nuhahyearlyLaunch pricing - Get £50 off!nuhahyearlyAt week 5, your baby is about the size of a sesame seed. A tiny heart tube is beginning to beat and the neural tube - which becomes the brain and spinal cord - is forming. According to Nuhah's pregnancy guide, this is one of the most important weeks for early development.
A tiny heart tube begins to beat, though it is too small to hear on any scan yet. The neural tube, which will become the brain and spinal cord, has already begun forming and closing during weeks 3-4, which is why starting folic acid before conception is so important. Three layers of cells are developing: the ectoderm (skin and nervous system), mesoderm (muscles, bones, heart), and endoderm (digestive system, lungs). The foundations of every major organ are being established.
Morning sickness may begin this week, though many people do not experience it until week 6-8. Rising hCG levels can cause nausea, breast tenderness, frequent urination, and intense fatigue. You may also notice a heightened sense of smell or food aversions. Emotionally, you may feel excited, anxious, or a mixture of both - all completely normal.
The heart tube begins to beat around week 5-6, though it is too early to hear it. A heartbeat is usually visible on ultrasound from around week 6-7. The first time you will hear it is typically at your dating scan around week 12.
Folic acid helps the neural tube develop properly during weeks 3-12. The neural tube becomes the brain and spinal cord. Taking 400 micrograms daily significantly reduces the risk of neural tube conditions. The NHS recommends it from before conception until at least week 12.
Morning sickness typically begins between weeks 5-8 and peaks around weeks 8-12. Despite the name, nausea can happen at any time of day. Around 70-80% of pregnant people experience some form of nausea in the first trimester.
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