The Unborn Child

Based on an Address delivered to the Royal Medical Society, on Friday, 13th January. 1961. Just as the clinical picture of any pregnancy changes from week to week so the picture of obstetric practice as a whole is changing. As childbearing and childbirth have become safer for the mother more and more attention has been directed to her unborn child. The foetus and its placenta, however are remote when compared with the mother and therefore can often only be studied indirectly. Copyright Royal Medical Society. All rights reserved. The copyright is retained by the author and the Royal Medical Society, except where explicitly otherwise stated. Scans have been produced by the Digital Imaging Unit at Edinburgh University Library. Res Medica is supported by the University of Edinburgh’s Journal Hosting Service: http://journals.ed.ac.uk ISSN: 2051-7580 (Online) ISSN: 0482-3206 (Print) Res Medica is published by the Royal Medical Society, 5/5 Bristo Square, Edinburgh, EH8 9AL Res Medica, Autumn 1961, 3(1): 33-38 doi: 10.2218/resmedica.v3i1.375


THE UNBORN CHILD
Professor of Obstetrics and Gynaecology, University of Sheffield.
Based on an Address delivered to the Royal Medical Society, on Friday, 13th January.1961.
Just as the c1inical picture of any pregnancy changes from week to week so the picture of obstetric practice as a whole is changing.As childbearing and childbirth have become safer for the mother more and more attention has been directed to her unborn child.The foetus and its placenta, however arc remote when compared with the mother and therefore can often only be studied indirectly.

The Examination of the Foetus
The methods of examination of the foetus in late pregnancy are mentioned first.W e can palpate it, estimate its size however roughly, recognise movements, look at its shadow on an X-ray film and over a period of time estimate its growth.Also we can listen to the foetal heart sounds, but listening is one thing and understanding what we hear is another.It is difficult to interpret foetal heart irregularities and observed changes may mean different things in different cases.The ordinary methods of listening to the foetal heart a r e good enough in most cases, but for some, rather more precise techniques should be employed.In cases of special difficulty the foetal heart can be monitored with a cardiophone.This apparatus is expensive but provides a clear and continuous record of the foetal heart rate, though the sounds differ from those heard with the ordinary stethoscope.
As a result of this monitoring of the foetal heart in special cases we have noted changes in the rate, not otherwise detectable, which we have interpreted as meaning that the child was in clanger.Some of these changes have been translated into graphic records.Figure 1 demonstrates intermittent slowing of the foetal heart rate in a case of severe placental insufficiency.The routine interrupted listening had revealed no abnormality but continuous recording over many hours showed that from time to time the heart rate dropped alarmingly.After observation for 24 hours it was decided to deliver the baby by Caesarean Section despite its tiny size because it was thought that otherwise it would die in utero.This was done and as we suspected, the placenta was small and extensively infareted.The child did not survive In another case, illustrated in Figure 2, a patient who had lost her previous child was admitted because she was a few days beyond the expected date of delivery.Induction of labour was decided on and an attempt was made to rupture the forewaters, but no liquor was obtained.The child was small and the foetal heart in this case was also monitored.For nearly an hour after the J attempted artificial rupture of the membranes there was no suggestion of foetal heart irregularity.Then quite suddenly and rather unexpectedly the rate became grossly irregular, occasionally falling tu So and B lie ing the foetus to be in danger.we performed Caesarean Section ; this child sur d .particular question \\'hich we were not able to was why the foetal heart should have shown this gross slowing and irregularity, and why in a case which was otherwise perfectly normal at 41 weeks was there n o liquor in the uterus.
Attention to the foetus is very important and so is attention to the placenta hut this remarkable structure is even more difficult to study : as there is n o direct method of examination, iudircct methods have to be relied o n .The placenta normally has ample reserve for supplying the needs of the growing foetus.Sometimes, however, diminishing vascularity and increasing fibrosis can materially reduce this reserve until the amount of functioning tissue is barely sufficient or is insufficient for the foetal requirements; interference with nutrition will then retard foetal growth and the child may just survive or succumb during labour, or in cases of severe placental insufficiency, die in utero some time before term.Sometimes the placenta is too small to nourish a normal sized foetus and the placental reserve gets used up before term.

Placental Jusuffieiency
Placental insufficiency though as old as midwifery itself is rather a new expression and like other new expressions has different shades of meaning.The failure of function can occur quickly, e.g. in accidental haemorrhage or more slowly as in pregnancy toxaemia ; also the failure may occur at different stages of pregnancy.Placental insufficiency is most often seen in association with hypertension or toxaemia of pregnancy or both, but it is not an invariable complication of even the more severe examples of these diseases and it may occur in the absence of t h e s e conditions.'T'he problem is how to recognise in any particular case if there is sufficic.:ntplacental damage to affect the foetus.In the Ante-natal pc.:riod.the recognition of a small child which fails to grow shows that it is in clanger, and the estimate of the degree to which its growth is affected is the first measure of how great this danger is.

