Institutional Affiliation
This paper will indicate the stages which take place during pregnancy
from the 1st week to the 40th week.
Week 1
In this week, the mother is not pregnant but the uterus starts to shed
its lining which typically causes some bleeding. This happens because
reproductive hormones are preparing the uterus for an ovum release.
After the sexual intercourse there is the initiation of conception
Week 2
The pregnancy has not yet started at this stage, though the uterus
prepares itself for the incoming fetus. The uterine inside layer
thickens and gets ready for ovulation to occur and in some ladies may
feel a cramp of pain as ovulation takes place. The ovary releases a
mature egg also called the ovum into the fallopian tube, a process
called ovulation. The ovum rests in the tube where it will await the
sperm that have survived the 6- to 8-inch swim through the cervix and
uterus. As the ovulation procedure occurs, millions of sperm released
swim upstream on a search to fertilize an ovum. Unfortunately for all
others, only one sperm will make it.
Week 3
This is the week when an ovum resting at the fallopian tube meets up
with the sperm. When the sperm meets and penetrates the ova
fertilization or conception occurs which marks the beginning of the
pregnancy. After fertilization, your ovaries start ramping up the
production of progesterone Lippincott, Williams & Wilkins 20). The
fertilized ovum is now a zygote and it starts to divide into identical
cells as it hovers down the fallopian tube to the uterus.
Week 4
At this time the zygote finds its nesting position in the uterus and a
lot of action takes place but the mother is completely unaware of. The
little zygote, now called a blastocyst divides in half: one-half
attaches to the uterine wall and forms the placenta which is the
life-support system that nourishes and detoxifies the baby and the other
half becomes the baby (Pera, et al 2010). By the ending of this week,
the baby misses her period which mostly gives you the first indication
that something is up. Some women may experience implantation bleeding
which is a slight spotting that happens when the blastocyst snuggle into
the wall of the uterus.
Week 5
In this week, any pregnancy examination can confirm the pregnancy and
the zygote is about the size of an apple seed and has its own beating
heart. The umbilical cord and the placenta are in full operation and he
baby is rapidly developing with the following features: distinct head
and tail folds, formed primary brain vesicles, well contracting heart
tubes and the nervous system begins to develop.
Week 6
Organogenesis, a period in which the fetus`s vital organs are developing
commence at this stage. It is in this stage that, the fetus is most at
risk from defects that are caused by external factors like drug abuse
(Treece, 2011). This is the week the substantial feelings of pregnancy
usually show as signs of the incredible growth process. These feelings
include fatigue, frequent urination, sore breasts and nausea. The
embryo appears more of a tadpole than human but its body is rapidly
growing. The head and arm buds are recognizable, optic vesicles and
lenses form and limb buds grow. Internal organs like liver, lungs,
thyroid gland, pancreas and heart appear. Blood circulation is well
established and the heart knobs from the body. The cerebral brain
hemispheres start enlarging while the abdomen area and the intestinal
loop are present.
Week 7
The heart is now fully formed, limb buds present, nostrils have
overhanging borders, eyes start appearing, and the head is larger. The
tongue and kidneys begin to form while the trunk of the main body is
lengthening and straightening. The eyelid folds are forming. The
appendix and pancreas are present. The liver ducts, Spleen, pituitary
gland, stomach and esophagus start forming
Week 8
The half an inch long embryo has its leg buds and arm buds divided into
respective units and the limbs are longer. The reproductive organs like
gonads, testes or ovaries start to form. Cartilage and bone are forming
with hands being flexed over the wrists and meet over the heart bulge.
The feet approach the midline and might meet and cartilage appears where
bones will develop. The eyelids and the external ear are highly
developed in form and the head is in a more upright position with a more
developed neck.
Week 9
The abdomen and chest cavities become separated with the eye muscles,
eyes` retinas and eye nerve cells developing while the semicircular
canals of the ears are having some formation. The nerve links from the
retina to the brain are established while the nasal passages are formed
and open to the outside. A discrete neck connects the head to the body.
All fingers and toes are formed while the urinary and rectal passages
are fully disconnected.
