Some Causes of Delay in Labour; with Special Reference to the Function of the Cervical Spine of the Fcetus.”

Jones: Delayed Labour 407 Some causes of delay in Labour; with special reference to the Function of the Cervical Spine of the Fcetus.” By JOSEPH JONES, M.D. (Vict.), Leigh, Lancashire. IN an industrial district where, from time immemorial, the bulk of the obstetric work has been in the hands of midwives, it is not Bur- prising that the attention of a medical practitioner should be forcibly directed to the delay which frequently occurs in labour. For he is chiefly called to tardy and difficult cases, his attendance on normal confinements being limited to those occurring amongst people in better circumstances, and to a few primiparae in the working classes. My own experience of these urgent calls is that most of them are instances of delay without any grave anomaly in the size or relations of the parts concerned, the difficulties having been due to the follow- ing causes in the 383 cases recorded up to the time of writing :- Cancer of the cervix 1, tumour in the pouch of Douglas 1, brow presentations 1, face presentations 2, unfavourable positions of head above brim of pelvis 5, large size of child 7, contracted pelvis 7, antepartum bmorrhage 8, transverse positions and prolapse of hand 18, occipito-posterior positions of foetal head 45, rigor mortis in the fetus 3, anomalies of the cord 10, and other causes 125. To a large extent there is no doubt that protracted labour is a condition of modern creation. At all times the propriety of artificial aid has been a matter of the nice judging of probabilities, operation being indicated when its risks are less than those of refraining; and with an increased knowledge of the mechanism of labour, a greater skill in operative measures, the invention of better instruments, and the diminution of pain and danger brought about by the introduction of anaesthetics and antiseptics, the drawbacks of operative interference have been lessened. Therefore it is often practised nowadays at an earlier moment than would have been legitimate in times past. This has shortened the period allowed to a “ natural’’ labour, and to this extent, “protraction” is a modern creation. But it must be admitted that before obstetrics was a science at all there were frequent instances of protraction which caused exceptionally great pain and ’Based upon a thesis presented to the Victoria University of Manchester for the degree of M.D., for which a gold medal was awarded to the author. Journal of Obstetrics and Gpcecology danger, and these could not fail to be recognized as abnormal by even the most patient and those most ignorant of operative relief. The accounts of the death of Rachel in bearing Benjamin, and of the birth of Scipio Africanus, Claudius and Julius Czesar, and Macduff, clearly indicate that difficult labour was not unknown in other days. Opinions are neither definite nor unanimous as to what constitutes a “ normal ” labour. When certain unmistakable conditions are excluded, such as unfavourable presentations, there still remains a large number of instances where the question of the labour being either “ normal ” or “ protracted ” has to be decided by the personal judgement of the accoucheur. If he be skilful in operating, he may consider interference desir- able at an earlier stage than if he be averse from operation or if his experience of it be unfavourable. If he be sympathetic with the woman in her sufferings, or impatient of delay, he may note signs of exhaustion earlier than a man more callous or more patient would. To some extent this personal factor must always esist, as it necessarily makes itself felt in all branches of medicine and surgery. But it may be kept within due bounds by a consideration of the time allowed by well-known obstetricians, so far as their works are published. A reference to twenty of the best known books on midwifery published since 1726 shows a general agreement that a prirnipara may be in natural labour for about 24 hours, with a second stage of about 2 hours; and that a subsequent labour ought to be over in half the time. The longest time regarded as a normal period for the second stage is 8 hours (Churchill): the shortest, 10 to 15 minutes for a multipara (Jellett). Many do not time the second stage separately. Sinclair says “there should be no delay in the second stage.” La Motte regards labour as normal, irrespective of its duration and “whatever part of the child presents, if it comes without help.” Meadows and Playfair state no limit, because, as they point out, to do so would imply that operative interference should always take place at that time (whether needed or not), and not earlier however urgently it may be required. My own practice in the absence of indications to the contraxy has been to allow as much time as necessary to the first stage ; and in the second stage, to consider, as a rule, no case protracted until it has been a full hour without any advance of the presenting part. Thus, if there is not a complete standstill, more than the two hours may be allowed to pass in the second stage without classifying it as protracted. ‘‘ Protraction ” is not regarded as synonymous with “ requiring operative aid.” Some patients are saved from protraction by timely (if Jones : Delayed A&QW 409 temporary) interference, whilst others are left to nature, in spite of much delay. But on the other hand a case is considered protracted immediately that any remediable opposition prevents a few pains from driving the fetus onward. Amongst the causes of protracted or difficult labour, there are three that appear to me to have received inadequate notice in existing works, namely :- I. Anomalous conditions of the umbilical cord, 11. Cadaveric rigidity in the fetus, and 111. Failure of the movement of “ extension of the head ” in cases of vertex presentation. I purpose to devote a separate section to each of these subjects. The first is mentioned in all obstetric text-books ; but few of those explain the mechanism of virtual shortening, and none aa far as I am aware, has described the “Blackwall hitch” action of the cord in arresting the progress of the fetus. Cadaveric rigidity is unnoticed by most writers. It is easily over- looked unless it be expected, and probably it is often left unrecorded when observed in practice. The third section is the one that I consider of the most con- sequence. It does not appear to have been recognized generally that in the first and second cranial positions of vertex presentation there is a distinct and separate movement between flexion of the head and its extension, in addition, of courae, to internal rotation which “ ii3 generally also still proceeding” (Galabin). I shall attempt to show :- (1) that there must necessarily be, and is, such an intermediate movement ; (2) that it is an extension of the cervical spine of the fetus; (3) that it makes true extension of the head possible, where as a rule it would not occur without it ; (4) that the extension of the cervical spine is accompanied by a “mechanical advantage” in the transmission of power to the head, which is progressively greater as the spinal extension increases ; (5) that the movement is therefore most easily arrested at its incep- tion ; and more able to continue, the farther it has progressed ; (6) that it is about the beginning of this movement that delay is apt to occur in otherwise normal cases, and that when the movement ha&begun the patient’s progress is more rapid ; and (’7) the appropriate treatment. 410 Journai of Obstetrics and ~9&@co~Ogy I. ANOMALOUSCONDITIONS OF THE UMBILICALCORD. In so far as the umbilical cord has any mechanical effect on the process of labour, its anomalies are best considered under the heads of length and of arrangement. 1. Length. This is of little present interest. An excessive length of the cord seldom causes trouble. Real shortness is rare but its effects are obvious. The short cord of some of the lower animals is not a source of the same amount of danger, as the conditions of their birth are different. 2. Amzngement. Practically, all the mechanical hindrance exer- cised by the cord is in connection with the manner of its disposal. It may be anomalous in respect of (a) prolapse, (b) twisting, (c) knots, and (d) loops. Discussion of the first three of these is omitted. Loops around the child are the most important anomalous conditions of the cord and are described by all writers. They are formed either by the child passing partly through a loop in a slack cord, or by rotations of the fcetus causing the cord to coil around some part of its body, usually the neck. If the virtual shortening thus brought about be considerable, it causes great delay in labour by its dragging effect. I have noticed this in seven cases where no other apparent cause for the delay existed. (Nos. 28, 54, 114, 120, 197, 285, 321.) Indirectly also it retards labour in the later part of the second stage, inasmuch as it diminishes the head's pressure on the perineum or pulls it away altogether, whereby the normal reflex stimulus to the uterus is wanting. But the same effect may be produced when the cord only passes around the neck once, if the placental end be the shorter and so arranged that it compresses the loop on the fcetus causing the loop to jam. This is the principle of the Blackwall hitch (fig.

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