THIRD SPECIES OF DYSTOCIA.

In describing this species of dystocia, according to the arrangement of Professor NaegelÉ, which we have adopted, it will be necessary to observe that serious obstructions to the passage of the child is seldom produced by it, although, at the same time, many slight derangements in the progress of labour are liable to result, which demand the care of the practitioner.

The membranes when too thick or tough (Merriman’s Synopsis, p. 217,) may retard the labour occasionally, especially during the second stage, when instead of bursting and allowing the uterus to contract more powerfully upon the child by the evacuation of the liquor amnii, they are pushed down into the vagina, forming a large conical sac, which may even protrude externally. We doubt much, however, if the non-rupture of the membranes at the proper time during labour is of itself sufficient to retard its progress, for it is frequently observed that the head will, nevertheless, advance rapidly and even be born covered by the protruded membranes. Where labour is rendered tedious by the unusual strength of the membranes, it is generally connected with considerable distention of the uterus from liquor amnii; in which case the bag of waters is so spherical that it will not descend readily into the vagina, even although the os uteri is fully dilated, and, therefore, prevents the advance of the head: to this we shall recur immediately. So long as there is no undue accumulation of liquor amnii, we may safely allow the membranes to descend to the os externum before we rupture them. In former times a variety of instruments were employed for this purpose, many of which were dangerous, and all unnecessary, the finger being in most cases sufficient. The most effectual way of doing this is to press the thumb and middle finger upon the membranes during a pain and thus increase their tension, whilst the point of the fore-finger is pushed against them: scratching them with the nail during a pain will be sufficient when they are higher up the vagina.

Premature rupture of the membranes. More frequently the membranes rupture too soon, that is, before the os uteri is fully dilated: this may arise from their being too thin, a condition, however, which it is not very easy to prove: in most instances, it is observed where the uterus is but moderately distended, and where it has that oval or pyriform shape which we have already pointed out as being best adapted for acting efficiently upon the os uteri. This, perhaps, is one reason, why too early rupture of the membranes so frequently occurs in primiparÆ; and this may be one cause, among many others, why first labours are generally so much more tedious and severe. The membranes may also be prematurely ruptured by violent exertions, coughing, sneezing, vomiting, &c. by straining immoderately and too soon, by rough and awkward examination, &c. Where this is the case, the patient should preserve the horizontal posture, and keep as quiet as she can until the os uteri has dilated sufficiently and allowed the head to advance.

Liquor amnii. Where the uterus is distended by an unusual quantity of liquor amnii, its contractile power is necessarily much impaired; and until the quantity of its contents be somewhat diminished, the progress of the labour will be more or less retarded. The average quantity of liquor amnii at the full period of pregnancy is about eight ounces; but it frequently exceeds this very considerably, occasionally amounting to several pints or even quarts. The causes of this extraordinary accumulation are still but little known. “M. Mercier has, in some cases, attributed it to an inflammatory condition of the amnion, the foetal surface of this membrane being stated to have been partially coated with false membrane, and the amnion itself crowded with blood-vessels of a rose colour:” in another case “about a quarter of the foetal surface of the amnion was inflamed, being of a deep red colour and double the natural thickness.”[117] The results of Dr. R. Lee’s observations, after having paid a good deal of attention to the subject, do not tend to confirm this view: he has described six cases of unusual accumulation of the liquor amnii, in one amounting actually to sixteen pints. In five of them “there existed with dropsy of the amnion some malformed or diseased condition of the foetus or its involucra, which rendered it incapable of supporting life subsequent to birth.” In two only of the preceding cases was “the formation of an excessive quantity of liquor amnii accompanied with inflammatory and dropsical symptoms in the mother; and in none did the amnion, where an opportunity occurred for making an examination, exhibit those morbid appearances produced by inflammation, which M. Mercier has described, and which led him to infer that inflammation of the amnion is the essential cause of the disease.” (Lee, op. cit.) Dr. Merriman has given a similar opinion, and states, that “when the embryo or foetus is diseased, the liquor amnii is sometimes immense in quantity. I once saw at least two gallons evacuated from the uterus: the child was monstrously formed and much diseased.”[118]

In these cases the size and globular form of the uterus, the tenseness of its parietes, the more or less distinct feel of fluctuation, the absence of the child’s movements and of any prominences arising from the projecting portions of its body, the rapid increase which has been observed in the size of the abdomen, the pain in different parts of the uterus, especially in the groins and pelvis, the oedema or anasarca of the lower extremities, serve to mark this condition. On examination per vaginam we also feel the inferior segment of the uterus much expanded, the cervix probably shorter than might be expected for the period of pregnancy; the ballottement is unusually free and distinct. In some instances the patient has suffered so much, either from the effects of the retarded circulation in the lower extremities, or from the impeded respiration as to require the membranes to be punctured in order to reduce the size of the uterus. The child is usually born dead where the accumulation has gone to so great an extent: in the three cases recorded by La Motte, it was dead before birth in the first two, and died immediately after birth in the third. Many of these cases, which have been complicated with disease or malformation of the foetus, have appeared to arise from a syphilitic taint; but in others, of more common occurrence, where there was merely an unusually large quantity of liquor amnii without any disease either of the mother or her child, the cause must still remain a matter of uncertainty. This latter condition is mostly seen in women who have been frequently pregnant; the os uteri in them is generally yielding, and when once it has attained its full degree of dilatation, we may safely rupture the membranes and thus expedite labour considerably.

