Osteomalacia in Chronic Liver Disease

maternal renal disease, essential hypertension, diabetes, and collagen vascular disease are all causes of fetal growth retardation,' and Dawes attributed 3500 of growth-retarded pregnancies to maternal vascular disease.13 There is increasing agreement that abnormal maternal vasculature is the most important common denominator in 'intrauterine growth retardation. There is less agreement, however, about the role of vascular disease in growth-retarded pregnancies which occur in the absence of maternal hypertension. Sheppard and Bonnar12 reported uteroplacental vascular lesions in idiopathic growth retardation similar to those found in pre-eclampsia, but this association was not confirmed by Brosens and his colleagues.'4 Improvements in ultrasound hold out the promise of noninvasive methods of measuring uterine blood flow during pregnancy, and these could greatly add to our understanding of how vascular factors influence birth weight. Scott et al'5 have attempted to measure the relative contributions of different maternal factors to small-for-gestational-age pregnancies and found smoking to be the second most important after hypertension. In their population of Oxford mothers they calculated that if smoking was stopped completely, the number of affected pregnancies would fall by 3900. Those mothers who give up smoking during pregnancy in order to improve their babies' health must receive every encouragement. Cigarette smoke may not be the only noxious factor to influence birth weight; probably both alcohol and drug abuse are also causes of growth-retarded pregnancies.' Progress has been slow in the obstetric management of these pregnancies. The diagnosis is diffiCult,'6 and few therapeutic options are open to the obstetrician. We do not know whether a growth-retarded baby is better remaining in utero for as long as possible or being delivered prematurely for better nourishment in the neonatal unit. An ideal method of treatment would be one which improved intrauterine growth, allowing the pregnancy to continue to term without detriment to the fetus. Progress towards this objective will not be achieved unless methods are developed which will allow the obstetrician to diagnose intrauterine growth retardation at an early stage. Once the underlying pathological processes are well established therapeutic interventions are doomed to failure.