A System of Midwifery

by Edward Rigby

Several reasons have been assigned why the straining pains should come on at this stage. It cannot be owing to the pressure of the head upon the parts of the pelvis, as has been supposed and especially the rectum, thus producing the sensation of a violent desire to evacuate the bowels, because, in almost every case of first labour, the head for several days before the actual commencement of labour is sufficiently deep in the pelvis to produce these effects. It evidently arises from a sympathetic connexion “between the os uteri and vagina on the one hand, and the abdominal and other muscles on the other. We see this connexion most distinctly in those difficult labours where the head is pushed down deeply in the pelvis even to the very outlet, and where the os uteri which is but little dilated is protruded before it. In such cases we never see the really powerful and continued action of the abdominal muscles excited, let the head press never so forcibly upon the rectum; but as soon as the os uteri (perhaps after much suffering) has retracted over the head, the whole auxiliary action of the abdominal muscles commences.” (Ibid. vol. ii. p. 467.)

There is the same relation between these muscles and the vagina, as there is between them and the rectum: the moment the vagina becomes distended, it begins to contract upon the distending body, and like the rectum excites them to strong and involuntary action. The tenesmus of dysentery is a sympathetic action of the same nature; the rectum is highly irritated by the acrid nature of its contents, and excites an irresistible disposition to bear down. The patient wishes for the next pain and yet she dreads it, from the suffering it creates, and the tremendous effort which it compels her to make; the pulse is quicker, and is not only so during the intervals, but undergoes a greater increase of rapidity during the pains themselves than in the first stage; the face becomes red, swollen, and bathed in perspiration; the breath is hurried; the lips are apart; the eyes are wild; every thing betokens a state of the highest excitement. When a pain comes on, she catches hold of whatever she can reach, plants her feet upon any thing which is firm, and, by thus fixing her extremities, she is enabled to bear down with greater power and effect. During the struggle the face often changes its expression surprisingly, so much so, that even her own attendants would scarcely recognise her.

Dilatation of the perineum. As pain succeeds pain, gradually increasing both in force as well as duration, the head descends along the vagina, and begins to press against the perineum; the rectum becomes flattened; the sphincter ani dilated, and therefore any fæcal matter which may have been lodging there is unavoidably expelled; the anterior wall of the rectum is pressed close against the anus, and where the pressure is very great, even protrudes somewhat through it; the hæmorrhoidal veins are frequently much distended, and form a roll of cushiony swelling around the anus. A small quantity of liquor amnii dribbles away from time to time, but is neither during a pain, nor during the absence of a pain, for in the former case the pressure of the head acts as a plug and prevents its escape, and in the latter there is no uterine contraction present to expel it: the liquor amnii dribbles away only at the moment when a pain is coming on or going off.

Expulsion of the child. As the head descends farther it begins to press more powerfully on the perineum, and during each pain pushes it out like a large ball; and then, as a contraction goes off, and the resiliency of the soft parts regain their superiority, it retires again. The breadth of the perineum (viz. from the anus to the vulva) increases, whilst it diminishes considerably in thickness, especially towards its anterior margin. Whilst passing through the inferior aperture or outlet of the pelvis, the head advances more or less forwards under the pubic arch, and begins to distend the os externum; during a pain it separates the labia, and protrudes between them, and again retires as the pain goes off; a larger and larger portion of the head gradually forces itself through the os externum as this dilates; the perineum becomes still thinner, so that at length it is scarcely thicker than parchment. When more of the head has passed through, it does not now recede when the pain goes off; the os externum and perineum are at their greatest distension, for the largest diameter of the head, which is presented to the os externum is now encircled by it; the next pain brings the head into the world.

This is the moment of greatest pain, and the patient is frequently quite wild and frantic with suffering; it approaches to a species of insanity, and shows itself in the most quiet and gentle dispositions. The laws in Germany have made great allowances for any act of violence committed during these moments of phrenzy, and wisely and mercifully consider that the patient at the time was labouring under a species of temporary insanity. Even the act of child-murder, when satisfactorily proved to have taken place at this moment, is treated with considerable leniency. This state of mind is sometimes manifested in a slighter degree by actions and words so contrary to the general habit and nature of the patient, as to prove that she could not have been under the proper control of her reason at the moment. It is a question how far this state of mind may arise from intense suffering, or how far the circulation of the brain may be affected by the pressure which is exerted upon the abdominal viscera.

A short cessation of pain succeeds the birth of the head. The violent distension of the os externum has ceased for a time, and the patient feels comparatively easy; but in the course of a few minutes the pains return as before, although not quite so severe: first, the shoulder, which is turned forwards, passes under the pubic arch, followed by the other which sweeps over the perineum. The rest of the child is expelled with comparative ease, and as soon as its pelvis has passed through the os externum, a gush of the remaining liquor amnii, which had been retained in the upper portions of the uterus, follows; the whole abdomen instantly sinks and becomes flaccid, while the uterus contracts into a firm globe upon the placenta, which is shortly to be expelled. A most delightful and perfect calm succeeds, and the sense of freedom from suffering, and joy for the termination of her trial, are expressed in the liveliest terms of gratitude.

Third stage.—Expulsion of the placenta. The period between the birth of the child and expulsion of the placenta varies considerably. Sometimes it follows the child very rapidly, so that, apparently, they are both expelled by the same effort of uterine action; at others, the interval is more considerable. There is generally an interval of ten or fifteen minutes, and then pains of a totally different character make their appearance: these are supposed to denote the separation of the placenta from the uterus, and, from their being usually attended with discharge of more or less blood, have been termed dolores cruenti by many of the foreign writers. The expulsion of the placenta is attended with little or no suffering; it descends into the vagina inverted, i. e. with its fœtal or amniotic surface turned outwards: whether or not this is produced by pulling at the cord is perhaps a question.

Twins. If there be twins, the placenta of the first child is seldom expelled until after the birth of the second child. The membranes of the second ovum become distended with liquor amnii, project into the vagina and burst as in a common single labour; the passages have been sufficiently dilated and prepared by the birth of the first child, so that, when the uterus begins to contract, the expulsion of the second will be readily and easily effected. The uterus may resume its efforts for this purpose in twenty minutes after the birth of the first child, or it may remain quiescent for several hours without at all disturbing the regular and natural course of the process which will be precisely the same as in the previous case.

The placentæ of twins are usually expelled together, forming one large placentary mass; their vessels, however, are distinct from each other, so that with care one placenta can be peeled away from the other. In other cases, they are separated from each other by an intervening space of membranes; and in one rare instance of triplet placentæ the umbilical arteries of two placentæ anastomosed with each other, before dividing into smaller branches.

Upon the expulsion of the placenta, the uterus, being now emptied of its contents, contracts into a firm hard ball, which may be felt behind the symphysis pubes, or sometimes a little to one side, of about the size of a full grown fœtal head. This state of hard contraction gradually disappears, and a discharge of blood called lochia follows, which having continued for a few days becomes colourless, and at length ceases altogether. For a description of the changes which the uterus and passages undergo in returning to their former condition as in the unimpregnated state, we refer to the chapter on the Female Organs of Generation.