Biomedical subjects

I Rogers

Publications and source records attributed to I Rogers.

At least 19 recordsLinked to original sources

PubMed2005

Early life risk factors for obesity in childhood: cohort study.

OBJECTIVE: To identify risk factors in early life (up to 3 years of age) for obesity in children in the United Kingdom. DESIGN: Prospective cohort study. SETTING: Avon longitudinal study of parents and children, United Kingdom. PARTICIPANTS: 8234 children in cohort aged 7 years and a subsample of 909 children (children in focus) with data on additional early growth related risk factors for obesity. MAIN OUTCOME MEASURES: Obesity at age 7 years, defined as a body mass index (3) 95th centile relative to reference data for the UK population in 1990. RESULTS: Eight of 25 putative risk factors were associated with a risk of obesity in the final models: parental obesity (both parents: adjusted odds ratio, 10.44, 95% confidence interval 5.11 to 21.32), very early (by 43 months) body mass index or adiposity rebound (15.00, 5.32 to 42.30), more than eight hours spent watching television per week at age 3 years (1.55, 1.13 to 2.12), catch-up growth (2.60, 1.09 to 6.16), standard deviation score for weight at age 8 months (3.13, 1.43 to 6.85) and 18 months (2.65, 1.25 to 5.59); weight gain in first year (1.06, 1.02 to 1.10 per 100 g increase); birth weight, per 100 g (1.05, 1.03 to 1.07); and short (< 10.5 hours) sleep duration at age 3 years (1.45, 1.10 to 1.89). CONCLUSION: Eight factors in early life are associated with an increased risk of obesity in childhood.

Body Mass Index↗

PubMed2005

Trends in waist circumferences in young British children: a comparative study.

OBJECTIVE: To compare waist circumference (a measure of central fatness) and body mass index (BMI, a measure of general fatness) between a contemporary cohort and similar aged British children measured in 1987. DESIGN: : Comparative study of two cohorts. The first was a cross-sectional survey and the second an ongoing longitudinal survey. SETTING: : The cross-sectional study was conducted throughout Great Britain during 1987. The ongoing longitudinal study was conducted in the Avon region between 1995 and 1998. PARTICIPANTS: A total of 1821 children were measured in the cross-sectional study, and around 1000 children were measured in the longitudinal study. Ages ranged between 2 and 5 y. MAIN OUTCOME MEASURES: Waist circumference, height, weight and BMI. Values were expressed as mean+/-s.d. Age-related measures were compared. RESULTS: At equivalent ages, mean waist circumference values were greater in the contemporary children, compared with children measured in the earlier cross-sectional study in 1987 (P<0.05). Although boys from the contemporary cohort had the larger absolute waist circumference measurements, the absolute and percentage differences in waist circumference between the cohorts were greater for the girls. Mean BMI values were slightly but significantly higher in the contemporary children compared with children measured in the earlier cross-sectional study (P<0.05). The proportional increase in waist circumference for each age-sex group generally exceeded the proportional increase in BMI. CONCLUSION: These results suggest that central fatness in young British children has increased over the period of 1987-97 to a greater extent than general fatness. This should be of concern since evidence associates greater central adiposity with adverse levels of cardiovascular risk factors in children. Furthermore, the study highlights important shortcomings of the BMI measurement, in that it provides no information on body fat distribution and can mask true obesity-related risk in children.

Adipose Tissue↗

PubMed2005

Food and nutrient intakes of a population sample of 7-year-old children in the south-west of England in 1999/2000 - what difference does gender make?

OBJECTIVES: To describe the diet of schoolchildren aged 7 years, and identify gender differences in food and nutrient intakes. SUBJECTS: A cohort of children resident in the south-west of England in 1999/2000. METHODS: Diet was assessed using three 1-day unweighed food diaries. Nutrient intakes were compared with dietary reference values for this age group, and with children aged 7-10 years in the British National Diet and Nutrition Survey. Food and nutrient intakes were contrasted between boys and girls. RESULTS: Median nutrient intakes exceeded the reference nutrient intake (RNI) for most nutrients. Median intakes of iron and zinc were below the RNI. Median sodium intake was greater than the maximum set by the Scientific Advisory Committee on Nutrition. The mean energy intake for boys and girls, respectively, were 7.3 and 6.8 MJ, this is below the estimated average requirement. The percentage of energy from fat was 35.3% for boys and 36.1% for girls. Boys had higher iron intakes than girls, even after adjustment for energy intake. There were differences in the types of foods eaten between boys and girls; girls ate more fruit and vegetables (P = 0.001) and boys ate more breakfast cereals (P = 0.016). CONCLUSIONS: The dietary intakes of these 7-year-old children were adequate for most nutrients. However, a reduction in the sodium content of the diet would be advantageous. Fruit and vegetable consumption should be encouraged particularly among boys.

