Conception
During conception, the sperm and the egg most often meet in the fallopian tube (a tube which connects your ovaries to your uterus). One the egg and the sperm connect, it forms a “zygote”. Once the zygote is formed, a brand new DNA structure is created. In this moment, things such as gender, hair colour, eye colour, fingerprint, and height are all determined.
In the next few days, the cells will continue to multiply and become an “embryo”. This embryo will travel down the fallopian tube towards the uterus, getting ready to implant.
3 weeks
21 days after fertilization, the heart begins to beat. The foundation for every organ system has already begun to develop.
5 weeks
At 5 weeks, 6 days, the basic structure for the central nervous system is formed, and arms and leg buds are beginning to develop. The heartbeat can be seen on an ultrasound, beating between 100-120 beats per minute!
1. heart chambers 2. chest and abdominal walls 3. liver 4. marginal vein of left upper hand 5. left wrist 6. pharyngeal arches
7. left upper limb
7 weeks
As you can see in the photo, by 7 weeks the baby has hands that are forming. Depending on the gender, the ovaries or testicles are also beginning to form.
1. forehead 2. left hand 3. placental vessels 4. umbilical vein 5. notches between emerging fingers (digital
rays) 6. digital rays 7. right wrist 8. right hand
9 weeks
At 9 weeks, the nose and ears are developing, which can be seen on an ultrasound. The bones are beginning to harden and calcify.
1. mucous plugs within right and left nostrils 2. lips 3. chin 4. line of fusion, right eye 5. nose 6. nail fields 7. left palm
3 Months
Around 11 weeks, the embryo is now referred to as a “fetus” which means “young one”. The baby can yawn, and suck his or her thumb!
1. right ear 2. umbilical cord near placenta 3. back 4. right elbow 5. abdomen 6. right thigh 7. mouth 8. base of umbilical cord
4 Months
Around 11 weeks, the embryo is now referred to as a “fetus” which means “young one”. The baby can yawn, and suck his or her thumb!
1. right ear 2. umbilical cord near placenta 3. back 4. right elbow 5. abdomen 6. right thigh 7. mouth 8. base of umbilical cord
5 months
Around 5 months, the baby is approximately 10 inches long. He or she loves to sleep, and even has a favourite position to sleep in! Around this time, most women begin to “show”.
1. scalp 2. forehead 3. nose 4. philtrum 5. umbilical cord around neck 6. chest 7. chin 8. eyes closed 9. left ear
6 Months
Around 22 weeks, a male baby’s testicles will begin to descend to his scrotum.
1. eye 2. nose 3. philtrum 4. mouth 5. wrist 6. left forearm
7 months
Following 24 weeks, the baby has a higher chance of surviving, should he or she be born prematurely. Around 28 weeks, a baby weighs approximately 2.5 lbs.
1. nose 2. mouth wide open 3. forehead 4. chin 5. left eye 6. cheek 7. left hand 8. left forearm
8 Months
At this point, the baby is nearing the final stages of development. The lungs are one of the final areas to finish development, so if a baby is born at this point, it will likely need assistance with breathing.
1. forehead 2. philtrum 3. chest
For more images of development, please visit: Endowment for Human Development.
For more information on the stages of development, review: The First 9 Months