Hormonal Excretion in Pregnancy
Additional information enabling a better estimate of placental function would be of undoubted benefit in such cases.To this end we have in Sheffield been studying the hormonal excretion in pregnancy.and particularly the excretion of pregnanediol, the principal excretion product of progesterone.
During pregnancy there is a steady increase in t h e urinary output of pregnanediol until about the 35th or 36th week when the rising curve of excretion flattens off and falls slightly as term approachc.:s(Fig. 3).
Our early work (Russdl, Coyle and Dcwhurst 1957) indicated that in cases in which there was placental damage, the levels of excretion were below normal and therefore that knowledge of the levels of excretion should prove helpful in practice.
More recently we reported (Russdl, Dewhurst and Blakey 196o) a study of the pregnanediol excretion in a group of 58 patients in whom we had diagnosed on clinical evidence placental insufficiency or in whom there was the possibility that it might be present.Most of the patients either suffered from hypertension or pre-eclampsia or gave a history of a previous still-birth believed to be due to placental insufficiency ; a few patients had no such associated abnormalities. W

Obstetrics and Gynaecology o f t h e B r i t i s h Commonw e a l t h .
13 cases supporting our clinical impression ; in one case low readings suggested some placental damage.Tn Group 3, readings within the normal range but below the normal average showed reasonable placental function in 10 cases; low readings showed placental insufficiency in 15 cases, while in 3 cases equivocal results were o b t a i n e d 28 Taking all 3 groups together there were 30 cases with low readings.In all of these there was evidence of enough placental damage to affect the child ; 11 babies were still-born and 2 died in the neo-natal period ; all the babies were below average weight for the stage of pregnancy.The placentae were small and in addition showed evidence of infarction which was sometimes very severe.By contrast, in the 25 cases with normal values, apart from one unexplained death, the weights of the babies and of the placentae were normal.
The pregnanediol assay provided us therefore with confirmation or correction of our clinical di<1gnosis, or the only reliable evidence of the state of the UNBORN CHILD ..,..., ) placenta when a clinical diagnosis could not be made: mor the amount by which the readings fell below the normal range indicated the of the placental damage and the urgency of the problem as it affected the child.
The treatment of an indi idual case was not based on the pregnanediol readings alone, but on all aspects of the case.The assay was helpful none the less, for although the mode of the d y decided almost exclusively clinical grounds, the timing of induction or operation \\'as simplified by our greater knowledge of the degree of placental damage present.
a number of cases.the knowledge that there was a degree: of placental damage made it clear that if the child was to be d ry was necessary although the child was tiny and the duration of pregnancy perhaps not more than weeks; in such cases without this additional knowledge our inclination ccrtainly been to delay interference: with the likely death of the in utero.In other instances we were encouraged by good readings to with hold interference until the child was more mature or altogether: in still others, a number of late pregnancy readings falling just below the normal range suggested that it would be unwise to allow the patient to go The assay requires accuracy and precision if reliance is to be placed on the result obtained.A 24 hour specimen of urine is needed and must be collected exactly, and the assay carefully performed.There is some uncontrollable error so second or third specimens should often be assayed.Reliance on the of more than one assay the error of the single assay by the square root of the number of assays.

The
of the Child decided that the foetus is in danger in utero either labour must be induced prematurely or Caesarean Section performed.This choice though superficially straightforward can be most difficult because practice has shown that there is no guarantee that the child will its this is arranged.There is much still to be learnt about normal labour.aspects of natural delivery are good for the child?The means by which the baby negotiates the birth canal may be passed over quickly, the descent and flcxion of the babv's head, the internal rotation, the extension, the restitution and so on are all-important but the slow squeezing of the baby's head and thorax in labour has also to be considered.Is this a hazard separating the robust from the fragile baby?Perhaps the squeezing of the baby's head is a way of showing the baby that life may be hard and that it had better get on with it.The squeezing of the child's thorax in the course of a normal delivery may be an important means by which the chest is cleared of any debris or liquor that may have been inhaled during the practice respirations that we know go on in utero.
These considerations arc important because as an alternative to vaginal delivery we may perform Caesarean Section and in this operation there can be n o comparable pressure on head and thorax.There is seldom any serious difficulty with the robust foetus of good size but the minutiae of the delivery may be of prime importance when the foetus only weighs 3 -4 lbs.or even less.M y impression is that normal labour is preferable to Caesarean Section for the very small foetus but the labour must be normal otherwise different hazards operate ; the closest watch must be maintained at the end of the first and beginning of the second stages because it is then that the foetus is in danger of asphyxia.
Other Hazards to the Unborn Child.
The unborn child may die in utero or it may die after its birth but there arc By C. SCOTT RUSSELL, M.D., F.R.C.S.[Erlin.),F.R.C.O.G.

FIG. 1 .FIG. 2 .
FIG.1.Intermittent slowing of the foetal heart in a case of severe placental insufficiency.
e based our clinical diagnosis of placental insufficiency on the finding By courtesy of T h e Journal of Obstetrics and Gynaecology of t h e British Common-wealth.of a small child which did not grow normally ; on this basis we made a confident diagnosis of placental insufficiency in 16 cases (Group 1) ; in another 34 (Group 2) we considered placental damage was not significant: and in the , ........ .• ...•:.:•=••: