The Matron's Manual of Midwifery, and the Diseases of Women During Pregnancy and in Childbed / Being a Familiar and Practical Treatise, More Especially Intended for the Instruction of Females Themselves, but Adapted Also for Popular Use among Students and Practitioners of Medicine

by Frederick Hollick

PLATE XXX.

Fig. 1.

Fig. 2.

In Fig. 1, the back of the head is nearly under the pubic bone, while the forehead is just passing the external opening below.

In Fig. 2, the back of the head is completely extruded, and also the chin, so that the whole head is now born.—(p. is the pubic bone, in front.)

In Fig. 1 it will be seen how the Os Coccygis, or lowest part of the back bone, (c,) is straitened out, backward, while the head is passing, as I explained before; and in Fig. 2 it has returned again to its natural position.

The reason for this rotation of the head will be obvious on calling to mind the form of the Pelvis and the external opening. On examining Plates IX and X, it will be seen that the longest diameter of the Vulva, or external opening, the antero posterior, is nearly at right angles to the longest diameters of the upper strait, the oblique. Now the longest diameter of the head is adapted to this oblique diameter, on entering the upper strait, as already explained, and it is necessary for it also to be adapted to the longest diameter of the external opening, the anterior posterior when making its exit; but as the two are not parallel the head is compelled to turn, or rotate, in order to pass from one to the other. To accomplish this however, the neck has to be twisted considerably. But when the head is fully delivered, it is immediately straitened again, by the back of the head turning towards the mother's left side, so that its proper relations with the trunk is re-established.

Third Movement, Rotation of the Shoulders.—When the head is delivered the shoulders come next, which also require to turn round a little, to adjust themselves to the long diameter of the lower strait; and as they turn within the Pelvis the head also turns, to correspond, and thus the back of it is brought opposite the middle of the mother's left thigh. Immediately this movement is effected, the shoulders rapidly escape through the external opening, the right one being in front, a little to the left of the symphysis pubes, and the left one behind, a little to the right of the os coccygis. The body then curves upwards, to accommodate itself to the curved axis of the Pelvis, and speedily follows the shoulders.