News for Life Home page

From Embryo to Fetus in the womb : medical facts
by Gloria Poole,R.N.

To see tiny humans in amniotic sac visit this link:

From Embryo to Fetus in the womb : medical facts
by Gloria Poole,R.N.

There are several distinguishing features of the

transition of an embryo to a fetus. Both of these words

are medical terms for a certain stage of development in

the womb. There is no abrupt change from the embryo to

the fetus. Instead there are cumulative changes that are

evolving day to day. The embryo changes from an

amorphous shape to more of a tiny human with all parts.

Also all of the major body organs have either appeared

or the precursor of them has developed.  As the embryo

survives the second month in the womb, and is alive at

the beginning of the third month, the tiny human is less

vulnerable to the effects of disease in the mother, or

radiation of the mother, or medicines the mother may

have taken. Of course women who are pregnant should

never drink alcohol or use drugs! At any stage of the

pregnancy the baby in the womb is harmed by alcohol, and

many drugs have teratogenic effects.  The term fetus is

appropriate after the major organs are either formed

entirely or the precursor of them is present e.g. for

the kidney. The fetus is still vulnerable but not as

much so, since the tiny human has a larger body and

therefore it would take larger doses of medicines

through the placenta to harm the tiny being, and the

tiny baby also has more developed organs to filter the

medicines that might pass to the baby through the

placenta.  At the end of the first month after

fertilization the human embryo is about a quarter of an

inch in length from the top of the flat bulbous like

head to the end of the emerging legs that look at first

like a tail.  Most of the organs are beginning to take

shape as the cells continuously divide and

differentiate. The tiny human develops by a 'blue print'

that is built into the chromosones and genes that the

tiny human received from the mother and from the father.

Twenty-three chromosones come from each parent in most

instances. In Down's syndrome the chromosones are

different. The baby's brain develops first since it is

needed first. The wisdom of GOD in creating humans is

obvious if you really study human anatomy and physiology

much. The outlines of eyes appear and a primitive mouth

and by 30 days after fertilization the three primary

parts of the brain are present , and the eyes, ears, and

nasal passages have begun to develop. The beginnings of

the backbone is present but that first month the tiny

embryo is sort of hunched together in a C shape. There

is no discernible arms or legs yet but the "tail"  will

become legs.  The heart will have started beating even

though it is not completely formed.  The tiny human has 

a closed circulatory system that includes the baby's own

blood vessels and also the umbilical cord and placenta

to the mother. The digestive tract opens from the mouth

downward  for the first time on about the 28 th day

after fertilization by the male sperm. The liver appears

by about the 21 st day after fertilization. The thyroid

gland begins to form. The stomach, intestines,liver and

pancreas are there but there is no anus yet. The lungs

are not developed yet. Lung buds begin about day 27 and

the trachea [windpipe ] appears a few days after that.

By the time the tiny being would be called a fetus he or

she would have gained weight to one gram or about one-

thirtieth of an ounce, which is not as much as an

aspirin tablet but for the tiny human it is significant

progress since it means a 50-fold gain in body mass

gained during the second month over again what the tiny

human weighed at the end of four weeks after

fertilization.  By day 31 muscles appear in the pelvis

and arms and legs begin to form and look sort of like a

bud on a tree in bloom.The valve separating the chambers

of the heart appear on day 31 or soon after. The germ

cells [sex determining] move along the mesoderm toward

the genital ridges and will form either ovaries or

testicles. By day 32 the caudal muscles appear [in what

becomes the baby's behind] and the last pair of gill-

like arches that will develop into lungs appears. By day

33 the cerebral cortex in the brain develops. By day 34

more of the muscles that will become the thighs and legs

develop and the stalk that separates the baby from the

yolk sac lengthens.  By day 35 the primitive germ cells

have arrived in large numbers near the ridge that

develops into the kidney. And the olfactory part of the

brain that regulates small is present in the brain.  By

the fifth week the tiny human is 8 millimeters or one-

third of an inch long from crown to rump and weighs

about 1/1000 of an ounce. The jaws are forming and the

face is beginning to look like a human face. The

umbilical cord is present and is the only part connected

to the placenta. The pituitary gland is forming in the

middle of the brain. The pharynx branches into the two

parts that will go to each lung. The membranes

[peritoneum] that separate the intestines form the chest

have formed and separate the lungs,heart and trachea

from the stomach and intestine.  By day 36 the arm and

legs buds appear, and the 'tail' starts to shrink and

the baby may start moving about.
By day 37 the intestines have grown enough that they are

