Breastfeeding is associated with improved child cognitive development: a population-based cohort study.

OBJECTIVE: To assess the association between breastfeeding and child cognitive development in term and preterm children. STUDY DESIGN: We analyzed data on white singleton children from the United Kingdom Millennium Cohort Study. Children were grouped according to breastfeeding duration. Results were stratified by gestational age at birth: 37 to 42 weeks (term, n = 11,101), and 28 to 36 weeks (preterm, n = 778). British Ability Scales tests were administered at age 5 years (naming vocabulary, pattern construction, and picture similarities subscales). RESULTS: The mean scores for all subscales increased with breastfeeding duration. After adjusting for confounders, there was a significant difference in mean score between children who were breastfed and children who were never breastfed: in term children, a two-point increase in score for picture similarities (when breastfed ≥ 4 months) and naming vocabulary (when breastfed ≥ 6 months); in preterm children, a 4-point increase for naming vocabulary (when breastfed ≥ 4 months) and picture similarities (when breastfed ≥ 2 months) and a 6-point increase for pattern construction (when breastfed ≥ 2 months). These differences suggest that breastfed children will be 1 to 6 months ahead of children who were never breastfed. CONCLUSIONS: In white, singleton children in the United Kingdom, breastfeeding is associated with improved cognitive development, particularly in children born preterm.

Institutional processes and individual responses: women's experiences of care in relation to cesarean birth.

BACKGROUND: Cesarean section is an increasingly common mode of birth, and although clinical care has improved and the risks reduced, less attention has been paid to the effect of the procedure and the care received. The aim of this study was to gain a better understanding by investigating individual women's recent experiences and reflections on their care. METHODS: Views of women who had recently undergone cesarean birth were obtained in a study in which a random sample of women was selected by means of birth registrations in England and invited to complete a questionnaire 3 months after the birth. Text responses to open-ended questions about care during labor and birth, the postnatal period in hospital, and anything else women wished to say about their maternity care were analyzed using qualitative methods. RESULTS: A response rate of 63 percent was achieved; 23 percent of women (n = 682) had a cesarean section birth, 53 percent of which were because of unforeseen problems in labor. A total of 66 percent of women who had a cesarean section responded to one or more open questions. Anticipated themes that were confirmed related to expectations, uncertainty, emotional reactions, pain and discomfort, explanations, support, and adjustment. Emerging themes included "being heard,""how it might have been different,""wasted effort,""just another mother,""wounds and hurt feelings," and "needing to talk." CONCLUSIONS: Women responded as individuals and despite different clinical circumstances, the role of the staff and the institutions in which care was provided were key factors in the way most women constructed their cesarean section experience. The themes described present a powerful argument and reminder about why health professionals working in maternity care need to continue to listen to women.

Antenatal and intrapartum prediction of shoulder dystocia.

OBJECTIVES: To (1) develop algorithms to calculate the risk of shoulder dystocia at individual deliveries; (2) evaluate screening for shoulder dystocia. STUDY DESIGN: Retrospective analysis of 40284 consecutive term cephalic singleton pregnancies using a 'train and test' method. Four models were derived using logistic regression and tested (birthweight alone; birthweight and other independent antenatal variables; birthweight and all independent antenatal and intrapartum variables; and all independent variables excluding birthweight). RESULTS: Shoulder dystocia occurred in 240 deliveries (0.6%). Birthweight was the most important risk factor although 98 cases (41%) occurred in babies weighing <4.0kg. Birthweight and maternal height were the only independent antenatal variables; for intrapartum use, only these and instrumental delivery were independent. The antenatal model could calculate an individual's risk; the intrapartum model could also calculate the risk if an instrumental delivery were undertaken. Both showed 0.7% women to have a risk of shoulder dystocia of >10%. Although the antenatal model had high predictability (area under curve 0.89), it was no better than birthweight alone and had a sensitivity of 52.4%. Where birthweight was excluded, prediction of shoulder dystocia was poor. CONCLUSION: Antepartum and labour calculation of the risk of shoulder dystocia is possible. Whilst greatly hindered by the inaccuracy of estimating weight, it allows due weight to be given to factors which may already be influencing clinical practice. However, shoulder dystocia cannot be predicted with sufficient accuracy to allow universal screening.

Offer and uptake of prenatal screening for Down syndrome in women from different social and ethnic backgrounds.

