren is an infertility survivor, mom-of-one, rescue pup lover, and wife to a very lively husband. She lives in Charleston, SC.