1. Month by Month Revised 10/15/10 KBrown
Fetal Development
Month by Month
Revised 10/15/10 KBrown

2. First Month
By the end of the two weeks, the zygote is about the size of a pin head
The heart, no larger than a poppy seed, has begun beating
Zygote has implanted itself to the lining of the uterus and becomes an embryo

3. First Month

4. Two Months
The embryo is about 1/4 inch long at beginning of the month and has distinct, slightly webbed fingers.
Bones begin to form
Face, eyes, ears, and limbs have developed
Veins are clearly visible; heart has divided into right and left chambers
Changes into a fetus at the end of eight weeks

5. Two Months

6. Three Months Fetus is 1 inch long at the beginning of month
Nostrils, mouth, lips, teeth buds, and eyelids form.
Fingers and toes are almost completely developed.
All organs are present, although immature

7. Four Months Beginning of the month size: about
3 inches long; weighs 1 ounce
Can suck thumb, swallow, hiccup, and move around
Covered with a layer of thick, downy hair called lanugo
The heartbeat can be heard clearly
Facial features become clearer

8. 4 months

9. Five Months Fetus is 6 ½-7 inches long and weighs almost 4-5 ounces
Hair, eyelashes, and eyebrows appear.
Teeth continue to develop
Organs are maturing.
Becomes more active.

10. Six Months Length: 8-10 inches long; weight: 8-12 ounces
Baby's lungs are filled with amniotic fluid; he/she has started breathing motions
A protective coating called vernix caseosa begins to form on baby's skin.
If the mother talks or sings, the baby can hear her.

11. 6 Months

12. Seven Months
Beginning of the seventh month, the baby weighs about 1 ½ to 2 pounds and is about inches long
The body is well-formed
Periods of activity are followed by periods of rest and quiet.
Fingernails cover his fingertips

13. Eight Months Size: 14-16” long, weighs about 2 ½ to 3 pounds.
Weight gain continues rapidly
Baby is gaining about half a pound per week, and layers of fat are developing
May react to loud noises with a reflex jerking,
Moves into a head-down position

14. 8 months

15. Nine Months
Fetus is 5 to 6 pounds and 17 to 18 inches long as month begins.
Weight gain continues until week before birth
Skin becomes smooth as fat deposits continue
Movements decrease as the fetus has less room
Acquires antibodies to fight disease from the mother’s blood
Moves into pelvis, ready for birth.

16. Summary
Be able to discuss at least one important fact from each month.