OBJECTIVE: To compare offer and uptake of prenatal screening for Down syndrome in women from different social and ethnic backgrounds. METHOD: A total of 4800 randomly selected women in England were sent a survey three months after they had given birth; 2960 women responded. Odds ratios (OR) for reported offer and uptake of screening comparing women by area deprivation and ethnicity were calculated. RESULTS: In all, 65% of women reported having screening; 89% reported being offered screening, and 69% of these reported taking up the offer. There was no evidence of a difference in the reported offer (adjusted OR = 0.88, 95% confidence interval (CI) 0.65-1.19, p = 0.41) or uptake (adjusted OR = 0.84, 95% CI 0.66-1.06, p = 0.15) of screening for women living in the most deprived areas compared with other women. Asian women were less likely to report being offered screening than White women (adjusted OR = 0.61, 95% CI 0.39-0.94, p = 0.02) and were less likely to take up screening when offered (adjusted OR = 0.48, 95% CI 0.33-0.72, p < 0.001). CONCLUSIONS: While most pregnant women in England are offered prenatal screening for Down syndrome, approximately 1 in 10 is not. Asian women are less likely than White women to report being offered Down syndrome screening and are less likely to have a screening test when offered.

Linking Millennium Cohort data to birth registration and hospital episode records.

The Millennium Cohort Study of 18,818 UK babies born in 2000-02 interviewed parents when the baby was 9 months old. Time constraints on the interview limited the amount of health-related questions that could be included. The aim of this study was to augment interview data with information from birth registrations and hospital records. It also provided an opportunity to assess the accuracy of the data acquired and parents' recall of the information on pregnancy and delivery. Deterministic and probabilistic matching were used to obtain information from birth registration and hospital records. Investigation into the accuracy of the matches obtained was undertaken. The records received were checked for range, consistency and completion. Birth registration data were obtained for 99% of those who gave consent. The number of additional variables gained ranged from six in Northern Ireland to 16 in Scotland. Hospital record data were obtained for 83% of those who gave consent. The additional general and maternity-related variables gained ranged from 55 in Scotland to 76 in England. Completion of available health record variables ranged from 28% to 100% across all UK countries. Linkage to birth registration and hospital records in order to augment Millennium Cohort Study data with routinely collected data was successful. The variables gained by linkage have added considerable value to the cohort study and validated some of the mother's responses.

Self-reported health status and health-related quality of life of teenagers who were born before 29 weeks' gestational age.

OBJECTIVE: The objective of this study was to describe the self-reported health status and health-related quality of life of British teenagers who are in mainstream schooling and were born before 29 weeks' gestational age compared with British teenagers who were born at term. METHODS: All surviving children who were born at <29 weeks' gestation in the former Northern Region of England in 1983 and in the former Oxford Region of England and in Scotland in 1984 were eligible. A comparison group of teenagers who were born at term were also recruited. Children's responses to the Health Utilities Index Mark III were compared. RESULTS: A total of 218 of the original 535 children who were born in the 3 regions during the study period were alive at 15 to 16 years of age. A complete Health Utilities Index Mark III record was available for 140 children in mainstream schools and for 108 control subjects. In 7 of the 8 attributes (vision, hearing, speech, emotion, pain, ambulation, and dexterity), there were no statistically significant differences in any functional impairment between the comparator groups. However, the preterm group did report a higher level of functional impairment in the cognition attribute (40.7% vs 25.0%). Although there was no difference in the median Health Utilities Index Mark III utility score between the 2 groups (0.93), there was a broader range of utility scores for the preterm group (0.07-1.0 vs 0.45-1.0 for the control group). CONCLUSIONS: Despite objective evidence that children and teenagers who were born preterm have poorer health on average than term-born control subjects, this is not reflected in their own ratings of their health status and health-related quality of life at 15 to 16 years of age. The reasons for these differences need to be further explored.

Pushing the boundaries of viability: the economic impact of extreme preterm birth.

BACKGROUND: Previous assessments of the economic impact of preterm birth focussed on short term health service costs across the broad spectrum of prematurity. OBJECTIVE: To estimate the societal costs of extreme preterm birth during the sixth year after birth. METHODS: Unit costs were applied to estimates of health, social and broader resource use made by 241 children born at 20 through 25 completed weeks of gestation in the United Kingdom and Republic of Ireland and a comparison group of 160 children born at full term. Societal costs per child during the sixth year after birth were estimated and subjected to a rigorous sensitivity analysis. The effects of gestational age at birth on annual societal costs were analysed, first in a simple linear regression and then in a multiple linear regression. RESULTS: Mean societal costs over the 12 month period were 9541 pounds sterling (standard deviation 11,678 pounds sterling) for the extreme preterm group and 3883 pounds sterling (1098 pounds sterling) for the term group, generating a mean cost difference of 5658 pounds sterling (bootstrap 95% confidence interval: 4203 pounds sterling, 7256 pounds sterling) that was statistically significant (P<0.001). After adjustment for clinical and sociodemographic covariates, sex-specific extreme preterm birth was a strong predictor of high societal costs. CONCLUSION: The results of this study should facilitate the effective planning of services and may be used to inform the development of future economic evaluations of interventions aimed at preventing extreme preterm birth or alleviating its effects.

