Rhesus immunisation during pregnancy: the case for antenatal anti-D

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Deaths from rhesus haemolytic disease in England and Wales in 1977: accuracy of records and assessment of anti-D prophylaxis

All the death certificates for deaths in 1977 where haemolytic disease of the newborn (HDN) was the principal, an antecedent, or a contributory cause were obtained from the Office of Population Censuses and Surveys (OPCS). The hospital notes of all 54 of the live-born cases and all of the 101 stillbirths were also obtained. The cause of the death indicated by the notes was compared with the cause and coding on the death certificate. In about a quarter of the cases death was not due to haemolytic disease of any type. The commonest errors arose because the International Classification of Diseases (8th edition) stipulates that hydrops without mention of cause should be coded as HDN and because stillbirths to rhesus-negative mothers tend to be attributed to rhesus HDN automatically. Though deaths from HDN may be overestimated in this way, they are also underestimated because rhesus disease, although mentioned on the certificate, is not selected as the underlying cause, which it may be. These cases were found through multiple coding of all the contributory causes of death, which OPCS performs on a 25% sample of all death certificates for research purposes. These two sources of inaccuracy tend to cancel each other out, but statistics from death certificates give a misleading picture of the efficacy of anti-D prophylaxis because anti-D can never prevent cases which are not in fact due to rhesus HDN. Most of the mothers studied had become immunised before anti-D became available, but in those who could have been treated 75% had not received prophylaxis. As this was a sample of deaths, however, it would not be accurate to extrapolate this high figure to the population at risk. Nevertheless, the organisation of prophylaxis is clearly deficient and should be remedied before providing antenatal anti-D to supplement postnatal treatment.

Spontaneous abortion and fetal abnormality in subsequent pregnancy

In a prospective survey neural tube defects and other congenital abnormalities were studied in the babies born to 510 mothers ascertained during pregnancy. The women were divided into two groups according to the outcome of their immediately preceding pregnancy. Those whose preceding pregnancy had resulted in a spontaneous abortion (256 women) formed the index cases; those in whom the outcome had been a normal baby (254 women) served as controls. There was a highly significant increased number of congenital abnormalities in the index cases. This may possibly be explained by the trophoblastic "rest" hypothesis and suggests that spontaneous abortions are more relevent to congenital abnormalities than has been thought.

Further studies on the industrial melanic moth Biston betularia (L.) in the northwest of the British isles

The frequencies of the three phenotypes carbonaria, insularia and typical of the moth Biston betularia are given for a number of new localities and new samples from old localities in northwest England and the Isle of Man. In one locality (Caldy) the frequency of carbonaria has been decreasing at the rate of 1% per three years since 1959, probably due to the introduction of smokeless zones. Two methods have been used to measure the relative degree of camouflage at Caldy, where the melanic is common, and in the Isle of Man where it is much rarer. In Caldy carbonaria was the better camouflaged, but there was no evidence for this on the Isle of Man. One possible selective agent not previously reported is the bat, P. pipistrellus The rôle of moth movement over land and water is discussed in relation to the maintenance of the polymorphism and the steepness of the clines between North Wales and Liverpool.

Mountain sickness, retinal haemorrhages, and acclimatisation on Mount Everest in 1975

During the 1975 British Everest Expedition, which made the first ascent of the south-west face, observations were made in relation to mountain sickness and the appearance of retinal changes. Two Sherpas with cerebral oedema and one Briton with pulmonary oedema were treated. Retinal haemorrhages occurred in four out of six Britons who were newcomers to altitudes over 6000 m (19 685 ft) but in only two out of 14 Britons who had previously visited these altitudes. Intraocular pressures during ascent to 6000 m were within normal limits. The relevance of the ocular findings to acclimatisation in previous years was examined, the results supporting the hypothesis of a "carry-over" effect from previous visits to high altitude.

Contact lenses at high altitude: experience on Everest south-west face 1975

Five members of the British Everest Expedition 1975 were equipped with hydrogel contact lenses. Some clinical observations are made about the performance of these lenses. Two men were able to use them up to an altitude of 24,000 ft, where the ambient oxygen tension is of the order of 55 mmHg.

Alpha fetoprotein in liver disease in Papua New Guinea

A radioimmunoassay method was used for the detection of alpha fetoprotein (AFP) in the sera of 112 Papua New Guinean patients who had undergone liver biopsy. Sera from 69 normal subjects and 20 hospital patients were also tested. Alpha fetoprotein was found to be elevated above normal levels in many of these subjects, but particularly in those suffering from viral hepatitis, cirrhosis and primary liver cell carcinoma (PLC). The highest values were found in patients with PLC. It is concluded that because of the elevation of AFP values in all these different types of liver disease the RIA test is not of great value in Papua New Guinea, except in the follow-up of some patients with cirrhosis who are at risk of developing PLC and in those who have undergone treatment for PLC.

Ocular bobbing with survival

A case is described of prolonged ocular bobbing with survival after subarachnoid haemorrhage from a pontine arteriovenous malformation. Hitherto, this sign has usually been associated with a rapidly fatal outcome.

Spina bifida and anencephaly: miscarriage as possible cause

In two retrospective Liverpool surveys the domestic, family, dietary, and medical environments of the mothers of children affected by anencephaly or spina bifida, or both (ASB) were examined. None seemed to be of more than minor importance and the findings of others were therefore examined to see if they suggested a major factor. The most promising lead came from the hypothesis that ASB is usually due to an interaction between twin fetuses or between a fetus and residual trophoblastic material from the previous normal pregnancy, particularly when this is of the opposite sex to the propositus. The sex finding was not confirmed. It was noted that hydatidiform moles, like children with ASB, were usually female and that moles and choriocarcinomas on the one hand and children with ASB on the other occurred in mothers of similar ages, but were to some extent reciprocal in geographical incidence. This suggested that trophoblastic disease might be a factor common to all three and if so then one would expect the frequency of miscarriages to be higher immediately before than immediately after the birth of an ASB child, since mole and choriocarcinoma seldom follow a normal pregnancy. An analysis of published data confirmed that this was almost certainly so. Hence residual pathological trophoblastic material from either a previous miscarriage or a co-twin may interact unfavourably with another fetus to produce ASB and this may be the primary cause of the condition. The hypothesis is consistent with the observed lack of concordance in twins, the high incidence in females, the maternal age effect, and the greater prevalence in social classes IV and V.

The genetics of the mimetic butterfly Hypolimnas bolina (L.)

Hypolimnas bolina is a Nymphalid butterfly having a west to east distribution from Madagascar to Easter Island, and a north to south one from Japan to Australasia. It is highly migratory in some areas. In much of the western part of its range the female is both monomorphic and a mimic of Euploea. Further east it is frequently polymorphic with the majority of the forms being non-mimetic. The polymorphism is sex-limited to the female and controlled by two unlinked loci, one with two allelomorphs, E and e, determining the extent of the dark pigmentation, the other with three allelomorphs, P, Pn and p, determining the presence and distribution of orange-brown. Only butterflies of the genotypes EEpp and to a lesser extent Eepp are satisfactory Batesian mimics of their Euploea models. The details of the mimetic pattern are under multifactorial control, following those of their local model, as is much of the variation within the non-mimetic forms, particularly with regard to the distribution of white and blue scaling.