There being an unusually small quantity of liquor amnii can scarcely operate as an obstruction to labour, except where the membranes have been prematurely ruptured.

The umbilical cord may obstruct labour, by either being too short, or rendered so from being twisted round some part of the child. Its length varies very considerably. Although we have stated it to average about eighteen or twenty inches,[119] we have met with extreme deviations both within as well as beyond this medium length. The shortest cord which we know of occurred some years ago at the General Lying-in Hospital, “where, after two or three violent pains, the child was suddenly and forcibly expelled the cord was found ruptured at about two inches from the navel of the child, which cried stoutly. After removing the child the matron sought for the other end of the funis, but could not find it; she examined per vaginam but could not feel it; and on introducing her hand into the uterus, found the placenta with the remains of the cord ruptured at its very insertion; so that in this case the cord could not have been much more than two inches long.” (Printed Lectures in Renshaw’s Lond. Med. and Surg. Journ. May 1835, p. 426.)

We quite agree with Professor NaegelÉ, that unusual shortness of the cord can rarely if ever retard labour; and that where the cord really produces an impediment to its progress, it is from being twisted round the neck, or some other part of the child. (Lehrbuch, 2d ed. p. 289.) This generally arises from its unusual length, and from its having formed several coils around the child: we have met with it forty-eight inches long, and twisted four times round the child’s neck; but Baudelocque mentions a case where it actually measured fifty-seven inches, “forming seven turns round the child’s neck.” (Heath’s Transl. vol. i. § 516.) Mauriceau has given an instance (Obs. 401.,) where the cord had “longueur d’une aune et un tiers de notre mesure de Paris:” which, converted into English measure, amounts to somewhat more than sixty-one inches.

Although nothing is of more common occurrence than the cord being twisted once or twice round the child, it nevertheless, happens, but very rarely, that its advance is thereby obstructed. In a case of this sort, the labour usually commences quite favourably; the os uteri dilates, and the head advances to a certain extent, beyond which it makes no other farther progress; the uterine contractions are attended with much pain in the fundus, during which the head advances somewhat, but retires again during the intervals. Where the head is already near the os externum, this may be easily attributed to the elasticity of the soft parts, until the delay which takes place to the farther progress of the labour warns the practitioner that something more than ordinary is the cause. But where this takes place, and the head is still in the pelvic cavity; where at the same time, although it refuses to advance, it is quite moveable, and allows the finger to be passed freely round it; where any attempt to extract it with the forceps has not only met with great opposition, but has greatly aggravated the sense of painful dragging in the upper parts of the uterus there will be pretty certain evidence of the cord being either too short, or, what is most probable, of its being twisted round the child. In each of the three cases recorded by La Motte, the head had descended to the os externum; whereas, in two others described by Burton, it was evidently much higher up: he ruptured the cord in both instances; La Motte succeeded in cutting the cord with a pair of scissors in one case, in another he appears to have separated the placenta, and in the other to have delivered by little else than force. Where upon introducing the hand we find it impossible to undo the coil of the funis, we should endeavour to slip it first over one and then the other shoulder, as we have recommended under the more ordinary circumstances: should this fail, we must try to cut it through either by a finger nail slightly notched for the purpose, or by the introduction of a Smellie perforator well guarded.

The cord being twisted round the child’s neck may not only retard labour, it may destroy the child itself by preventing the free return of blood from the head: this may take place some little time before birth, or during the actual process of labour. That suffocation cannot possibly be the cause of death under these circumstances is sufficiently evident.

Knots upon the cord have been mentioned by some authors as a cause of danger to the child shortly before and especially during labour; for the circulation in the umbilical vessels being more or less compressed, the child would either be born dead or in a very weakly state. Experience has, however, shown that these effects have been much over-rated, and that these knots are seldom injurious to the child.[120] Baudelocque has not only met with single, but even triple and very complicated knots tied tightly upon the cord, and yet the child was not only born alive, but remarkably robust and healthy. Circumstances, however, may occur by which the knot is gradually drawn so tight as to destroy the child. Smellie has given a case of this kind; but it is to the late Matthew Saxtorph, of Copenhagen, that we are indebted for an admirable essay on this subject. The result of his observations coincides with those of Baudelocque, viz. that it rarely proves fatal to the child.[121] The manner in which these knots are formed may be easily imagined; when by chance the cord lies in the form of a ring, and the foetus happens to float through it, a noose is made, which, when drawn tight by accident, forms a knot.

The most favourable time for the formation of such knots is in the earlier months of pregnancy, when the quantity of liquor amnii, in proportion to the bulk of the foetus, is so much greater than at an after period, and when its movements are consequently less impeded. The circulation in the knot will be obstructed in proportion as the knot is drawn closer: if it be merely somewhat impeded, the vessels on each side of the knot will be distended and varicose, and the cord itself, where it forms the knot, from the constant gradual pressure of one fold against the other, will become more or less flattened.[122] We believe that in every case the cord has been of unusual length.

The placenta cannot easily obstruct the birth of the child, although it may render the labour exceedingly dangerous in a great variety of ways: these circumstances will be considered under their respective heads.