Child↗

PubMed2004

Maternal fish intake in late pregnancy and the frequency of low birth weight and intrauterine growth retardation in a cohort of British infants.

OBJECTIVE: To investigate the relation between maternal fish intake in late pregnancy and the frequency of low birth weight and intrauterine growth retardation (IUGR). PARTICIPANTS: 11 585 pregnant women in south west England. METHODS: Information on fish intake was obtained from a food frequency questionnaire sent to the women at 32 weeks' gestation, and used to calculate n-3 fatty acid (n-3FA) intake from fish. IUGR was defined as a birth weight for gestational age and sex below the 10th centile. Confounding variables considered included maternal age, height, weight, education, parity, smoking and drinking in pregnancy, and whether the mother was living with a partner. Only singleton, liveborn infants were included. MAIN RESULTS: Mean daily intakes of fish and n-3FAs were 32.8 g and 0.147 g respectively. In unadjusted analyses there were positive associations between mean birth weight and fish intake or n-3FA intake, but these disappeared on adjustment for potential confounders. The frequency of IUGR decreased with increasing fish intake-the OR (95%CI) of IUGR in those eating no fish was 1.85 (1.44 to 2.38) compared with those in the highest fish intake group. On adjustment this relation was attenuated (adjusted OR 1.37 (1.02 to 1.84)), but the decline in the frequency of IUGR with increasing fish intake remained statistically significant. No relation was observed between mean gestation and fish or n-3FA intake. CONCLUSIONS: These results lend some support to the hypothesis that raising fish or n3-FA intake during pregnancy may increase fetal growth rate. However, they provide no evidence that increasing fish consumption is associated with an increase in mean gestation.

Analysis of Variance↗

PubMed2003

Fluoride release from orthodontic cements-effect of specimen surface area and depth.

OBJECTIVE: The aims of this in vitro study were firstly to compare fluoride release from a disc model of two orthodontic cements with various surfaces varnished, reducing the surface area by 25, 50 and 75%; secondly, to measure the fluoride release from previously exhausted discs of the same cements following removal of various depths of surface material. METHODS: Forty discs of each cement, Fuji Ortho LC and Ultra Band-Lok, (6mm diameter by 3mm) were divided into two groups of 20 discs each. For each material, the first group was divided further into four groups of five discs, one group acting as control, while the other three groups were varnished reducing the surface area by 25, 50 and 75%, respectively. The second group was exhausted initially over a 60 day pre-experimental period and was subsequently divided into four groups of five discs, one group acting as control. The other three groups had material ground from one of the flat surfaces, to depths of 10, 100 or 1000 microm, to reveal a fresh surface. In both studies, the discs were immersed either daily (up to day 20) or twice weekly (up to day 60) in fresh 2ml aliquots of deionised water. The fluoride concentration in the deionised water was measured at the end of the experimental period. RESULTS: For each cement, the relationship between the cumulative fluoride release and the percentage of the surface covered was clearly non linear at both 5 and 60 days. Fuji Ortho LC proved to release significantly greater amounts of fluoride at both 5 days and 60 days compared with Ultra Band-Lok. The results for Ultra Band-Lok were also significant when compared to the control group, but significantly less fluoride was released when compared with Fuji Ortho LC. When comparing the 25 and 50% covered discs, the amount of fluoride released was not significantly different for both cements. Furthermore, the relationship between fluoride release and depth was clearly non linear for both cements. CONCLUSIONS: For the materials tested in this study, reducing the surface area of the discs did not reduce the cumulative fluoride release in a linear fashion. In addition, the previously exhausted discs began to release fluoride again, but this fell to concentrations similar to the control discs after the initial 5-day period for both cements. This suggests that further traces of previously unreleased fluoride had become available from the subsurface of these cements. The pattern of fluoride release was similar for all models tested.

