The first eight weeks of gestational life (after fertilisation) are termed the embryonic period. All organs, systems and tissues are put in place during this eight week period. The remaining 30-34 weeks spent in the mother's uterus are for growth, development and refinement of these organs, systems and tissues. So, if something goes wrong in the first eight weeks, it may result in a defectively designed structure or system whereas, if the problem occurs after the eighth week, it will more likely result in a failure of growth, development or refinement of the involved structure or system. This latter situation is more amenable to treatment.

By the end of the third gestational week of embryonic life a lot has happened. There are certain folds/curves that have occurred in the embryo that signify the beginnings of brain formation. The primary divisions of the brain are now visible. These are precursors of eyes and ears, and are spoken of as ocular and auditory vesicles, respectively. A primary system for blood circulation is established and a rudimentary heart is starting to beat. The mouth to anus alimentary canal is formed. It connects with the yolk sac as a source of nourishment. The ends of arms and legs are present. A pouch-like formation (diverticulation) in the primitive oral cavity appears during the third week. By the end of the sixth week this has become the pituitary gland. [The pituitary gland orchestrates the endocrine system.] Brachial arches are present, which in fish will become gills, but in the human embryo they will form many of the structures of the head and neck. The beginnings of the urinary system and excretory organs called Wolffian bodies are present. This is a great deal of work and development that has happened in just three weeks.

During the third and fourth weeks certain cells make a cartilaginous plate which forms a floor, a base for the skull. Ultimately, this cartilage will calcify and the bones of the floor of the skull will be the result. The foramen magnum (Latin = big hole) forms. This is the hole in the base of the skull which allows the spinal cord to pass through and become one with the brain. The outer surface of the skull comes from the membrane that encases the primitive brain. The membrane calcifies and forms the bones of the skull vault and this process continues almost throughout the whole pregnancy and until the fontanels are closed during infancy.

During the fourth week more rapid development takes place. The embryo is about three to four millimetres long. The beginnings of an umbilicus/belly button is present. The arms and legs are growing rapidly. The anus and rectum, called a cloaca at this stage, are developing. During this fourth week the rudimentary heart divides into right and left sides. It began as a two-chambered pump and now it becomes a four-chambered pump. The lungs and pancreas develop. The face develops and the openings for the nose become apparent. Special nerve ganglia (centres) and motor nerve roots from the spinal cord are now visible. Cells that form the vertebral column migrate and surround the newly forming spinal cord. Things are moving very, very quickly.

By the end of the fourth week the marginal layer nerve fibres appear. During this developmental process, we have millions and perhaps billions of young neurons discovering just where they belong anatomically. They go to the correct destinations with a very high degree of accuracy, and once there send out connecting fibres that can grow to one plus metres in length. These connecting fibres travel through a maze of other fibres and tissues to their assigned destinations where they begin to function correctly. This is probably the most effectively engineered process that one can imagine.

Whew, what a lot has happened and you're probably not even aware that you're pregnant yet! So, if you're trying for a baby it's a good idea to make sure that the building blocks for the baby are optimum i.e. Mum and Dad. Take a few months to make sure you're physically very healthy.

At five weeks the embryo measures 1/5 - 1/3 inch from head to tail bone. This is a very busy time of development for the embryo. Hands and feet begin to be seen at the ends of the legs and arms, which grow faster than the legs. At the same time the nose, eyes and ears begin to develop as does the pituitary gland (master gland of the endocrine system). The blood vessels that connect mother to embryo are developed now in one of the membrane layers that surround the embryo. The two chambered pump developed in the first four weeks separates vertically creating the right and left sides of a four chambered heart.

Bony developments appearing now are the lower jaw and collar bones. The brain and spinal cord are developing very quickly during this fifth week. We see the beginnings of the motor nervous system that drives the contraction and relaxation of muscles. The foundations of the autonomic nervous system are laid. This system functions beneath our level of awareness and innervates organs and tissues that are called on to help your body respond to increased levels of stress and adversity. [Can you imagine knowing what goes on in you liver, the arteries to you feet, every sensation in your skin, muscles and bones etc 24 hours a day!] Brain development is very rapid. All twelve cranial nerves now develop. The 10th cranial nerve, the vagus, can become trapped and/or can receive undue pressure at the base of the skull during delivery. “The result of this is a colicky baby or baby who doesn't breathe or swallow very well.” It's an easy procedure for a CranioSacral practitioner to relieve this.

The embryo grows to a length of about 3/8 - 5/8 inch during the sixth week. The legs and arms continue to develop. Cartilage development in the vertebral column, the skull and ribs is visible during this week. By the end of the week the tongue, larynx (voice box) the germs that will become the teeth, the rudimentary thyroid gland, the kidneys, the bladder and the beginnings of the genitals are all present. The nervous system and brain continue to develop and grow and the meningeal membrane system which contains the brain and spinal cord is apparent.

During the seventh week the embryo will reach a length of ¾ - 1 inch. Newly formed fingers and hands begin to move. Visible now are the internal organs and differentiated genitals. So you can determine the sex of your baby from the seventh week.

This week sees the first ossification (formation of bone) from cartilage in the skull, ribs, shoulder blades, the bones of the arms and legs and the hard palate of the mouth. The nervous system makes a huge leap in development. The grey and white matter of the brain is created and the muscles that will take their orders from the motor part of the nervous system are apparent. These muscles begin to move during the seventh week of embryonic life. The pupil of the eye forms and the nose becomes more prominent. The eyelids and ears can be seen and the neck begins to lengthen. “The upper lips are formed and will be completed by the end of the eight week. Interference with this process during the seventh and eight weeks by disease, toxicity, emotional upset and the like may result in a harelip.”

Remarkable development is going on in the brain. The pineal gland is formed in the back subdivision of the primitive forebrain. “The pineal gland is highly controversial even today.” There are many beliefs relating to this gland, some of which are that it relates to the circadian rhythms / it is involved in the immune system / it is a part of the magnetic system that keeps us oriented within the magnetic field of the earth.

The eighth week marks the end of the embryonic period of gestation and the embryo will measure about 1?- 1¼ inches. All the organ systems are now established and from now on these systems will develop and refine, but all the foundations are now laid.

Finger and toe joints and the clefts between fingers and toes are present. Upper and lower divisions of arms and legs are now distinct and the ossification of the bones of these limbs and the hip bones is visible. The vertebrae are now cartilaginous and the two halves of the hard palate have united. Salivary glands are present and the heart is well developed. The spleen and the beginnings of the adrenal glands are present and the lenses in the eyes begin to develop and the membrane covering the pupil of the eyes is present.

“Clinically the significance of the end of this embryonic period of development is simply that problems during the first eight weeks of pregnancy usually result in a defective design or the absence of a part or structure within a given system in the newborn. Since after the eighth week all of the building blocks for all of the systems are present, problems that appear in the second phase (foetal phase) of the pregnancy result in lack of growth and or development for the affected part of the system. The latter situation offers greater hope of remediation by treatment than does the former.”

CranioSacral Therapy helps with this and helps make sure all Mum's and baby's systems are working well so that the foetus has the best possible chance. It also helps with the change the pelvis needs to make to during last stages of pregnancy and delivery.

The 7th cranial nerve (facial nerve - facial expression, taste buds etc ) and the 8th cranial nerve (vestibulocochlear nerve - hearing and balance) pass through these bones. There are four muscles that can affect the status of this bone. The most powerful and important two that directly affect the temporals are the sternocleidomastoid muscle (from collar bone to ear) and the temporalis (from mandible over the side of the skull in a fan shape). The other two are neck muscles, longissimus capitus and splenius capitus (aren't they grand sounding names?) The strong mandible (lower jaw) hangs from the temporals and so plays an important part in its balance.

Whiplash, anger, suppressed rage, anxiety and tension affect the balance of the temporal bones via tension in the TMJ (tempormandibular joint - the joint where the mandible articulates with the temporal bone), sternocleidomastoid and temporalis muscles. Low impact trauma, such as falling on the grass while running can also displace the temporals. Compression and ongoing tension of the facial nerve can result in Bell's Palsy. The very short auditory tubes of infants readily allow bacterial infections to spread from the back of the throat (nasopharynx) to the inner ear. Breast feeding can help reduce ear infections in the newborn by up to 50%.

Balancing the temporal bones can help tinnitus, vertigo, nausea, hearing impairment or loss, autism, and personality changes after a whiplash injury. It can also be helpful for depression as balancing this bone can be create euphoria.