Track your pregnancy week-by-week

Pregnancy week by week

5 Weeks Pregnant

Length of baby: 0.33cm (3.3mm)
At about 0.33cm, your baby, though small, is already starting to form major organs like it’s heart, liver, kidney and stomach.


Week 5 is probably the time you find out that you’re pregnant. Well as you know, this is because you have missed your period, and you start think to yourself……… could….. this….. be? Let’s take a pregnancy test!

There could also be symptoms which are afflicting you, like sore breasts, fatigue and nausea. The same pregnancy hormones which gave you a positive result are the ones responsible for all your symptoms.

This truly is the start of your journey.



How big is baby at 5 weeks? Your baby at week 5 is the size of a sesame seed, which is about 3.3mm (0.33cm) big.



You are still in your first trimester, so you do not need to gain much weight. By the end of the first trimester (week 12), you should be expected to gain anywhere between 0.5kg to 2kg. 



At this stage, your body is beginning to undergo the changes to prepare it to carry your baby for 9 months.

Many mothers say the first trimester is usually the toughest to get through, so don’t fret! It’s in fact good to go through the toughest part first, because it will only get easier from here on.

If you are thinking of what to expect at being 5 weeks pregnant, here are some signs and symptom that your body might be experiencing:

  • Morning Sickness. Oh boy, the most dreadful symptom of pregnancy. The nausea and queasiness which strike you, often at times when you least expect it, is here. Morning sickness can strike you at any time of the day, and unfortunately some mothers will feel nauseous the entire day. What you can and should do is to experiment with different strategies to deal with the nausea. Some find comfort food, others try sweets. Some also find that eating small meals many times a day helps.
  • Fatigue. You find that you are easily tired and want to take naps everywhere you go, even in the middle of the day. Your body is drained from preparing a safe and comfortable home for your growing baby, and you should indeed get the extra rest. Do remember to eat every few hours so you keep your blood sugar level (and energy) up.
  • Cramps. Cramping could be a sign that your embryo is being implanted nicely into the lining of your uterus. It could also be a sign that your uterus is beginning to expand. However if you experience severe cramping (which you shouldn’t), do consult with a doctor immediately.
  • Sore Breasts. Your boobs are aching, and that is perfectly normal. In fact, this is the most common symptom at week 5 as your breasts are getting ready for milk production.
  • Frequent Urination. At week 5 of pregnancy, your kidneys are expanding, so you will find the urge to look for the toilet more often. However don’t restrict your water intake lest you get dehydrated.

Some women are lucky in that they do not experience any symptoms. Do not think that there is something wrong with the pregnancy just because you do not experience the morning sickness. But what you can do is to thank the lucky stars!


Many mothers say the pregnancy symptoms are toughest to get through during the first trimester.



At 5 weeks, you look far from pregnant. 

However you might start to feel bloated and also be conscious of your weight gain. Whatever you do, do not starve yourself because your baby will need all the nutrients it can get.

Putting on weight during pregnancy is not only normal, it is a must! If you are starting off from a a healthy weight, by the end of the first trimester (week 13), you should be putting on anywhere between 0.45kg to 2.3kg.



At about 0.33cm, your baby, though small, is already starting to form major organs like his for her heart, liver, kidney and stomach. The little one has three layers, the ectoderm, the mesoderm and the endoderm now.

The top layer, or ectoderm, will give rise to the hair, nails, skin and sweat glands. This layer also consists of the neural tube, from which your baby’s brain, spinal code, nerves and backbone will develop.

The middle layer is the mesoderm, where the heart and circulatory system is beginning to form. This layer will also form the baby’s muscle, cartilage and bone.

The bottom layer, or endoderm, will house the lungs, intestines, liver and pancreas.

Meanwhile, your body already has the primitive placenta and umbilical cord which will begin to deliver nourishment and oxygen to him or her.



Reminders for the week:

  • Take your prenatal vitamins. Most prenatal supplements contain folic acid, iron and calcium. Pregnant women will need more of these nutrients, however don’t overdo the vitamins!
  • Ensure you have your dose of folic acid. Folic acid greatly reduces the risk of birth defects such as spina bifida.
  • Arrange for your prenatal appointment (if you have not already).
  • Stop smoking.
  • Stop drinking alcohol.
  • Start thinking like a mother and keep yourself and your baby safe. Ensure your living environment and workplace is safe. When on the bus and MRT, ensure that you have a comfortable and safe position to be in, should you need to stand.