Acrylic Resins↗

PubMed2003

The effect of maternal smoking status, educational level and age on food and nutrient intakes in preschool children: results from the Avon Longitudinal Study of Parents and Children.

OBJECTIVE: Studies in adults have demonstrated that smoking status is associated with dietary quality, with smokers tending to have diets that conform less closely to guidelines on healthy eating than nonsmokers. However, there is very little information on the relation between children's dietary quality and parental smoking status. The objective of this study was to investigate the relation between maternal smoking status and nutrient intake in preschool children, allowing for the possible confounding effects of maternal educational level and age at delivery. SUBJECTS: In total, 993 children aged 18 months participating in the Avon Longitudinal Study of Parents and Children. METHODS: Diet was assessed by a 3-day food record. Maternal smoking status and educational level and age at delivery were assessed by questionnaire. RESULTS: In multivariate analysis, the children of smokers had significantly higher intakes of monounsaturated fatty acids and starch, and lower intakes of nonstarch polysaccharides (NSP). They were also less likely to have eaten poultry, buns, cakes and puddings, wholemeal bread and fruit, and more likely to have drunk sugar-sweetened soft drinks. Intakes of NSP and most vitamins and minerals increased significantly with increasing maternal education. Children of more highly educated mothers were less likely to have eaten chocolate, crisps and white bread, and more likely to have consumed wholemeal bread, fruit and fruit juice. CONCLUSIONS: The children of nonsmokers and more highly educated mothers consumed a diet that conformed more closely to current guidelines on healthy eating. These dietary differences may contribute to the excess of ill-health observed in the children of smokers and of less-educated mothers.

Age Factors↗

PubMed2003

The influence of birthweight and intrauterine environment on adiposity and fat distribution in later life.

OBJECTIVE: To review the literature on the association between birthweight and body mass index (BMI) and obesity in later life. METHODS: Included in the review were papers appearing in Medline since 1966 and identified using the search terms obesity, body fat, waist, body constitution, birthweight and birth weight. Further papers were identified by examining bibliographies. RESULTS: There is good evidence that there is an association between birthweight and subsequent BMI and overweight in young adults and children, which is linear and positive in some studies and J- or U-shaped in others. The evidence is less strong for middle-aged subjects. Studies that have assessed lean body mass (LBM) and fat body mass have tended to find that birthweight is positively associated with LBM and negatively associated with relative adiposity. This suggests that the association between birthweight and BMI/overweight does not necessarily reflect increased adiposity at higher birthweights. On controlling for current body mass there is fairly consistent evidence of a negative association between birthweight and a central pattern of fat distribution as measured by central:peripheral skinfold ratios. It has been suggested that the prenatal period is a 'critical' period for the development of adiposity, but it is unclear how far associations between birthweight and subsequent body habitus are genetic in origin and how far they result from intrauterine 'programming'. Two lines of evidence would suggest that the association is predominantly genetic. Studies of monozygotic twins have found environmentally determined differences in birthweight to be unrelated to subsequent BMI, and the association between birthweight and BMI is substantially reduced on controlling for parental BMI. However, some evidence of an influence of intrauterine environment on later obesity comes from studies of subjects who were exposed in utero to the effects of diabetes, famine conditions or smoking. CONCLUSIONS: The reasons for the positive association between birthweight and BMI remain unclear. More studies including accurate measurement of body composition are needed to assess how far this relation is accounted for by changes in fat mass or by changes in lean mass. Studies with accurate measures of parental BMI would also be useful in assessing the importance of this confounder.

Adipose Tissue↗

PubMed2002

Drinks consumed by 18-month-old children: are current recommendations being followed?

OBJECTIVE: To examine the types of drinks consumed by children at 18 months of age, determine any associations with socio-demographic characteristics and investigate the use of a bottle for providing these drinks. DESIGN: A total of 1026 randomly chosen children from the Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC) were studied. METHODS: As part of a dietary diary completed when their children were 18 months of age, mothers were asked to record all drinks consumed over a 24 h period and to report the containers used to give these drinks. Socio-demographic characteristics were obtained via self-completion questionnaire. RESULTS: Dietary records were available for 1026 children at 18 months. A wide variety of drinks were given at this age. In all, 64% of children had received at least one drink in a bottle and 10% solely used a bottle. Bottle users consumed a significantly greater volume of milk drinks compared to those who used a cup or other container. The types of drinks consumed and adherence to the guidelines on weaning were associated with several socio-demographic characteristics. In particular, children with mothers of lower educational level were more likely to receive fizzy drinks and low-calorie soft drinks, more likely to drink from a bottle, and less likely to drink from a cup. CONCLUSION: We have shown that certain groups of mothers with 18-month-old children are not following the current guidelines on weaning. Assuming these guidelines have scientific validity, it is clear that nutritional education needs to be targeted at these mothers to help them feed their children in the optimal way, to protect from nutritional deficiencies, possible later obesity and poor dental health. SPONSORSHIP: University of Bristol.

