Presentationsof the face appear to result from the head being bent backwards, instead of forwards upon the chest. They are easily recognized, because the face has so many peculiar parts, as the nose and mouth, for instance, which are altogether unlike what can be felt in any other presentation. In a very early stage the forehead may be taken for the vortex, unless care be used, because itfeelsround and soft like it, but the mistake cannot last long.
The positions in this presentation, as formerly explained, are determined by the chin, and in practice only two are noticed—theright posterior mento iliac, and theleft anterior mento iliac. In the first the chin is on the right side, near the sacrum, and in the second it is on the left side, near the pubes. These answer, it will be seen, to the two principal positions of the head itself. It is generally considered that, though the chin, like the head, may assume other positions, yet it does so in but very few cases, and these presenting no peculiarities which require special notice.
The head descends with the forehead and chin nearly on a level, and the nose occupying the middleof the passage. When fairly in the cavity it rotates, the chin being brought under the pubes, while the back of the head passes into the curve of the sacrum. This is nearly always the process; no matter where the chin may be when the labor commences, it seldom fails to move under the pubes before it concludes. Occasionally it may rotate the other way, and pass into the hollow of the sacrum, while the occiput comes in front, but this is very rare.
The chin is born first, and then follows, below, the forehead, top of the head, and finally the occiput—the face turning upwards towards the mother's abdomen, as each part is successively delivered. When the head is fully born, the body rotates inside the same as in the head presentation, and the delivery concludes in precisely the same way.
PLATE XXXIV.Fig. 1.Fig. 2.presentation of the faceFig. 1.—The chin just passed, in presentation of the face.Fig. 2.—The head full born in presentation of the face.—p.The Pubic bone.—c.The Coccygis.
PLATE XXXIV.
PLATE XXXIV.
Fig. 1.Fig. 2.
Fig. 1.
Fig. 2.
presentation of the face
Fig. 1.—The chin just passed, in presentation of the face.Fig. 2.—The head full born in presentation of the face.—p.The Pubic bone.—c.The Coccygis.
Fig. 1.—The chin just passed, in presentation of the face.
Fig. 2.—The head full born in presentation of the face.—p.The Pubic bone.—c.The Coccygis.
The delivery is precisely the same in all the other positions of the face, excepting that in some of themthe chin has further to rotate before it can pass under the pubes. In all cases however, it may be safely calculated that it will do so, there having been so few instances known in which it has rotated the other way, into the hollow of the sacrum, which is fortunate, for there is always more or less difficulty and danger when it does so.
Sometimes the rotation does not take place at all, but the face descends diagonally, as the head occasionally does.
On the whole presentations of the face are not particularly to be feared, as regards the mother. Some authors even consider them quite favorable, and reckon them only as varieties of the head presentation. Madame Lachapelle states as a principle, that face presentations should always be left to nature. And M. Chailly says he must admit that, in all positions of the face, the labor may terminate spontaneously, excepting when the chin passes behind, in which case it will be protracted, and most likely fatal to the child. The labor is generally a little longer, and more painful, owing to the face not being so perfectly adapted to the passage as the head is; but still it must be regarded as favorable to the mother, though assistance is oftener required than with the head. There is more or less danger to the child however, owing to the head being kept under pressure for an unusual time, which produces congestion. The neck is also forced against the pubic bone, as will be seen by Figs. 1 and 2, Plate XXXIV, and thus the jugular veins are compressed. If there be any delay, it is customary to observe the face closely, after the chin is born; and if it appears from any indications that congestion is taking place, assistance is rendered at once. The face will sometimes becomeso tumefied, and engorged with blood, from this prolonged pressure, that it will not appear natural till several days after birth.
Probably about one child is lost in ten or twelve deliveries in these cases; and if the chin pass behind its death is almost certain.
It was formerly the practice to endeavor to turn the face upwards, when at the superior strait, and so change the presentation to one of the head. This however, is now abandoned, because the attempt is seldom successful, and does not materially improve the condition of things, besides being painful to the mother. The only extra danger with the face presenting is to the child, and this is not removed by the operation; to the mother the face is nearly as favorable as the cranium. In regard to the frequency of face presentations, we find that Madame Lachapelle met with butseventy-twocases infifteen thousand six hundred and fifty-two deliveries.