316 UNNATURA.L EUTOCIA. 



pelvic presentations than in those in which the vertex descends first. 

 At the Paris Maternite, out of eight hundred and four children expel- 

 led in this manner, only five hundred and eighty-one were born liv- 

 ing, whilst out of a sum total of twenty thousand six liundred and 

 ninety-eight vertex presentations only six hundred and sixty-eight 

 were still-born. 



768. After the rupture of the membranes, the pelvic extremity of 

 the foetus never presents the same evenness, the same resistance, or 

 the same rounded form as the head, to the openings of the pelvis; 

 it consequently acts to much less advantage on the cervix to finish 

 its dilatation. When the head presents, the uterine contractions act 

 upon it, through the medium of the spinal column, as upon a solid 

 body; while the pelvic extremity, on the contrary, being soft,>up- 

 ple, and flexible, yields, and is in some measure crushed down. In 

 vertex presentations the most voluminous part, that which is best 

 calculated to bear all sorts of pressure, escapes first. In pelvic pre- 

 sentations, on the contrary, the point of the cone advances first, so that 

 the foetus progresses more slowly in proportion as the labor advances. 

 In the former case the remaining parts of the child are delivered 

 immediately after the abdomen, and neither the thorax, nor abdo- 

 men are in danger of suffering any injurious compression; in the 

 latter, the belly and the thorax being obliged to overcome the re- 

 sistance of the cervix, can rarely support such a degree of pressure 

 beyond a few minutes without the greatest danger; the liver and 

 other viscera of the abdomen must react upon the great vessels; 

 the circulation in the cord, which is pressed against the breast, and 

 the action of the heart, cannot but be very much impeded, if not ab- 

 solutely suspended. In delivery by the head, the spine represents a 

 long handle of a lever, to which the womb applies itself forcibly, 

 until the termination of the labor; in presentations of the pelvic ex- 

 tremity, before the head has completely passed through the superior 

 strait, it is in a great measure beyond the influence of the uterine con- 

 tractions; at the very moment where the greatest amount of uterine 

 power is wanted, all the benefits of it are lost. Finally, the pressure 

 sustained by the parts, in succession, from below upwards, necessarily 

 drives the blood up towards the head, and determines that state of 

 congestion so often met with in children that are dehvered footling, 

 and which Osiander and M. Flamant erroneously attributed to the 

 action of cold air upon the child's body previously to the delivery of 

 its head.* 



* The view taken here of the causes of death which so frequently operate ef- 

 fectually on the foetus, in pelvic presentations, omits one of tlie most considera- 



