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Now a pregnancy test can maybe reveal if you are pregnant or not. Nervous? You’re not alone!

It can be too early to tell too.

Even if you still haven’t tested positive, you may notice other early signs of pregnancy.

Inside your body, your baby may be is implanting in your uterus, and you are really pregnant! A special time for sure!

This article will cover fetal development, how big your baby is, pregnancy symptoms, and what’s happening with your body, mom.

Week 3 | Week 5

4 weeks pregnant info

What to Expect When 4 Weeks Pregnant

Your Baby’s Development

embryo at 4 weeks pregnantThe fetal age of your baby is now 2 weeks. You can rejoice in the fact that your new little one has graduated to an embryo this week!

It will consist of two layers of cells, the epiblast, and the hypoblast, that will, later on, develop into the essential organs and body parts that your baby requires to function on their own.

At some point this week, implantation occurs. The average day for this to happen is 9 days after ovulation.

This week is a busy time as the amnion and the yolk sac are also maturing for your baby’s use. The amnion is filled with amniotic fluid that surrounds and protects your new little embryo, while the yolk sac produces the blood and nourishes it until the placenta is able to take over this very important role of development.

implantation 4 weeks pregnantEven though a lot is going on and the embryo is developing very quickly, your baby-to-be is only the size of a poppy seed at the present, so there is not a whole lot to see with the naked eye from the outside.

There will be plenty of time for you to grow and see for yourself exactly how much space your new addition is going to require. If you are one of the lucky ones to have a multiple-pregnancy in the works, you are sure to see the signs of growth sooner than you can imagine since there is 1 (or 2!) more to nourish and grow during this time.

Here is a good basal thermometer if you want to give charting a try (and you’re not yet confirmed to be pregnant).

The endometrium is a crucial point for your egg since it uses it as a means for nutrition and for taking away waste material during development.

The implantation site, where your egg attaches to the uterine wall, will eventually develop into the placenta that is essential for your baby’s development for pregnancy. During this time, your body produces the hormone hCG (human chorionic gonadotropin) that will let your body know to stop releasing eggs and to begin the production of estrogen and progesterone. With the increasing levels of hCG, you may even be able to show a positive result on a pregnancy test at this point in time.

Mom’s Body When 4 Weeks Pregnant

4 weeks pregnantWhen you are 4 weeks pregnant, you might receive a positive pregnancy test result. However, many women will have to wait a few more days.

If your embryo implanted late, it may take a few more days or even a week before your hCG levels have risen enough to make the test come out positive.

If your pregnancy test has come back positive then you will want to make an appointment with your medical practitioner as soon as possible.

Typically, your first prenatal appointment will happen around 8 weeks of pregnancy unless you have experienced previous problems with pregnancies or in a high-risk category.

During your first visit is a good time to go over any medications that you currently take, or may take occasionally since there can be many over the counter medications that are not recommended for pregnant or nursing mothers.

Possible Early Pregnancy Symptoms

Some women will experience slight cramping and even spotting during this week and can mistake these early pregnancy symptoms for the beginning of their monthly period.

Others will have no indication of the implantation that has taken place and will still continue to wait with anticipation of a positive result from a pregnancy test.

Mothers of multiples will have a tendency to have stronger symptoms due to their bodies working overtime on producing hormones essential for the development of the new little ones.

Extreme nausea, fatigue, and even breast soreness are hard to ignore for those who are carrying more than one embryo during this time.

Sleep is crucial for expecting mothers no matter what age or where they are in their gestation period. Be sure to not only get all the vitamins and nutrients needed for your developing baby but also get enough rest as your body is working extremely hard to prepare the groundwork for your little one who will rely on you for all of its needs in the coming months.

Week 4 Video

Diary of a Daughter

What’s it really like being 4 weeks pregnant…? Here’s a true diary from a 4 weeks pregnant mom (Me..!)

No signs of menstruation. BBT is staying high and increasing. This is so exciting. But also so scary to start hoping again. I’m only a few days from a pregnancy test now.

Are you also 4 weeks pregnant? Let’s create a pregnancy diary together! Please share your experiences and thoughts by leaving a comment below!

More About Early Pregnancy


Mayo Clinic, Mayo Clinic Guide to a Healthy Pregnancy
Joanne Stone MD and Keith Eddleman MD, The Pregnancy Bible: Your Complete Guide to Pregnancy and Early Parenthood
Nilsson, L; Hamberger, L. A Child Is Born
Soderberg, L., Mammapraktika. B Wahlstroms.

Image: Image of 4 weeks embryo thanks to the Science Museum

Week 3 | Week 5

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