Approximate Timetable of Prenatal Development Prenatal Development is divided into 3 trimesters. 1st two months the developing human is called an embryo – from which all body organs develop 2nd trimester he/she is called a fetus. The 3rd trimester the baby is growing and could survive with medical care if born prematurely. Ultrasound picture

It is divided into Trimesters (3) How Long is Pregnancy? The “average” pregnancy lasts approximately 40 weeks. That really is more like 9 ½ months than 9 months. Babies born before 37 weeks are premature and those born after 42 weeks are post mature It’s better to measure pregnancy in weeks than in months It is divided into Trimesters (3)

Where does life begin? Scientifically – When the ovum and sperm meet and the ovum (egg) becomes fertilized it is both human – and alive. So – the answer really is that life begins at conception. This normally happens in the fallopian tubes. The fertilized ovum then moves to the uterus where it should implant to continue growing and maturing

From conception to this! What a Miracle!!! So – how does this happen?

First Trimester 1st – 12th week 8 wks First month – early formation of the layers of cells that become the organs Amniotic sac forms – (water) By the end, the embryo is about ¼” Second month Grows to about 1 ½”. Bones and muscles round out contours of body, forehead prominent, heart begins beating, limbs elongate, sex organs begin to form

First Trimester 3rd month Beginning of “fetal” period Male sexual organs showing more rapidly than female Tooth buds for all 20 baby teeth Organs begin functioning Movement of arms, legs, shoulders, and fingers possible Mother will not feel the movement yet. 3.5 months

Second Trimester 4th – 6th months (13th week to 26th week) Lower parts of body grow rapidly so that head appears more normal Back straightens, hands and feet well formed. More movement – begins to be felt by mother 5th month Skin structures attain final form, sweat and sebaceous (oil) glands functioning. Hair, nails on fingers and toes Lean and wrinkled About 1 foot long and weighs about 1 pound ↑ 4 mos ↓ 5mos

2nd trimester 6th month Eyelids which were fused shut, reopen. Eyes are completely formed Taste buds on tongue (more than we have!) Development mostly over – growth to occur now. Would have chance if born after 24 weeks

Third Trimester 27th week to birth 7th month Capable of living from this point Baby can respond to light, music, sound About 15” long, 3 lbs 8th and 9th month Time to “fatten up”! Formation finished. Lots of movement and activity! Rapid fetal heart rate