4 Weeks Pregnant | Symptoms and Your Baby

4 Weeks Pregnant | Symptoms and Your Baby

4 Weeks Pregnant

At 4 weeks pregnant, this is the week your period is due or even late.

You may begin to suspect you are pregnant and experience some symptoms of early pregnancy.

When you’re 4 weeks pregnant, your egg is now well attached to the inside wall of your uterus and has become an embryo.

The placenta is still developing, but it is sending out tiny little hair-like tendrils, which wrap around the abundant small blood vessels in the lining of your uterus.

In normal circumstances, your blood and the blood of your baby do not mix. You both have a separate circulatory system. Exchange of oxygen, nutrients and waste products is made possible due to the closeness of your blood vessels to the blood vessels of the placenta.

The next 6 weeks are a critical stage of development for your baby, as their organs begin to develop and some will begin to function. You may not be a smoker, but exposure to cigarette smoke has been linked with increased risk of miscarriage. It’s important to be mindful of this and do everything that you can to support the healthy development of your baby. BellyBelly has a fantastic, supportive article on smoking during pregnancy and how to quit.

If you have an indoor cat, it’s best to avoid changing kitty litter due to a parasite that can be found in some cats’ feces. This parasite causes toxoplasmosis and can cause serious health problems for your baby.

4 Weeks Pregnant – Your Body

You may have heard that it’s important to get enough folate during pregnancy. This is in order to help the neural tube develop properly, as well as prevent a major birth defect, spina bifida, from occurring by up to 70%.

Most pregnancy supplements include the synthetic form of folate (folic acid). Dietary sources include dark leafy greens, fruits, nuts, eggs, meat and chicken and grains. Spinach, yeast and asparagus have some of the highest levels of folate.

However, it’s important to note that 1 in 4 people will have problems converting synthetic folate in the body.

A MTHFR gene mutation affects 1 in 4 people seriously and 1 in 2 mildly. One form of the mutation results in a 40% to 60% decreased ability to produce the body’s most active form of folate. The best supplement to take instead of folate is folinic acid, especially if you’ve had problems with fertility, pregnancy complications or miscarriage. A simple test for MTHFR may give you some answers, so don’t hesitate to ask your doctor. Find out more about MTHFR and how to find the right supplements.

4 Weeks Pregnant – Your Baby

At 4 weeks pregnant, your baby 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 our article, 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.

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

4 Weeks Pregnant – Symptoms

According to BellyBelly forum members, here are some symptoms they experienced when 4 weeks pregnant. Please note that everyone is different and you may have some, all or none of these at this stage of pregnancy:

  • Nausea
  • Heartburn
  • Frequent trips to the loo
  • Constipation
  • Occasional backache / lower backache
  • Extreme fatigue
  • Hot flashes
  • Shortness of breath
  • Over emotional (lots of crying!!)
  • Sore breasts/sore nipples
  • Light headed
  • Sensitivity to smells
  • Things taste “different”
  • Feeling completely normal

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

Are you 4 weeks pregnant? Share your thoughts and experiences in the comments section below.

Last Updated: August 14, 2015


Kelly Winder is the creator of BellyBelly.com.au, a doula, writer and mother to three awesome children. Currently, she's travelling the world for 12 months with her partner and children, and hopes to inspire more families to do the same. Visit aroundtheworldpluskids.com.au for more information.