PART III.
EUTOCIA, OR NATURAL PARTURITION.
CHAPTER I.
STAGES OF LABOUR.
Preparatory stage.—Precursory symptoms.—First contractions.—Action of the pains.—Auscultation during the pains.—Effect of the pains upon the pulse.—Symptoms to be observed during and between the pains.—Character of a true pain.—Formation of the bag of liquor amnii.—Rigour at the end of the first stage.—Show.—Duration of the first stage.—Description of the second stage.—Straining pains.—Dilatation of the perineum.—Expulsion of the child.—Third stage.—Expulsion of the placenta.—Twins.
Parturition may be divided into two great orders, Eutocia and Dystocia, the one signifying natural labour which follows a favourable course both for the mother and her child; the other signifying faulty or irregular labour, the course of which is unfavourable.
We may define eutocia to be the safe expulsion of the mature fœtus and its secundines by the natural powers destined for that purpose. No function exhibits such infinite varieties, within the limits of health and safety to the mother and her offspring, as that of parturition; no two labours, even in the same individual are exactly alike; still, however, the great objects of the process will be the same, viz. 1st. the preparation of the passages and the fœtus for its expulsion; 2dly, the expulsion of the fœtus; and 3dly, the expulsion of the placenta and membranes.
That we may form a clearer and more comprehensive view of this process, labour has usually been divided into stages or periods, marked by the changes just now alluded to: hence it is generally said to consist of three stages; the first, or preparatory stage, commencing with the first perceptible contractions of the uterus, and terminating in the full dilatation of the os uteri; the second, or stage of expulsion, terminating with the birth of the child; and the third, consisting of the expulsion of the placenta.
Preparatory stage.—Precursory symptoms. For some time before the commencement of actual labour, a variety of changes are taking place which must be looked upon as the precursors of this process: during the last weeks of pregnancy, nature appears, as it were, to be preparing for the great change which is at hand, and to be making such arrangements as shall enable it to be completed with the least possible danger both for the mother and her child.
One of the earliest warnings which we have of approaching labour is an alteration in the form of the abdominal tumour; the cervix uteri has by this time (especially in primiparæ) entirely disappeared; the presenting part of the child has therefore descended to the lowest part of the uterus; the fundus has sunk lower and more forwards; and from the diaphragm being enabled to act with greater freedom, the respiration is performed with more ease and comfort to the patient; she therefore feels more capable of moving about, and is in better health and spirits than for some time previously. Upon examination per vaginam, the head will be found deep in the cavity of the pelvis, covered by the lower and anterior segment of the uterus; the os uteri is still closed, and situated in the upper part of the hollow of the sacrum, forming merely a small circular depression. In women who have already had children, a portion of the cervix uteri is still remaining; it is thick and bulky; and in some cases, where the uterus has been greatly distended in several successive pregnancies, it is nearly as long as in the unimpregnated state; the os tincæ or os uteri externum is open, its edge irregular from former labours; the upper extremity of the canal of the cervix is contracted, and forms the os uteri internum; it has been closed during the greater part of pregnancy, but usually is now sufficiently open to admit the finger; the os uteri is neither so high up nor so far backwards in the pelvis as in primiparæ, and is reached with greater ease; whereas, the head of the child, instead of being felt in the cavity of the pelvis, generally remains at the brim until labour is more advanced.