Appendix 1
The Chronological Development of The Unborn Child

 

Eighteenth Week

 

Timing

Source
Signs of life (i.e., quickening) are felt by the mother.
18th week after fertilization Moore, p 109
The uterus is formed. 18th week after fertilization Moore, p 113
Canalization of the vagina has begun. 18th week after fertilization Moore, p 113
In nine fetuses studied, there were a median of 57 general movements per hour, which were present during 24% of the observation time. 18th week after conception Roodenburg, p 23
In a study of 9 fetuses, the median number of hand-to-face contacts was 95 per hour. 18th week after conception Roodenbburg, p 33
In a study of 9 fetuses, the median number of head rotations was 6 per hour. 18th week after conception Roodenburg, p 33
Jaw movements include isolated jaw movements, sucking, swallowing, yawning, and tongue movements. In 9 fetuses studied, the median frequency of any kind of jaw movements was 142 per hour. 18th week after conception Roodenburg, p 28 & p 29
In a study of 9 fetuses, the median number of stretches was 6 per hour. 18th week after conception Roodenburg, p 28
Some scalp hair is visible. End of 18th week after fertilization Williams, p 154
The rate of breathing movements was much higher during the second hour after the mother's breakfast or lunch than during the third hour. 20th - 22nd weeks after conception de Vries (1987), p 337
Breathing movements occured most often right after the mother's meal at noon. 20th - 22nd weeks after conception de Vries (1987), p 337
The frequency of breathing movements changes during the day. In a study of 10 fetuses, such movements increased from a median of 2% of the observation time in the morning to 13% n the afternoon, and then fell to 11% in the evening. 20th - 22nd weeks ater conception de Vries (1987), p 337
The fetal heart rate decreases overnight. 20th - 22nd weeks after conception de Vries (1987) p 341
The daily pattern of changes in the fetal heart rate follows the changes in the maternal heart rate. 20th - 22nd weeks after conception de Vries (1987), p 345 & p 346
The frequency of hiccupping changes during the day. In a study of 10 fetuses, the median number of hiccups during 8 AM to 10 AM was 28 per hour, decreasing to 12 per hour during 1 PM to 3 PM. 20th - 22nd weeks after conception de Vries (1987), p 338
The frequency of jaw openings changes during day. In a study of 10 fetuses, th median rate was 51 per hour during 8 AM to 10 AM, increasing to 97 per hour during 1 PM to 3 PM. 20th - 22nd weeks after conception de Vries (1987), p 338
In a study of 10 fetuses, the majority of movements occurred more frequently in the afternoon and evening than in the morning. 20th - 22nd weeks after conception de Vries (1987), p 337
In 9 fetuses studied, the median number of eye movements at 18 weeks after conception was 25 per hour, increasing to 101 per hour at 24 weeks. 18th - 34th weeks after conception Roodenburg, p 28
     


 


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