Appendix 1
The Chronological Development of The Unborn Child

 

Eighth Week

 

Timing

Source
The adrenal glands are developing. 8th week after conception Rugh, p 53
By using Doppler or real-time ultrasonic measurements, the brain can be visualized. 8th week after fertilization Williams, p 30
The chin is visible. 8th ewek after fertilization England, p 81
Ossification begins in the lower limbs, and is first recognizable in the femur. 8th week after fertilization Moore, p 97
The feet are well-formed and distinctly human. 8th week after conception Rugh, p 53
Local stimuli may induce partial closing of the fingers. 8th week after fertilization Williams, p 169
The hands are well-formed and distinctly human. 8th week after conception Rugh, p 53
Hiccups were observed in 12 of 12 fetuses studied, with a median frequency of about 50 hiccups per hour. 8th week after conception de Vries (1985), p 108
The permanent kidneys are forming. 8th week after conception Rugh, p 54
The lungs have lobes and many-branched bronchioles. 8th week after conception Rugh, p 53
Purposeful limb movements first occur. 8th week after fertilization Moore, p 97
Local stimuli may evoke opening the mouth. 8th week after fertilization Williams, p 169
If the fetus is removed from the uterus, spontaneous movements may be observed. 8th week after fertilization Wiliams, p 169
The beginnings of all essential structures are present. 8th week after fertilization Williams, p 154
Local stimuli may evoke squinting. 8th week after fertilization Williams, p 169
Taste buds begin to form. 8th week after conception Rugh, p 53
The ovary is present. 8th week after fertilization England, p 167
Breathing movements are first seen. 8th wek after conception Roodenburg, p 32
A single, large displacement of the diaphragm is sometimes similar to a sigh. 8th week after conception Nijhuis/de Vries, p 6
Insertion of the fingers into the mouth has been observed. 8th week after conception Nijhuis/de Vries, p 7
Stretches first occur. 8th week after conception Roodenburg, p 33
Dental buds are present. 8th week Sadler, 7th edition, p 341
Jaw openings first occur. 8 1/2 - 10 1/2 weeks after conception Nijhuis/de Vries, p 5
Forward head movements first occur. 8 1/2 - 12 1/2 weeks after conception Nijhuis/de Vries, p 5
Stretches first occur. 8 1/2 - 13 1/2 weeks after conception Nijhuis/de Vries, p 5
The auricles of the external ear start to take on their final shape. End of 8th week after fertilization Moore, p 100
The eyelids are closing. End of 8th week after fertilization Moore p 99-100
By the end of the 8th week after conception, the face clearly looks human. End of 8th week after fertilization Moore, p 239
All areas of the limbs are apparent. In addition, the digits have lengthened and are completely separated. End of week 8 after fertilization Moore, p 97
The neck region is established. End of 8th week after fertilization Moore, p 99
The neck is developed. End of 8th week after fertilization England, p 96
The term embryo refers to the developing human being during the first eight weeks after conception. At the end of this period, all major structures have started to form. End of 8th week after fertilization Moore, p 3
The embryonic period concludes at the end of the 8th week after fertilization and the fetal period begins. Few, if any, new structures are formed after this time. Develpment during the fetal period involves growth and maturation of structures that are already present. End of 8th week after fertilization Williams, p 153
The embryonic period consists of the first eight weeks after the last ovulation. During this time, the overwhelming majority ( several thousand) of the named human structures appear, and the embryo is about 30 millimeters in length. End of 8th week O'Rahilly, p 55
Scientists have examined the embryonic period in far greater detail than the fetal period, which begins in the ninth week and continues until birth. Few new features appear during the fetal period. Instead, the structures that are already present continue to develop. End of 8th week O'Rahilly, p 55
The initial formation and development of nearly all of the organs is complete and the organs can be identified in a grossly recognizable state. End of 8th week of pregnancy Carlson, p 407
The head is disproportionately large compared with the rest of the body. End of 8th week of pregnancy Carlson, p 407
The embryo has human characteristics. The neck area is established and the eyelids are obvious and are closing. The auricles of the external ears begin to take their final shape. End of 8th week after fertilization Moore, p 99
The face is unmistakably human. 2nd month after conception Rugh, p 54
Breathing movements are first seen. 8-9 1/2 weeks after conception Nijhuis/de Vries, p 5
Hand-to-face contacts first occur. 8 - 10 1/2 weeks after conception Nijhuis/de Vries, p 5
The hand touches the face slowly and the fingers often open and close. 8 - 10 1/2 weeks after conception de Vries (1982), p 309 & p 311
Limb movements first occur during the 8th week. By the 14th week, they become coordinated. 8th - 14th weeks after fertilization Moore, p 112
External examination can reveal whether the embryo is male or female. Day 50 after conception Rugh, p 7
The face is more human-like. Days 50 - 56 after fertilization Sadler, p 110
The fingers are free. Days 50-56 Sadler, p 110
The limbs are long and bent at the elbows and knees. Days 50-56 of development Sadler, p 110
The toes are free. Days 50-56 Sadler, p 110
The hand plates are slightly flexed at the wrists. Day 52 of devleopment Larsen, p 209
The upper limbs are slightly bent at the elbows. Day 52 of development Larsen, p 209
The eye is heavily pigmented. About 52 days after fertilization Moore, p 100
The fingers are separated. About day 52 after fertilization Moore, p 100
The nose is stubby. About day 52 after fertilization Moore, p 100
The toes are beginning to separate. About day 52 after fertilization Moore, p 100
The fingers are free and longer. Days 52-53 after fertilization Moore, p 91
The auricle, or external ear, is visible. Day 54 after fertilization England, p 92
The ankles are present. Day 54 after fertilization England, p 181
The toes are free and longer. Days 54-55 after fertilization Moore, p 91
The major blood vessels of the body take on their final scheme. Day 56 after conception Rugh, p 53
The face appears to be quite human. Day 56 after conception Rugh, p 53
The fingers of both hands are usually found close to the nose. Day 56 after conception Rugh, p 53
Digit separation in the hand is complete. Day 56 Sadler, p 175
All regions of the arms and legs are well-developed, including the toes. Day 56 of development Larsen, p 213
Muscular layers of the stomach, esophagus, and intestines begin to proliferate. Day 56 after conception Rugh, p 53
The primary teeth are at the cap stage. Day 56 after fertilization Larsen, p xii
The embryo has a distinct human appearance. About day 56 after fertilization Moore, p 100
The mouth is present. About day 56 after fertilization Moore, p 100
The lower jaw is developing. About day 56 after fertilization. Moore, p 100
The shoulders are developing. About day 56 after fertilization Moore, p 100
The toes are separated. About day 56 after fertilization Moore, p 100


 


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