Analysis of Variance↗

PubMed2002

Fat content of the diet among pre-school children in Britain; relationship with food and nutrient intakes.

OBJECTIVE: To investigate the relationship between the percentage of energy from fat and food and nutrient intakes at 18 and 43 months of age. DESIGN: Diet was assessed using a 3 day unweighed food record. The children were divided into quartiles of fat intake as a percentage of energy (QFI), and food and nutrient intakes in the different QFIs were compared. SUBJECTS: A total of 1026 children at 18 months and 863 children at 43 months, taking part in the Avon Longitudinal Study of Pregnancy and Childhood, participated. RESULTS: At 18 months the mean (s.d.) fat intake was 31.2 (2.8) % of energy in the lowest QFI and 43.1 (2.2) % in the highest. Energy intake increased slightly with increasing QFI. The percentage of energy derived from total sugar, and in particular non-milk extrinsic sugar fell as QFI increased, as did the ratio of polyunsaturated to saturated fatty acids. Intakes of retinol equivalents and zinc increased significantly with increasing QFI, while intakes of iron and most water soluble vitamins fell. There was a particularly marked fall in vitamin C intake as fat intake increased, from 11.8 mg/MJ in the lowest QFI, to 6.0 mg/MJ in the highest (P<0.001). Consumption of whole milk increased substantially with percentage energy from fat, from 51 g/MJ in the lowest QFI to 116 g/MJ in the highest (P<0.001), while consumption of fruit and fruit juice fell. The results obtained at 43 months were very similar. CONCLUSIONS: The chances of a suboptimal intake of zinc and retinol were higher at lower fat intakes. However, intakes of the fat-soluble vitamins E and D were unrelated to fat intake and intakes of iron and vitamin C fell as fat intakes increased. Some suggestions for improving diet in this age group have been given. SPONSOR: University of Bristol.

Child Nutritional Physiological Phenomena↗

PubMed2001

Randomized controlled trial of midazolam premedication to reduce the subjective adverse effects of adenosine.

OBJECTIVE: To determine the safety and efficacy of midazolam premedication to minimize the subjective adverse effects of adenosine. METHODS: Double-blind prospective randomized controlled trial of patients presenting to an urban emergency department. Included were a convenience sample of patients who would have received adenosine by the existing department protocol. Exclusion criteria were pregnancy, benzodiazepine allergy, regular benzodiazepine medication, alcoholism, altered mental state (precluding informed consent), and age less than 18 or greater than 65 years. Subjects received either 1.5 mg of intravenous midazolam or normal saline placebo 5 min prior to the administration of adenosine. Side-effect recall was judged by a questionnaire at 1 h and 24 h postadenosine administration. RESULTS: A total of 34 patients were recruited into the trial, 16 in the placebo group and 18 in the midazolam group. The groups were well matched for demographics, treatment and outcome. There was a significant reduction in the midazolam group for complaint scores of palpitations (P = 0.04) and chest pain (P = 0.02) and a trend to reduction in complaint scores for most other parameters. There were no adverse outcomes in any of the patients studied. CONCLUSIONS: Co-administration of midazolam can safely reduce the recall of the unpleasant adverse effects of adenosine. Its use may be most appropriate in patients who are particularly anxious or have had previous adverse experiences with adenosine.

Adenosine↗

PubMed2001

Human UC-blood banking: impact of blood volume, cell separation and cryopreservation on leukocyte and CD34(+) cell recovery.