beginning to curve into their adult shape. The brain

stem that controls respiration is recognizable. By day

38 the jaws of upper and lower begin to look symmetrical

and with an mouth between them and the eye muscles have

begun to form in the orbits. Hands that look more like

paddles form and then when the fingers elongate they

look more like hands. The insides of the baby have grown

so fast that they sort of bulge and could be seen easily

through the almost transparent skin of the baby. By day

39 the nerve fibers are present to connect the sense of

smell of the olfactory nerves. By day 40 the pigment

[color] of the eyes could be seen through the

transparent skin also. The jaws are well formed and the

teeth, and facial muscles are forming also. The gill

arches disappear and the diaphragm appears that moves up

and down in respirations though the baby does not

breathe in the womb but later sort of practices that

effort. The liver starts producing red blood cells and

takes over from the yolk sac. By day 42 the reflexes

being and fingers and toes are more visible and the

beginnings of gonads are visible. By the sixth week the

fetus is 13 millimeters or half an inch long from crown

to rump. Cartilage that will become bone appears. The

head seems huge in relation to the rest of the body and

bends forward onto the chest since baby is still sort of

a C shape. Fingers appear. And the mammary glands begin.

The stomach and intestines rotate into position, muscles

lengthen and both cartilage and bone are visible in the

forming skeleton. The kidney has begun with the

pronephros the first but non-functioning kidneys. By day

44 the retinas of the eyes form, and also the palate of

the mouth and and the canals of the ear. By day 46 the

gonads are formed either ovaries or testicles so the sex

of the baby.  Viola by day 48 after fertilization the

tiny human looks like a human! And is definitely a

/s/ Gloria Poole, R.N. with reference from medical

textbook "From Conception to Birth' by Roberts Rugh and

Landrum B Shettles MDs.

Years ago I wrote the medical facts of how humans develop on another website of mine at: . [This site is down I think because prodeathers hacked into it; but I am leaving this for documentation that the content on it belongs to me]. 

Other PROLIFE blogs I write/ create are: [pencil drawings I drew of stages of human development] is Multilingual scriptures Commandments

and other sites and blogs also.

Copyright notice: This site and its accompanying blog of is intellectual property created by me Gloria Poole of Missouri and it is copyrighted content. It may not be transferred to anyone anywhere, nor printed at remote, nor copied, nor photo-copied, nor saved to disk by anyone [except me of course as creator of it and the original content on it.] . It is covered by U S copyright laws. I , Gloria Poole, RN, artist am a US citizen born in the state of Georgia, and am entitled to all protection of the U S Constitution and U S government. I am a white, single again[ divorced twice] , Southern Baptist Christian woman and the mother of two grown daughters [but no sons] and my daughter's names are Jennifer and Leigh. I am also a republican, prolife activist, artist in all mediums and a Registered Nurse licensed in Missouri. You can read more about me on these blogs of mine: and also my blog in my former married name at

/s/ Gloria Poole, R.N. and artist, written on: 8:17 AM 6/12/2009
Today's date is: 12: 56 PM 6/29/2009
Clostridium Difficile article by Gloria Poole,R.N.:
This site is owned by Gloria Poole, R.N. and artist of MIssouri; my profile page for this is located at:

Read about News for Life at this page:
Read about the deadly risks of elective procedure known as abortion on this webpage:
FYI, I Gloria Poole moved to Missouri on Oct 31, 2009 and I am updating my websites with that info. This site updated with basic info on 1-Dec-2009. Updated again on 19_March-2010 after discovering that the website was down and that many of my original sketches on other sites were stolen by cybercriminal breaking into my internet accounts. I try very hard to maintain quality control but controlling the many criminals lurking on the internet is something even governments do not seem able to do. You may contact me in Missouri via my google phone of 5733429177, or my landline phone in Missouri which is a listed number with the telephone company. 

To see medical photos of how tiny humans look in the womb and amniotic sac, please visit this site:

Return to home page here:

Read about News for Life on this page:

Thank you for viewing this site. 
Info reviewed and updated 12-June-2011, by me Gloria Poole,RN in Missouri. Update: I have been bombarded with cyberattacks from the proaborts, the federal government [attacking me for opposing Obama and H Clinton with words], and by the abominations as GOD calls them for saying they are abominations; but I use the less specific word of perverts most of the time. And by the ordinary cybercriminals seeking to steal money online. I have learned much about what constitutes secure computers and what doesn't.
Gloria Poole, RN and artist. Notice of ownership: this website and this account and the words on it and the images of it belong to me Gloria Poole,RN licensed in Missouri; and I own all rights to my words.poems,essays,paintings,sketches, and drawings of medical illustrations of how human develop in the womb. Updated 19-July-2011 by me Gloria Poole,RN & artist. Updated by me Gloria Poole,RN at my apt in Missouri , 11-Oct-2013 @12:01pm. Updated by me Gloria Poole, RN, artist residing in Missouri 2 July 2014 at 12:08pm [noon] and updated agin on 18 August, 2014 by me Gloria Poole, RN, artist also known as gloriapoole on web. Updated by me Gloria Poole, RN, artist of Missouri 11 Spt 2014 at 5:13pm. Updated 14 Feb 2015 by me Gloria Poole,RN, artist of Missouri. Updated by me Gloria Poole,RN,artist of /in Missouri on 15th Jan 2017 at 3:44pm