First of all, let me congratulate you, because if you are reading this article you are probably pregnant or trying to be soon. During the first nine months of life, a baby grows and develops tremendously, in a matter of a few weeks a baby goes from the size of a grain of rice to a size of small fruit during the first trimester. This growth doesn’t stop there, and the baby keeps growing and developing until birth. In this article I’ll give you an overview of your First Trimester Baby Development by Week so you can know about your baby’s growth and development during this time. This article includes ultrasound images as well.
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First Trimester Baby Development by Week.
Weeks 1–4.
After an egg has been fertilized and implants into the uterine lining, a sac grows around it. In time, this will become the amniotic sac. It will hold the amniotic fluid and protect the embryo from the outside world. This is also the time when the placenta starts to grow, too. This will give the baby food and help from the mother.
You ovulate at the beginning of this week. If a sperm enters your egg, fertilization occurs 12 to 24 hours later. An egg that has already been fertilized begins to divide as it moves through your uterus, splitting into many different types of cells as it does so.
When you’re pregnant, you’ll be carrying a tiny ball of hundreds of rapidly multiplying cells that will one day become your child. Pregnancy hormone hCG is being produced by this blastocyst, which tells your ovaries to stop producing eggs.
Embryo status has now been established for your clump of cells. At this point, you’re around four weeks from the start of your previous menstrual cycle. You might be possible to get a positive result on a home pregnancy test around this time when your next period would typically be due.
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What is happening by the end of week 4th?
In your baby the face and eyes start to form, and the heart starts to beat. By the end of the fourth week, your baby will be about the size of a grain of rice. There are a lot of important things that B vitamins can do for you and your baby’s growth and your health during pregnancy. Getting enough Vitamin B6 and Folic Acid (Vitamin B9) is important for early development, so make sure you are getting enough of these.
Ultrasound image of week 4.
Weeks 5-9.
Your baby’s face continues to grow during the second month of pregnancy. The buds that will one day become limbs begin to grow out of the stem. Various body systems, including the brain, senses, and digestive tract, begin to form. The embryo’s cartilage is gradually replaced by bone. Your baby will be around one inch long by the end of the second month. An ultrasound can detect your baby’s heartbeat after roughly six weeks of gestation. Take prenatal vitamins and fish oil as soon as possible to ensure the health of your baby’s development.
Baby development by Weeks.
- Week 5: Your baby still looks more like a tadpole than a human being, but it is rapidly developing. This week, the “heart” will begin beating, and the circulatory system will begin to form. The baby is the size of an Apple Seed.
- Week 6: Starting to form are your baby’s nasal cavity and mouth along with their ears and ears. Also, they’re developing their intestines and brain. Your baby is now the size of a Sweet Pea.
- Week 7: Since last week, your baby’s weight has doubled, yet he or she still has a tail. Paddle-like hands and feet are emerging from the developing limbs and lower extremities. Your baby is about the size of a Blueberry.
- Week 8: Although you haven’t felt any movement yet, your baby has begun to move around. Primitive neuronal pathways are formed in the brain. As their lungs continue to grow, their throats are now connected to their lungs via breathing tubes. Your baby is now the size of a Raspberry.
- Week 9: Despite the fact that your baby’s basic structure is forming, there is still a long way to go. Even though they are only a few hundredths of an ounce and no longer have an embryonic tail, they are rapidly filling out. Your baby is now the size of a Green Olive.
Ultrasound image of week 9.
Week 10-14.
The hands, feet, fingers, and toes of the baby are fully formed during this stage. They begin to grow on their hands and feet. There is also a start in the development of the external ear and teeth. An ultrasound or sonogram can’t yet tell if a fetus has developed reproductive organs. Approximately an ounce and four inches long, your baby is fully formed by the end of the third month (all organs and extremities are present).
Baby development by Weeks.
- Week 10: The most crucial stage of your embryo’s growth is now accomplished. Although their skin is still translucent, their small limbs may bend and fine characteristics such as nails are beginning to appear. Your baby is roughly the size of a kumquat.
- Week 11: Your fetus is almost complete. Although you can’t feel any motion yet, they’re kicking, stretching, and even hiccupping as their diaphragm develops. Baby is roughly the size of a Lime.
- Week 12: Baby’s reflexes will start to kick in this week: their fingers will start to open and close, their toes will curl, and their mouth will make sucking movements, but you won’t feel them yet. Baby is roughly the size of a Plum.
- Week 13: Your first trimester is coming to an end this week. Fingerprints have formed on your baby’s tiny fingers, and veins and organs are visible through their skin. If you’re having a girl, she’ll have over 2 million eggs in her ovaries. Your little one is about the size of a Lemon.
- Week 14: Your baby’s brain signals have started to fire, and they’re utilizing their face muscles to communicate with you. Their kidneys are now functioning properly as well. Your child is around the size of a Nectarine.
Great news, the likelihood of a miscarriage drops dramatically after the third month of pregnancy or the first trimester.
Ultrasound image of week 14.
Need more information about pregnancy? Check these other articles.
11 Signs of a Really Early Pregnancy.
Pregnancy diet. Proper nutrition during pregnancy.
First trimester checklist for a healthy pregnancy.
Tips to Prepare for a Healthy Pregnancy.
Causes of abnormal bleeding during pregnancy.
Coronavirus and pregnancy. What you need to know.
Final thoughts about First Trimester Baby Development by Week.
Your baby is always growing and developing from the time of conception to the time of birth. They will go through several phases, beginning as a blastocyst, then evolving into an embryo, and finally becoming a fetus, before being born. A baby’s heart will begin to beat at the 5-week mark, and around 27 weeks they will have normal sleep and wake cycles. At 39 weeks, your kid will be fully developed in terms of physical development. Use this pregnancy timeline to find out how large your baby is and how they’re developing throughout the nine months of pregnancy.
The growth and development of human life is a miracle and is exciting to know what’s happening inside your womb. If you have any question about today’s topic don’t hesitate to leave your question below. I hope this article was helpful, don’t forget to check other articles about pregnancy before you go.
Zadi, xo
Disclaimer: The medical information on this post is for educational and entertainment use only. Under no circumstances, this information is to replace your doctor’s advice or to treat any disease. For proper care, always visit your doctor.
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