BACKGROUND: UC blood represents an increasingly useful source of hematopoietic stem cells for BMT, although, currently, low cell numbers generally limit its use to pediatric patients. We have determined parameters that influence the recovery of viable cells during processing and cryopreservation, in an effort to set guidelines for determining whether a sample will yield sufficient cells to be of use in the transplant setting. METHODS: UC blood was collected from donors from January 1996 to December 1999. Volume was reduced using Ficoll, followed by cryopreservation under liquid nitrogen. Total leukocyte and CD34(+)-cell counts were determined prior to processing and a subset of samples was also assessed post-processing and post-cryopreservation. RESULTS: Outcomes for 3816 samples were analyzed to determine the correlation between cell number, cell type, volume, and time between collection and processing. A positive relationship was observed between volume and cell number for both leukocytes and the CD34(+) cells. This correlation allowed us to determine the number of leukocytes and CD34(+) cells expected from a sample based on volume, and to set guidelines for determining the practicality of storing any given sample prior to processing and cryopreservation. DISCUSSION: Measuring blood volume gives a very useful indication of the total leukocyte and CD34(+) cell number. The majority (75%) of cord-blood samples contain sufficient leukocytes for a pediatric transplant, and the number of cells available can be determined prior to processing by measuring blood volume.

Antigens, CD34↗

PubMed2001

Controlling culture dynamics for the expansion of hematopoietic stem cells.

The ex vivo expansion of hematopoietic stem cells (HSCs) is the subject of intense commercial and academic interest due to the potential of HSCs to be a renewable source of material for cellular therapeutics. Unfortunately, because methodologies have not yet been developed to grow clinically relevant numbers of HSCs (or their derivatives) consistently, the potential of this technology is limited. Manipulation of the in vitro culture microenvironment, primarily through cytokine supplementation, has been the predominant approach in studies attempting to expand primary human HSC numbers in vitro. While promising results have been obtained, it is becoming clear that novel methods must be developed before cellular therapies using these stem cells can become routine. Ideally, bioprocesses must be designed to target specifically the growth of stem cell populations while incorporating positive and negative feedback from potentially dynamic mature and maturing cell populations. The product of these culture systems should consist of not only HSCs, but also of cells that allow the engraftment of HSCs and, ideally, cells responsible for the immediate or accelerated functional support of patients. Development of such "designer transplants" will require combining optimal culture conditions capable of amplifying HSC numbers with novel approaches for finely controlling the number, functional capabilities, and characteristics of potentially therapeutic cells in these very complex cell culture systems.

Animals↗

PubMed2000

LiCl disrupts axial development in mouse but does not act through the beta-catenin/Lef-1 pathway.

Chimera and cell marking studies suggest that axial determination in mouse embryos occurs at postimplantation stages. In contrast, Xenopus laevis axes are determined early due to the asymmetric distribution of maternally derived factors in the one-cell zygote. In our earlier study we used lithium chloride (LiCl) to perturb development of mouse axes. Here we investigate whether the lithium induced axial defects in mouse are being mediated by the beta-catenin/Lef-1 pathway as in Xenopus laevis. In lithium treated embryos we did not observe any changes in the amount or localization of beta-catenin protein. Furthermore, the lack of Lef-1 mRNA in treated and untreated embryos indicates the LiCl induced axial defects in the mouse are not mediated by the beta-catenin/Lef-1 pathway.

Animals↗

PubMed2000

Hyponatremia and seizures in an ultradistance triathlete.

Hyponatremia is being increasingly recognized as a complication of participation in ultra-endurance sports. Reported is the case of an Ironman triathlete who collapsed at the end of the race, having gained 5% in body weight. His serum sodium concentration at the finish was 116 mmol/L. After an Intensive Care Unit course complicated by recurrent seizures, he eventually made a complete neurologic recovery. The pathogenesis of hyponatremia and its management in such cases is discussed.

Adult↗

PubMed1999

Elderly trauma patients admitted to the intensive care unit are different from the younger population.

AIMS: This study was undertaken to investigate the demographic profile of elderly (65 years old and over) patients with severe trauma admitted to the Intensive Care Unit of Auckland Hospital and to compare their characteristics with those of the younger (under 65 years) trauma patients. A further aim was to see if specific areas of potential injury prevention could be identified. METHOD: Data analysis covering ten years, from January 1987 to December 1996, on data extracted from the existing database at the Intensive Care Unit of Auckland Hospital. RESULTS: The elderly comprised 8.7% (183 of 2092) of the trauma admissions during the study period. The elderly, when compared with the younger group, were significantly more likely to be female, New Zealand European and admitted as a result of a fall. They were significantly less likely to be drivers in a road traffic crash or, if a driver, to have a blood alcohol above the legal limit. Mortality in the older group (27.8%) was significantly higher, though median injury severity score (25) and length of stay (57.9 hours) were similar. CONCLUSIONS: Elderly trauma patients in the Intensive Care Unit are a group with distinctive demographics, mechanisms of injury, injury types and outcomes. This information needs to be considered for the future planning of trauma and prevention services in New Zealand.