Social class inequalities in childhood mortality and morbidity in an English population.

The objective of this study was to examine the association between social class of the head of household at the time of birth and mortality and morbidity during the first 10 years of life in a cohort of all 117 212 children born to women who both lived, and delivered in hospital, in Oxfordshire or West Berkshire during the period 1 January 1979 to 31 December 1988. Logistic regression was used to estimate social class gradients, with odds ratios (OR), for mortality during the early neonatal period, late neonatal period, post-neonatal period, post-infancy period and throughout the first 10 years of life. Logistic regression was also used to estimate social class gradients, with ORs, for hospital admission rates for 16 broad groups of diseases during years 0-3, 4-6, 7-10 and throughout the first 10 years of life. Poisson regression was used to estimate social class gradients, with effect sizes, for overall hospital admission rates during years 0-3, 4-6, 7-10 and throughout the first 10 years of life. The study revealed a significant social class gradient in mortality during the first 10 years of life (adjusted OR for each decrement in social class category 1.08; [95% confidence interval 1.03, 1.14]). The study also revealed a significant adjusted social class gradient in hospital admission rates for 14 of the 16 groups of diseases during the first 10 years of life. For the majority of these, the social class gradients had attenuated somewhat by the later childhood years. However, the social class gradient persisted throughout the first 10 years of life for diseases of the respiratory system (1.07 [1.05, 1.08]), diseases of the digestive system (1.06 [1.04, 1.09]), and injury and poisoning (1.07 [1.06, 1.09]). In addition, a significant adjusted social class gradient was found in overall hospital admission rates for each age group studied. This study suggests that there are significant social class inequalities in a wide range of adverse child health outcomes.

An investigation into the empirical validity of the EQ-5D and SF-6D based on hypothetical preferences in a general population.

BACKGROUND: An important consideration for studies that derive utility scores using multi-attribute utility measures is the psychometric integrity of the measurement instrument. Of particular importance is the requirement to establish the empirical validity of multi-attribute utility measures; that is, whether they generate utility scores that, in practice, reflect people's preferences. We compared the empirical validity of EQ-5D versus SF-6D utility scores based on hypothetical preferences in a large, representative sample of the English population. METHODS: Adult participants in the 1996 Health Survey for England (n=16 443) formed the basis of the investigation. The subjects were asked to complete the EQ-5D and SF-36 measures. Their responses were converted into utility scores using the York A1 tariff set and the SF-6D utility algorithm, respectively. One-way analysis of variance was used to test the hypothetically constructed preference rule that each set of utility scores differs significantly by self-reported health status (categorised as very good, good, fair, bad or very bad). The degree to which EQ-5D and SF-6D utility scores reflect alternative configurations of self-reported health status; illness, disability or infirmity, and medication use was tested using the relative efficiency statistic and receiver operating characteristic (ROC) curves. RESULTS: The mean utility score for the EQ-5D was 0.845 (95% CI: 0.842, 0.849), whilst the mean utility score for the SF-6D was 0.799 (95% CI: 0.797, 0.802), representing a mean difference in utility score of 0.046 (95% CI: 0.044, 0.049; p<0.001). Bland-Altman plots displayed considerable lack of agreement between the two measures, particularly at the lower end of the utility scale. Both measures demonstrated statistically significant differences between subjects who described their health status as very good, good, fair, bad or very bad (p<0.001), as well as monotonically decreasing utility scores (test for linear trend: p<0.001). The SF-6D was between 30.9 and 100.4% more efficient than the EQ-5D at detecting differences in self-reported health status, and between 10.4 and 45.6% more efficient at detecting differences in illness, disability or infirmity and medication use. The area under the curve scores generated by the ROC curves were significantly higher for the SF-6D at the 0.1% significance level when self-reported health status was dichotomised as very good versus good, fair, bad or very bad. However, the AUC scores did not reveal any significant differences in the discriminatory powers of the measures when alternative configurations of illness, disability or infirmity and medication use were examined. CONCLUSIONS: This study provides evidence that the SF-6D is an empirically valid and efficient alternative multi-attribute utility measure to the EQ-5D, and is capable of discriminating between external indicators of health status. However, health economists should also consider other psychometric properties, such as practicality and reliability, when selecting either measure for evaluative purposes.

The association between smoking during pregnancy and hospital inpatient costs in childhood.

