Biologically speaking, fertilization (or conception) is the beginning of human development. Fertilization normally occurs within several hours of ovulation. The result is a single-cell embryo called a zygote and it is the first cell of the human body.
The zygote is encased by its protective covering and contains 46 unique chromosomes with the entire genetic blueprint of a new individual. Chromosomes contain tightly packed, tightly coiled molecules called DNA. Amazingly, DNA contains all the instructions needed for this single-cell embryo to develop into an adult.
The primary event of the second week is implantation. Once superficial implantation occurs, the embryo begins receiving nourishment directly from the cells lining the mother’s uterus.
As implantation is underway a structure called the yolk sac forms. The yolk sac is a structure that provides nutrients from the mother to the embryo before the placenta is ready to function. The epiblast also gives rise to the entire head and body of the embryo.
Approximately 8 days after fertilization, cells from the growing embryo begin producing a hormone called human chorionic gonadotropin .This hormone is present in a pregnant woman’s blood and urine almost immediately and is the substance detected by most pregnancy tests. HCG interrupts the normal menstrual cycle allowing pregnancy to continue.
[Ref: Prenatal Overview by the Endowment for Human Development]
Baby Development Area
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Omnio Activity
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Props /Assistance
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Physical Development
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Focus on Nature with relaxed breathing
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Open Areas like parks, garden etc
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Emotional Development
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Resolve to remain unperturbed with the emotion of Fear; if it surfaces repeatedly educate your child to reject it through mind talk
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Intellectual Development
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Subliminal Sama Veda chants - use an authentic Vedic chanting audio file and play it before you sleep allowing it to continue through your sleep time.
Do not use ear phones.
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Sama Veda Chanting
CD
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Sensorial Development
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Focus on textures, smells and tastes in the kitchen/house
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Grains, Vegetables, Food Stuff available in the kitchen
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Creative Development
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Start a small size Cross Stitch job : choose a geometric design and use VIBGYOR colours.
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A small piece of Cloth to be made into a Hand Kerchief, Table cloth etc
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Spiritual Development
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Reconcile with your Parents any childhood issues weighing heavily on your mind. Express gratitude and forgive unconditionally
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If you are in a different place, make a special phone call to them.
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Devotional Development
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Crystallise your intention for child birth with a deity or a devotional icon
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Choose an Idol or Photograph of a Deity like Krishna, Lakshmi etc.
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Once implantation is complete, the embryo continues to grow
inside the wall of the uterus. It’s hard to believe, but development progresses
so quickly that just 10 days after implantation is complete, the embryo’s heart
begins to beat!
Even before a
woman is noticeably pregnant, her intake of food and beverage passes through
the developing placenta and umbilical cord to nourish (or harm) the growing
embryo. The use of harmful substances during pregnancy is doubly damaging
because the woman and embryo / fetus may suffer significant harm.
Following
implantation, maternal and embryonic tissues combine and begin to form the placenta.
Once the placental circulation is in place; nutrients,
oxygen, vitamins, and water in the mother’s blood stream pass through the
placenta and umbilical cord to the embryo (and later the fetus); while carbon
dioxide and other waste flows back to the mother. The placenta also
produces hormones and maintains fetal temperature above the mother’s
temperature - between approximately 100.7 to 102.5 degrees Fahrenheit or 38.2
to 39.2 degrees Celsius. A twisting cord of blood vessels, called the umbilical cord, connects the embryo to the placenta. The best intensive care
units found in modern hospitals hardly rival the placenta’s life-support
capabilities.
By about 15 days (2 weeks, 1 day)
following fertilization, stem cells have divided and differentiated into three
different germ layers called ectoderm, endoderm, and mesoderm. Each gives rise to major components of specific body
structures and organs. Ectoderm derivatives include the skin, nails, hair
follicles, sweat glands, and nerves within the lungs. Another specialized
layer of cells appearing at this time is the neuroectoderm, which gives rise to the brain, spinal cord, and peripheral
nerves, as well as many of the muscles and bones in the face.
Endoderm forms the lining of the respiratory and gastrointestinal
tracts and gives rise to major portions of internal organs including the lungs,
liver, pancreas, and intestines.
Mesoderm derivatives include the heart, kidneys, bones,
muscles, and blood vessels as well as portions of the reproductive and urinary
systems. Mesoderm also gives rise to specialized cells called somites. These cells form most of
the skull and ribs as well as the vertebral column or backbone. All of these
cell layers and cell types work in concert forming the increasingly complex
embryo.
By day 17 the
central portion of the thyroid gland appears. The embryo’s respiratory system begins to develop by 3 weeks
with an outgrowth of the foregut which will form the windpipe.
The site of future brain development is first recognizable
with the appearance of the neural plate by 2 weeks, 4 days. By 3 weeks the
neural plate thickens first at the head end of the embryo and folds into the
neural tube which will form the brain and the spinal cord. By
3 weeks, the 3 primary sections of the brain are identifiable. These sections
are called the forebrain,
midbrain, and hindbrain.
The complexity
achieved by the embryo in just the first 3 weeks of development is incredible.
Considering the importance of distributing nutrients to the emerging brain and
spinal cord, as well as the rest of the embryo, the early development of the
circulatory system is not surprising.
Yet the early completion of this body system – the first
system to begin functioning – is remarkable. By 3 weeks early blood
cell precursors appear in the yolk sac. Also by 3 weeks, early blood vessels
form throughout the embryo as the network of the early circulatory system
begins to take shape. In the middle of week 3, only 18 days after fertilization,
the embryo’s heart appears.
Only 3 weeks and 1
day after fertilization - the heart begins to beat. By
4 weeks, the heart typically beats between 105 and 121 times per minute. Between fertilization and birth, the heart
beats approximately 54 million times, while over the course of an 80-year
lifespan, the heart beats over 3.2 billion (3.2 × 109) times!
Between 3 and 4 weeks, the body plan emerges as rapid growth
of the relatively flat embryo - particularly that of the central nervous
system, causes a dramatic folding of the embryo. This folding forms the
chest and abdominal cavities and incorporates a portion of the yolk sac which
becomes the lining of the digestive and respiratory tracts. Thus,
development of the digestive system is underway just 4 weeks after
fertilization.
Upper and lower limb buds appear by four weeks. Somites will also form the bones
of the spinal column, skull, sternum, and ribs. Skeletal muscles eventually
enable you to move your body.
A transparent sac called the amnion which was formed by 2 weeks, begins to surround the entire
embryo by four weeks. Filled with amniotic fluid, this sterile liquid suspends and protects the developing
embryo. This fluid also facilitates lung development, allows swallowing, and
later provides nutrients.