Week 10
In month number two the baby is rapidly growing and the mother’s hopes
are high. This is the stage to have a sense of balance between the
discomforts of the hormonal surge with the understanding of the value of
the newborn. The embryo now weighs 1/3 ounce and measures 11/4 inches.
The eyes have are well positioned in the front of the face and neck
muscles are forming. Bones start to replace the cartilage and the
diaphragm starts to divide the heart and lungs from the tummy. The
stomach moves into its normal position and the taste buds start to form.
Testes start to descend in males while clitoris appears in females and
Week 11
The head is almost half the size of the fetus and the eyelids have
merged and will stay that way until week 24. The outer sex organs are
developing and hair follicles of the skin are forming. Teeth are
starting to form and ears are still abnormally short on the sides of the
Week 12
The skeleton of cartilage is forming and the gallbladder can secrete
bile from the fetus with thyroid gland and pancreas also formed
(Meredith, 2013). The lungs are fully formed and the liver is
functioning to make blood cells.
Week 13 and 14
The fetus now measures about three inches long with the stomach, liver,
trachea, lungs, pancreas and intestines develop into their final
functional form. The ears have moved from the neck onto the head and the
vocal cords are complete. The sex organs have fully differentiated into
male or female while the digestive glands are complete. The taste buds
are numerous and the salivary glands form.
By the third month, the baby is fully formed and secure in the womb. The
mother now starts to feel more like normal with less fatigue and nausea.
The mother can now look forward to the time when the baby will grow in
Week 15 and 16
Blood vessels are formed and can be seen through the skin and the legs
are longer than the arms. The fetus can open its mouth, make a fist,
move its lips and swallow. The heart is normally beating 117 to 157
times per minute. The stomach is secreting digestive juices and kidneys
are producing urine.
Week 17 to 20
The rapid growth rate begins to slow down and white fatty material
begins to enclose the nerve fibers of the spinal cord. Between these
weeks, hearing develops and the fetus can perceive sound of both
internal-organ and outside-world sounds. The skeleton is clearly
outlined and ears stand out from the head. Parts of the leg have now
developed in proportion to the body and the mother can experience the
fetus move its arms, kick, and wiggle its fingers and toes. A skin
casing called vernix caseosa develops to guard the baby`s skin from the
amniotic fluid.
Week 21 to 25
The fifth month is a very busy one with the mother’s body changing in
ways that cannot be hidden since she is carrying a baby who`s ready to
grow. Several body organs and continue to grow and mature such as
eyelids and fingernails which become well developed.
Eyebrows and eyelashes are developing and lips are becoming more
distinct with the teeth appearing beneath the gums (Boccio, 2007). Blood
vessels in the lungs are growing and the skin appears wrinkled. If the
baby is born at this time, it would try to breathe and its taste buds
are forming.
Week 26 to 30
The face and the body usually assume the manifestation of an infant at
birth. The baby begins to make breathing actions even though there is no
air in the lungs and it can also respond to touch. The network of nerves
to the ear is developed and the brain tissue continues to develop.
The baby sleeps and wakes at habitual intervals and the baby can now
dream and the baby can roll his head to find the source of light. The
baby seems uneasy waiting to join the world and its kicking and punching
grow to be stronger and more recurrent.
Week 31 to 35
Lungs and digestive track mature gradually and by week 35, they are
fully formed and the baby can see in the womb. Interestingly, if you
shine light on your belly, he might shift his head to track the light or
even reach out to touch it.
Arms and legs are completely proportioned relative to the size of the
head and the baby`s actions might be less regular and less vigorous
because his room to move around is now limited.
Weeks 36 to 39
In this eighth month the mother might feel the pregnancy idea becoming
old but it is time to move on to motherhood. The baby sheds her furry
layer of hair and the skin coating that covers a fetus to shelter the
skin. The baby swallows this waste and will release it as his first
bowel movement. All organs including the lungs are complete and ready to
function outside the womb.
Week 40
This is the due-date week when the baby may make her entrance to the
world. The due dates are not often exact and even carrying a baby to
Week 42 is taken to be normal. The expectation can make even the calmest
expectant mother crazy but it happily ends with the newborn in her arms.
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