4 weeks pregnant – Placenta and embryo begin forming

Although a fertilised egg may have implanted in your womb just two weeks ago, you are officially four weeks pregnant! It happens because pregnancies are measured from the first day of your last period rather than the day you actually conceived your baby.

How Many Months is 4 weeks pregnant?

There are 40 weeks in a pregnancy, starting from the first day of your last menstrual period. If you are 4 weeks pregnant, you are in month 1 of your pregnancy. Only 8 months more to go!

If you have more questions and want to know more about weeks, trimesters, months and due date during pregnancy you can visit our post about how to calculate pregnancy.

Your baby at 4 weeks pregnant

For the first 8 weeks of pregnancy your baby will be known as an embryo. The baby may be minuscule but big things are happening! At this stage, the embryo has three layers:

  1. The inner layer (endoderm) which will become the lungs, liver, digestive system and pancreas.
  2. The middle layer (mesoderm) which eventually develop into the skeleton, muscles, kidneys, blood vessels and heart.
  3. The outer layer (ectoderm) which will form the nervous system, teeth and skin.

The tiny baby inside you is about the size of a poppy seed (1-2 millimeter) and is growing rapidly in your womb.

4 weeks pregnancy baby size

In addition, the embryo is protected by an amniotic sac, which is filled with cushioning fluid, and attached to a tiny yolk sac that provides all the nourishment it needs. The outer layer will later develop into the placenta and provide your baby with oxygen and nutrients.

Your body at 4 weeks pregnant

Conception usually takes place about 2 weeks after your last period, around the time you release an egg. Most women begin to feel symptoms around the week 5 or 6 of pregnancy. Therefore, if you think you could be pregnant but haven’t noticed any symptoms, you still might be.

However, you may start feeling that something is different in your body. The first thing most women notice is that their period doesn’t arrive and you may stat feeling very early physical symptoms:

  • Changes in your breast, including soreness and discomfort
  • You may develop cravings for some foods
  • Notice that your favourite foods and drinks are suddenly unappetising
  • You may feel exhausted and weepy
  • Mood swings

Other important early symptom of pregnancy is noticing some very light bleeding, or ‘spotting’, known as implantation bleeding. Implantation bleeding usually happens about 10 days after ovulation when the fertilized egg attaches to the interior lining of the uterus and often happens around the time your period would have been due.

It is important to know that if you notice any bleeding at any stage of your pregnancy, it should be checked out by your doctor or midwife

Within 6 to 12 days after fertilization, the egg starts to release human chorionic gonadotropin (hCG) and by the time you are 4 weeks pregnant, you can usually get a clear positive on a urine pregnancy test. hCG is largely responsible for the nausea, or “morning sickness” that many women experience in the first trimester.

Can I find out the baby’s gender at week 4 of pregnancy?

Although your baby’s gender is determined at the moment of fertilization, you won’t know if you are having a baby boy or girl at week 4 of pregnancy and you will have to wait until your week 20 ultrasound.

Find out what to expect next week or any other week!

Images: Designed by Freepik and modified by Bescienced

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