First Trimester: 5 Weeks Pregnant

At 5 weeks of pregnancy, you would have definitely gotten a positive result.

You would have already taken a pregnancy test or went to the doctor to get your results confirmed.

At five weeks, the embryo is starting to develop rapidly. While changes in your body might still be subtle, they are already underway. 

This early stage of pregnancy is crucial for the development of your baby. It marks the beginning of some of the most significant growth spurts in the entire nine-month journey.

Your Baby at Five Weeks

By the fifth week, the baby is still extremely tiny. They are often compared to a sesame seed in size, measuring about 1.5 to 2 millimetres long. 

Though small, this week marks the beginning of major developments. Additionally, the baby is now an embryo, and its cells are multiplying at an astonishing rate. 

During this week, key structures begin to form. Your baby’s brain, heart, spine, and other vital organs.

At this point in your pregnant, the embryo is in the process of developing three primary layers of cells:

1. Ectoderm (outer layer): This layer will form the nervous system, brain, skin, and hair. The neural tube, which will eventually become the baby’s brain and spinal cord, starts to develop in this week.
2. Mesoderm (middle layer): The mesoderm will become the baby’s heart, muscles, bones, blood vessels, and kidneys. The heart begins to form as a simple tube and will soon start beating, even though it may not be detectable by ultrasound yet.
3. Endoderm (inner layer): This layer is responsible for developing the baby’s lungs, intestines, and other digestive organs.

While the baby may still look like a tiny dot on an ultrasound, these three layers will continue to evolve into the essential structures and systems of your baby’s body. 

Here are other things that are happening with your body:

• Neural tube: At the fold of the top layer of the embryo is the neural tube, which will develop into the baby’s brain, spinal cord, nerves, and backbone.
• Primitive placenta: The tiny blood vessels (villi) that make up the primitive placenta deliver nourishment and oxygen to the embryo.
• Yolk sac: The yolk sac will soon yield its job delivering nutrients to the developing placenta.
• Amniotic sac: The amniotic sac now houses the embryo, which floats in a growing sea of amniotic fluid.

Your Body at Five Weeks

At 5 week of pregnancy, your body is adjusting to the new life growing inside you. 

Hormones are rapidly increasing, particularly human chorionic gonadotropin (hCG), progesterone, and oestrogen.

These hormones play critical roles in supporting the pregnancy and preparing your body for the months ahead. 

Here are the symptoms that you may start experiencing:

• Missed period: If you haven’t had a menstrual cycle by week five, it’s one of the first clear signs that you’re pregnant.
• Fatigue: Many women start feeling extremely tired around this time. Your body is working hard to support the growing embryo, and hormonal fluctuations can make you feel more exhausted than usual.
• Nausea and morning sickness: Though not all women experience it, nausea, often referred to as morning sickness, can begin in the fifth week. Despite its name, it can happen at any time of the day. This is due to the increasing levels of hCG and oestrogen in your body.
• Breast tenderness: The hormonal changes can cause your breasts to feel swollen, sore, or tender. This is one of the earliest signs of pregnancy for many women.
• Frequent urination: The increase in blood flow and your growing uterus puts pressure on your bladder, causing you to feel the need to urinate more often.
• Mood swings: Fluctuating hormones can impact your emotions, making you feel more sensitive, irritable, or even anxious during this early stage.

While some women may experience all of these symptoms, others may have very few or none at all.

Every pregnancy is unique, so it’s important to listen to your body and consult your healthcare provider if you have any concerns.

First Trimester Reminders

It’s essential to care for your body during this time.

While it will still be weeks before you go for your first official prenatal check-up you may have already gone to the doctor to confirm your pregnancy. 

You may of course use this time to do your research and shop around for another hospital or doctor of your choice.

If you have, the doctor would have already briefed you on all these things:

• Eat a balanced diet rich in vitamins and minerals – start taking folic acid if you haven’t already
• Avoid alcohol, smoking, and harmful substances
• Select a prenatal vitamin – although your doctor will probably have recommended you some when you go for your first prenatal doctor’s visit
• Review medications that you are taking whether it is safe to continue during pregnancy – check with your doctor first before stopping any medication

Sharing the Good News

At 5 weeks of pregnancy, the doctor would have officially declared you a mother.

But this is still just the very first few weeks of your first trimester. Your journey has only just begun.

There’s still a lot more that you will learn about as your pregnancy progresses, especially if you are a first-time mum.

But for now, relax and enjoy the ride. Bask in the glow of imminent motherhood and share the wonderful news with your loved ones (or once you’re ready), mummies!

References

1. Ansari, A. (2023, May 1). Embryology, ectoderm. StatPearls [Internet]. Retrieved November 8, 2024 from https://www.ncbi.nlm.nih.gov/books/NBK539836/.
2. Ertmann, Ruth Kirk, Nicolaisdottir, D. R., Kragstrup, J., Overbeck, G., Kriegbaum, M., & Siersma, V. (2023, January). The predictive value of common symptoms in early pregnancy for complications later in pregnancy and at birth. Acta obstetricia et gynecologica Scandinavica. Retrieved November 8, 2024 from https://pmc.ncbi.nlm.nih.gov/articles/PMC9780714/
3. Karrar, S. A. (2024a, August 12). Initial antepartum care. StatPearls [Internet]. Retrieved November 8, 2024 from https://www.ncbi.nlm.nih.gov/books/NBK570635/
4. Naidu, K. (2023, July 24). Gestational age assessment. StatPearls [Internet]. Retrieved November 8, 2024 from https://www.ncbi.nlm.nih.gov/books/NBK526000/