The Tanner and Whitehouse reference curves for body segment length are not suitable for contemporary British children, whose legs are longer than they were a generation ago. It is proposed that the curves presented here be adopted provisionally as the new British reference.

SUMMARY In a study designed to provide retrospective control data for a neonatal thyroid screening programme, the problems of 141 hypothyroid children were examined. The mean IQ (Weschler intelligence scale) was 79-5 for children with congenital hypothyroidism but was normal in 6 children diagnosed before age 6 weeks. Diagnostic delay was associated with a steady decline in mean IQ but there was an improvement in some late diagnosed cases. A strong association was found between IQ and parental social class. Twenty five percent of the children were mentally retarded and 29% were at special schools; 54% of children at normal schools and 43% at special schools showed deviant behaviour. Other problems included clumsiness (26-2%) and squints (26-2%), and these were more common in children with a lower IQ. Congenital hypothyroidism is associated with persistent morbidity in many aspects of cerebral function. The adverse effects of prenatal hypothyroidism are largely reversible if treated before age 6 weeks.Neonatal screening for congenital hypothyroidism (CH) has been progressively introduced throughout North America, Japan, and Europe over the past five years and is now also universal in the United Kingdom. In none of these screening programmes has it been considered ethical to conduct any controlled trial of the value of screening itself. Thus the assessment of the results depends in part on comparison with retrospective studies of children with clinically diagnosed CH. Because previous retrospective studies had shown an improvement in mean IQ with earlier diagnosis,' 2 screening was expected to be effective in preventing mental retardation and reversing the effects of intrauterine hypothyroidism. Some doubts were, however, expressed by McFaul et al.3 as to whether screening would be fully effective in preventing all the long term complications of CH. In particular they found that some children diagnosed between 4 and 10 weeks of age had evidence of clumsiness, visual disorders, learning difficulties, and behaviour problems. The present study was undertaken to see if these findings were representative of an unselected group of children with CH and also to provide up to date retrospective data for comparison with children diagnosed by screening. Patients and methodsAltogether 141 hypothyroid children were included in the study. The names of 98 children were obtained by writing to all the paediatricians in the four Thames health regions. To ensure that other handicapped hypothyroid children were not missed, the 21 area health authorities in these regions were asked to supply the names of children with CH from the handicap registers, and this produced 41 more children. Two children were found who were in long stay mental hospitals. While the handicap registers gave the names of only 4 children who were not seeing a paediatrician regularly, they helped considerably in tracing children who were attending hospital clinics.Data on the mode of presentation and confirmatory tests were obtained from the case notes.

Thirty-six neonates in whom hypothyroidism was diagnosed after thyroid stimulating hormone screening were reassessed at 1 year. All had grown satisfactorily and the mental development scores were normal in all except two. Treatment was withdrawn in 32 and persistent hypothyroidism was confirmed in 31 cases. Thyroid stimulating hormone concentrations were raised in onethird of cases before the withdrawal of treatment and this was associated with generally lower concentrations of serum thyroxine (T4) and smaller doses of L-thyroxine than in those cases with normal concentrations of thyroid stimulating hormone.In treating congenital hypothyroidism, serum T4 concentrations should be monitored regularly and the dose of thyroxine adjusted to maintain serum T4 in the upper part of the reference range.

SUMMARY Eighty children from the North West and North East Thames Regional Health Authorities who had been identified as having congenital hypothyroidism either by neonatal screening (76 cases) or by clinical symptoms (four) were seen for psychological assessments at 1 (60 cases), 3 (58), and/or 5 (20) years of age. Almost all the children's scores were in the normal range, and comparisons with matched controls suggested that they were doing only slightly less well than normal children in overall development. They were significantly slower, however, on a motor skills task. Moreover, a low initial serum thyroxine and triiodothyronine value, considerable delay in initial bone age, and an absence of thyroid tissue on isotope scan seemed to be associated with a somewhat poorer prognosis.Over the last few years many countries have set up neonatal screening programmes for the'detection of congenital hypothyroidism. It had been anticipated that early recognition and treatment of congenital hypothyroidism would ameliorate the adverse psychological sequelae of delay in starting treat-

Community paediatricians are increasingly asked to provide expert opinion on internet child pornography related to 'sex tourism', mostly in south-east Asian countries. The girls involved are often prepubertal, and the main legal question is to establish whether they are under 13 years of age. This paper provides a review of the literature related to '97.5% of south-east Asian girls will show pubertal changes of B2 stage by the age of 13.7 years' this question. Although there are limited data of age of menarche from the countries at risk of 'sex tourism', one recent study from the Philippines showed that the mean age of menarche was similar to the mean age of British girls born between 1982 and 1986. There are no data in the above countries on the early pubertal changes in breast development, but studies from India and China suggested that these might be more prolonged than for British girls. In particular, the interval between B2 stage (early pubertal breast development) and menarche was nearly 3 years in these developing countries, compared with 2 years for the British girls. Maternal malnutrition and girls small for gestational age at birth resulted in an earlier menarche, while chronic malnutrition, severe enough to cause stunting in preschool years, caused a delay in menarche. Taking into account information from the existing studies, we estimated that 97.5% of south-east Asian girls will show pubertal changes of B2 stage by the age of 13.7 years.