If you are looking for a pregnancy period baby look that can help you track your pregnancy, this is the guide for you.
The baby at 4 weeks is now different from the embryo. The eyes and ears are not yet fully formed but most other organs have developed to a degree that they can be observed with an ultrasound. Baby at four weeks weighs less than 0.1 gram, and has grown in size about 50 times larger than when he or she was just conceived!
The Baby’s length now measures about 1/5th of an inch (8-9 millimeters) while weight is about 0.0003 ounces (100 milligrams). Baby could be easily recognized as a human being by anyone looking for the first time into his or her mother’s womb at this time.
The baby looks like a tadpole
The head makes up more than half of the baby at 4 weeks. At this point in time, the tiny ears have started to form and the arms and legs are visible but not yet fully developed. The baby has distinct gums that will soon turn into the baby’s teeth. The Baby’s eyes are still closed but can be observed with an ultrasound if necessary for diagnostic purposes.
The baby is also starting to develop a neck as tissue between head and body starts to grow in length (this is the first sign of the baby’s future “Adam’s apple” called thyroid cartilage). The umbilical cord which supplies Baby with nourishment via the mother’s blood supply now measures about 1 inch (2 centimeters) long. Baby still does all his or her growing while inside Mommy!
The Baby’s Brain
A Baby at 4 weeks has a brain that is made up of about 50% of the size of an adult brain. Baby starts to move around during this week with spontaneous kicking and fluttering movements, caused by Baby’s muscles spontaneously contracting. The baby also stretches his or her body on a daily basis as Baby gets ready to be born and live life independently.
A 4-week-old baby can detect light stimuli reaching the Baby from the outside world through the mother’s belly. Baby starts opening and closing eyes as eyelids are still thin but well-formed, mostly closed making it difficult to visualize baby’s eyes with ultrasound at this age.
Size comparison with common objects throughout pregnancy
As you notice the size comparison charts, keep in mind that the Baby is still growing and Baby’s size at birth will depend on the Baby’s gestational age – a Baby born 4 weeks prematurely would be much smaller than the same Baby born almost full term!
At 4 weeks: Baby measures 17 mm (less than 3/4th of an inch) from head to toe Baby weighs less than 0.001 ounces (300 milligrams) and is about 1 cm long, or approximately 1/3rd of an inch
Baby’s heart Development
Development of the baby at 4 weeks Baby’s heart, which began beating at about 18 days after conception now has its own blood supply and is pumping Baby’s own blood. Baby’s kidneys are starting to produce urine Baby’s bones start to form as Baby starts developing his or her own muscle movements. Baby:
- Opens and closes eyes (can be observed with ultrasound)
- Starts sucking the thumb
- Can hear sound from the outside world through the mother’s belly
- Baby can grow hair on Baby’s head and around genitals
Amazing to see!
Development of a baby at 4 weeks Baby can visibly react to light, sound or touch – the baby will even “startle” if touched very suddenly! Baby will also turn his or her head towards an object that catches Baby’s attention. If Baby is touched (by ultrasound for example), Baby will show Baby’s displeasure by subtle movements or Baby may even “cry”. Baby’s ability to sense pain is present and Baby can react if Baby feels discomfort.
Baby’s heart rate speeds up when Baby is exposed to a loud sound, in fact, your doctor will listen to Baby’s heartbeat with a device called Doppler (it creates the same effect as shining bright light on an object) – the baby from this age onward appears much more active on ultrasound than before! Baby starts stretching his or her muscles and moving arms and legs about.
Changes in mom’s body and emotions during this time period Baby
The belly button is starting to form and the abdomen still shows some signs of pregnancy as abdominal muscles are stretched.
Dark spots on the skin called “pigmentation” start to develop as Mom may have suntanned throughout her life, or Mom has fair skin that will need some time before these pigments will fade away after birth.
Mom starts having emotional waves up and down – there are so many changes going on both emotionally and physically that it’s easy for a mother to feel sad, excited, and happy all at once! Remember.
Tips on how to care for yourself during pregnancy Baby
The Baby’s heart rate has accelerated. Now he starts to move his or her head around and Baby may even startle easily if Baby is touched very suddenly. Baby hears a lot more in the outside world as Baby’s ears are well-formed at this point Baby can also hear the voice of Mommy and Daddy, but these voices seem somewhat muffled due to amniotic fluid that covers Baby during pregnancy. Baby still does all its growth while inside Mommy.
Congratulations! You’ve made it through the first trimester of your pregnancy
The baby is about 4 weeks and the Baby has been developing at a rapid rate so far during this first trimester, Baby’s brain, bowels, stomach and kidneys are now fully developed. Baby’s beating heart is growing stronger every single day as Baby receives oxygen from his or her own blood supply through Baby’s umbilical cord (which will become Baby’s lifeline upon birth). Baby’s liver is also well developed and helps filter Baby’s blood. So far, Mommy has not felt any movement as movements are too small to be felt by Mom yet; however, Baby can be seen moving on an ultrasound screen.
What to expect next week, month, and year with a new life growing inside you Baby
The embryo Baby will start to gain Baby’s first layer of fat Baby’s face is still forming in the shape of a little football, Baby has two bulges where Baby’s eyes and mouth are later formed. Baby’s skin is transparent as if Mom could see Baby’s insides through Baby’s skin. At this point, Mommy can look at images from an ultrasound machine to check on Baby’s progress and any problems that may occur during pregnancy.
What will happen during your next visit?
Next week, expect your doctor or midwife to measure the Baby (using centimeters or inches) and weigh the Baby (in grams). He or she will also listen to Baby’s heartbeat using a device called Doppler. The baby may also be given the Baby’s first vaccination during this visit. Baby should not be measured from head to toe until Baby is 28 days old.
As Baby’s crown-to-rump length (distance from the top of Baby’s head to Baby’s bottom) might provide more accurate measurements at that later stage in pregnancy, which is about 5 weeks after the last menstrual period. Baby’s arms and legs will still seem too small for his or her body at this point and eyes are still closed tightly, but it won’t be long before Baby starts developing more rapidly. If you have any questions, feel free to leave a comment below.