Your Pregnancy at 5 Weeks

Your Pregnancy at 5 Weeks

Last update: 28 July, 2018

The fifth week of pregnancy is equivalent to your third week of gestation. The embryo has been implanted in the uterus and now receives nourishment from the amniotic sac. The placenta is still developing. At 5 weeks, you’re likely to suffer nausea, swelling and other associated symptoms.

After taking a pregnancy test and getting a positive result, you should head to the doctor. Your doctor will be able to confirm your condition with more precision. He or she will also indicate any further studies that you might need .

Blood work and urine analysis will help track the development of the fetus, as will ultrasounds. If you’re over 35, then your doctor will likely order more specific testing. This will include amniocentesis. 

These types of studies don’t involve risks. Just the same, they are completely voluntary. If a woman doesn’t want to partake in this sort of study, she is under no obligation. However, it’s useful for detecting certain anomalies, such as Down Syndrome.

What occurs at 5 weeks of pregnancy?

During the 5th week of pregnancy, it’s important to be absolutely sure you’re going to have a baby. The embryo measures between 0.5 and 1 inch, and has a C shape. In the next few weeks, his body will start taking shape. You’ll be able to observe these changes in ultrasound images.

This phase in the baby’s development is called the trilaminar period. The name comes from the gastrulation process in which the germinal layers form. These layers consist of the ectoderm, the endoderm and the mesoderm. Each of these layers has a specific, fundamental function.

The ectoderm is responsible for forming the central nervous system. At the same time, the endoderm forms the pancreas, liver, intestines and thyroid glands. Lastly, the mesoderm forms the baby’s bones, muscles and circulatory system.

Your Pregnancy at 5 Weeks

At 5 weeks of pregnancy, the foundations of fetal development are laid. With the finalization of gastrulation, some of the cells in the mesoderm will be responsible for creating the blood vessels that form the tertiary chorionic villus.

These blood vessels create a connection with the embryo through veins in the umbilical cordFinally, communication is established between the fetus and the placenta. This, in turn, produces the final functioning of the cardiovascular system.

Making the decision to have a child is momentous. It is to decide forever to have your heart go walking around outside your body.

–Elizabeth Stone–

First signs of the heart at 5 weeks

At this point, a small lump begins to form within the embryonic tissue. This is the heart. The baby is located between two protective membranes that form the yolk sac, from which blood cells will emerge.

Meanwhile, the neural tube starts to expand in order to create the front part of the brain. On its sides, blocks of tissue will form that will eventually become muscles. At the same time, meninges and suprarenal glands will emerge from the neural crest.

When should I start to modify my habits?

If your habits are detrimental to your health or that of your baby, now is the time for a change. You should eliminate all alcohol, tobacco and caffeinated drinks for the duration of your pregnancy. Try to substitute them with homemade juices, infusions that don’t contain theine, or just plain water.

Your Pregnancy at 5 Weeks

This is a good time to pick up a light sport to stay fit. Remember that pregnancy is not an illness and nothing will happen to your baby as long as you’re careful.

Avoid excessive exercise and activities that require abrupt movements. Prenatal yoga and swimming are both beneficial for your muscles and spinal column. They also improve your breathing capacity. Going for a brisk walk is also a good way to relax and stay active.

Remember that it’s extremely important that you see your OB/GYN regularly and follow his or her advice. This is the only way to be sure that your child is developing adequately and that there are no problems. Don’t be afraid to discuss any doubts you may have regarding pregnancy and birth with your doctor.

Many first-time mothers are afraid of giving birth, so there’s no need to feel ashamed if you’re feeling nervous. This is a natural process that most mothers go through at some point, so you’re sure to find someone who understands. And when you finally hold your little one in your arms, you’ll realize it was all more than worth it.


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.


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This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.