Age Factors↗

PubMed1998

Expression of SC1 is associated with the migration of myotomes along the dermomyotome during somitogenesis in early mouse embryos.

SC1 is a secreted glycoprotein with a high amino acid sequence similarity to SPARC (Secreted Protein, Acidic, Rich in Cysteine). SC1 transcripts were first detected in mouse embryos after day 8.5 post coitus (p.c.) in somites at the medial lip of the dermomyotome. Expression of SC1 transcripts by the progenitor cells continued as they began involuting under the dermomyotome and during their migration along the lateral wall of the dermomyotome. After myotome migration was completed, SC1 mRNA expression was downregulated in the trunk region. The data indicate that SC1 expression is restricted to the initial stages of epaxial myotome differentiation and migration, undergoing rapid downregulation prior to myotome emigration from the somitic environment.

Activated-Leukocyte Cell Adhesion Molecule↗

PubMed1998

Diet during pregnancy in a population of pregnant women in South West England. ALSPAC Study Team. Avon Longitudinal Study of Pregnancy and Childhood.

OBJECTIVE: To describe the diet of a population of pregnant women. SUBJECTS: Eleven thousand, nine hundred and twenty-three pregnant women resident in the south-west of England. DESIGN: A self-completion unquantified food-frequency questionnaire was sent to the women at 32 weeks gestation. Estimated daily nutrient intakes were calculated from the answers to the questionnaire. RESULTS: On the whole, nutrient intakes of the pregnant women in this survey compared very closely with the reported nutrient intakes for all women aged 16-64 in the last Dietary and Nutritional Survey of British Adults (DNSBA). The exceptions were sugar, calcium, folate and vitamin C where the estimated intakes were somewhat higher, and retinol, where the estimated intake was somewhat lower than the DNSBA. Mean and median estimated nutrient intakes were above the RNIs for the majority of nutrients investigated except for energy, iron, magnesium, potassium and folate. Levels of supplementary vitamin and mineral use were fairly low, the two most commonly taken supplements were iron--taken by 22.5% of the pregnant women before 18 weeks and 43% at 32 weeks, and folate, taken by 9% and 18% of the women, respectively. CONCLUSIONS: These results suggest that the diets of pregnant women in this country are likely to contain adequate amounts of most nutrients, the most likely exceptions being iron, magnesium, potassium and folate. The relatively low intakes of folate and small proportion of women taking folate supplements is of concern, because of the association between inadequate amounts of folate in the diet and neural tube defects.

Adolescent↗

PubMed1998

Financial difficulties, smoking habits, composition of the diet and birthweight in a population of pregnant women in the South West of England. ALSPAC Study Team. Avon Longitudinal Study of Pregnancy and Childhood.

OBJECTIVE: To investigate the relationships between self-assessed financial difficulties, diet in pregnancy and birthweight. DESIGN: Information on diet composition, difficulty in affording food, smoking habits and parity was collected by self-completion questionnaires at 32 weeks of pregnancy. Information on birthweights was obtained from hospital records. SUBJECTS: A geographically defined population 11833 pregnant women resident in the South-West of England. MAIN OUTCOME MEASURES: Nutrient intakes, food choices and birthweight. RESULTS: Women with greater difficulty in affording food had lower intakes of protein, fibre, vitamin C, niacin, pyridoxine, iron, zinc, magnesium and potassium than did women with little or no difficulty. They were more likely to use cooking and spreading fats with a high saturates content, and less likely to eat fish, fruit, vegetables and salad. In a multivariate analysis including parity and smoking status, financial difficulty was found to have no significant relationship with birthweight. CONCLUSION: The quality of diet in pregnancy falls with increasing difficulty in affording food. However, this does not appear to affect mean birthweight of infants born after 32 weeks gestation.

Adolescent↗