4 Weeks Pregnant – What To Expect In Week 4

4 Weeks Pregnant - What To Expect In Week 4

When you’re 4 weeks pregnant, this is the week your period is due … or late!

In this case, you may begin to wonder or even suspect you’re pregnant.

It’s common around this time for women to do a home pregnancy test.

If you’ve already had a positive pregnancy test – congratulations!

4 Weeks Pregnant

It’s normal to feel a combination of excitement and nervousness.

If you’re still waiting for that positive pregnancy test, try not to stress too much.

Be sure to read When To Take A Pregnancy Test If You Might Be Pregnant for more information.

4 Weeks Pregnant Belly

Generally by 4 weeks pregnant, your egg has attached to the inside wall of your uterus.

The egg, now an embryo, is surrounded by fluid in the amniotic sac.

The placenta is still developing, but is sending out tiny hair-like tendrils.

These wrap around the abundant small blood vessels in the lining of your uterus.

Usually, the placenta will completely take over the role of sustaining your baby by 12 weeks gestation.

Under normal circumstances, your blood and the blood of your baby don’t mix.

You both have a separate circulatory system.

The closeness of your blood vessels to those of the placenta allows the exchange of oxygen, nutrients and waste products.

Are You Getting BellyBelly’s Pregnancy Week By Week Updates Emailed To You?
Click HERE to get the FREE weekly updates our fans are RAVING about.

Early Pregnancy Symptoms – 4 Weeks Pregnant

Not all women experience early pregnancy symptoms. Often these are confused with premenstrual symptoms.

Things to look out for are:

  • Bloating. You might experience fluid retention around the beginning of your period.
  • Mood swings. Fluctuating pregnancy hormones are the cause of this and are most noticeable in the first trimester. You might experience moodiness in the week leading up to you period.
  • Cramping. When the fertilised egg implants, it can cause mild cramping, similar to mild menstrual cramps in your lower pelvis or back. Severe cramping should be investigated.
  • Nausea. This can be limited to first thing in the morning, or triggered by a smell or sight. Nausea usually kicks in around 6 weeks when hCG levels rise.
  • Implantation bleeding can happen when the fertilised egg burrows into the uterus lining. A small amount of blood can appear.

Folate In Early Pregnancy

You may have heard it’s important to get enough folate during pregnancy.

Folate helps the neural tube (a structure that forms the brain and spinal cord) to develop properly.

It also helps prevent a major birth defect, spina bifida, from occurring by up to 70%.

During this stage of early pregnancy, your baby’s nervous system is beginning to develop.

A layer of cells fold to form the neural tube. This becomes the baby’s brain and spinal cord.

Above all, at 4 weeks pregnant it’s important to make sure your dietary intake of folate is adequate.

Dietary sources of folate include dark leafy greens, nuts, eggs, meat and chicken.

Here are 9 top foods which contain folate.

Most prenatal vitamin supplements include the synthetic form of folate (folic acid).

The best supplement to take instead is folinic acid, especially if you’ve had problems with fertility, pregnancy complications or miscarriage.

Cigarette Smoke When You’re 4 Weeks Pregnant

All women should quit smoking before becoming pregnant.

If you do smoke cigarettes and become pregnant, certainly now is a good time to quit.

However, while you may not be a smoker, it’s important to know exposure to cigarette smoke has negative effects on the health of pregnant women and their unborn babies.

Second-hand cigarette smoke has thousands of dangerous chemicals.

Exposure to second-hand smoke during pregnancy increases the risk of:

  • Miscarriage
  • Fetal growth restriction
  • Preterm birth
  • Low birth weight.

You can also be exposed to toxins left in places where people frequently smoke. For example on furnishings, paint, clothes, etc.

This type of exposure is third-hand smoke. Usually if a room or item smells like tobacco, it’s likely there are toxins present.

As a result, these toxins can make their way into your bloodstream and your baby’s.

There is research to show third-hand smoke can have very serious effects on your baby’s developing lungs.

Try to minimise your exposure to second and third-hand smoke as much as possible.

4 Weeks Pregnant – Your Baby

Your baby at 4 weeks pregnant is now classed as an embryo.

He or she has made the journey to your uterus, and has embedded in the rich lining of the uterine wall, dividing into two groups of cells.

One group of cells has become the embryo and the other has become the placenta.

The placenta is truly an impressive support system for your baby. Read more in What Is A Placenta? 10 Amazing Placenta Facts.

The heart and circulatory system rapidly form. The neural tube also forms in the first 4-6 weeks of pregnancy and will develop into the brain and spinal cord.

The next six weeks are a critical stage of development for your growing baby.

For example, their organs begin to develop and some organs will even begin to work!

At 4 weeks pregnant your baby is 1mm long and about the size of a poppy seed.

Here are some articles that may be helpful if you’re 4 weeks pregnant:

The TRUTH About Natural Birth
MAXIMISE your chances of getting the birth you want… MINIMISE your chances of
a disappointing or traumatic birth experience. Learn from some of Australia’s
best educators – you’ll feel MORE CONFIDENT heading into birth.
CAN YOU HANDLE THE TRUTH? Click to find out…
Last Updated: January 15, 2019


Kelly Winder is the creator of BellyBelly.com.au, a writer, doula (trained in 2005), and a mother of three awesome children. She's passionate about informing and educating fellow thinking parents and parents-to-be, especially about all the things she wishes she knew before she had her firstborn. Kelly is also passionate about travel, tea, travel, and animal rights and welfare. And travel.

loaded font roboto