Although the health sequelae of smoking during pregnancy are well documented, relatively little is known about its long-term economic implications. The objective of this study was to analyse individual-level data on maternal smoking behaviour and sociodemographic, perinatal and resource utilisation variables in order to estimate the association between smoking during pregnancy and hospital inpatient service utilisation and costs through the first 5 years of the infant's life. Data from the Oxford Record Linkage Study, a collection of birth registrations, death certificates and statistical abstracts of hospital inpatient and day case admissions formed the basis of the investigation. The study population comprised all infants born to women who both lived and delivered in Oxfordshire or West Berkshire during the period 1 January 1980-31 December 1989 (n = 119,028). The cost of each hospital admission, including the initial birth admission, was estimated by multiplying the length of stay by the per diem cost of the respective specialty (pound 1998-1999 sterling). The effect of maternal smoking behaviour on cumulative 5-year hospital inpatient service utilisation and costs was analysed in a series of multivariate analyses, taking account of confounding clinical and sociodemographic factors. Infants born to women who reported smoking during pregnancy were hospitalised for a significantly greater number of days than infants born to women who had either never smoked or had smoked in the past (P < 0.0001). Over the first 5 years of life, the adjusted mean cost difference was estimated at pound sterling 462 (95%CI: pound sterling 353-pound sterling 571) when infants born to women who smoked at least 20 cigarettes per day were compared to infants of non-smoking mothers, and pound sterling 307 (95%CI: pound sterling 221-pound sterling 394) when infants born to women who smoked 10-19 cigarettes per day were compared to infants of non-smoking mothers (P < 0.0001). The results of this study should add an economic dimension to the importance of providing smoking cessation services for pregnant women.

Behavioral and emotional adjustment of teenagers in mainstream school who were born before 29 weeks' gestation.

OBJECTIVES: To investigate behavioral and emotional problems and positive adjustment of 15-to 16-year-olds who were born at extremely low gestational age (ELGA), from the perspective of parents, teachers, and teenagers. METHODS: Prospective follow-up was conducted of birth cohorts, with classroom control subjects. All infants who were born before 29 weeks in 1983-1984 (mean gestational age: 27 weeks) to mothers who resided in 3 regions of the United Kingdom were studied. A total of 82% (179 of 218) of survivors were traced at age 15 to 16. The 150 in mainstream school were compared with age- and gender-matched classroom control subjects (n = 108). Behavioral and emotional problems, delinquency, peer relations, self-esteem, and hobbies, were assessed by standardized, well-validated instruments, including the Strengths and Difficulties Questionnaire, administered by mail to parents, teenagers, and teachers. RESULTS: Parents were more likely to rate ELGA teenagers than control subjects as in the "abnormal" range for hyperactivity (8% vs 1%; difference: 7%; (95% confidence interval [CI]: 2-12), peer relationship problems (19% vs 5%; difference: 14%; 95% CI: 6-21), and emotional problems (18% vs 7%; difference: 11%; 95% CI: 3-19), but not conduct problems (10% vs 5%; difference: 5%; 95% CI: -1 to 12)). Teachers reported a similar pattern. In contrast, compared with control subjects, ELGA teenagers did not rate themselves as having more problems with peers, hyperactivity, conduct, depression, or low self-esteem. They reported more emotional problems but less delinquency, alcohol, cannabis, and other drug use. CONCLUSIONS: Compared with mainstream classmates, children who are born extremely early continue to have higher levels of parent- and teacher-reported emotional, attentional, and peer problems well into their teens. However, despite these problems, they do not show signs of more serious conduct disorders, delinquency, drug use, or depression.

The impact of preterm birth on hospital inpatient admissions and costs during the first 5 years of life.

OBJECTIVES: To compare the cumulative use and cost of hospital inpatient services to 5 years of age by individuals divided into 4 subgroups by gestational age at birth. DESIGN: Costs applied to the hospital service utilization profile of each infant born in 2 areas covered by the Oxford Record Linkage Study during 1970-1993. SETTING: Oxfordshire and West Berkshire, southern United Kingdom. SUBJECTS: 239 694 individuals divided into 4 subgroups by gestational age at birth: <28 weeks, 28 to 31 weeks, 32 to 36 weeks, >or=37 weeks. MAIN OUTCOME MEASURES: Number and duration of hospital admissions during the first 5 years of life and costs, expressed in pound sterling and valued at 1998-1999 prices, of hospital inpatient services. RESULTS: The total duration of hospital admissions for infants born at <28 and at 28 to 31 gestational weeks was 85 and 16 times that for term infants, respectively, once duration of life had been taken into account. Hospital inpatient service costs were significantly higher for preterm infants than for term infants, with the cost differences persisting throughout infancy and early and mid-childhood. Over the first 5 years of life, the adjusted mean cost difference was estimated at pound 14,614 ( 22,798 US dollars) when infants born at <28 weeks gestational age were compared with term infants and pound 11,958 ( 18,654 US dollars) when infants born at 28 to 31 weeks gestational age were compared with term infants. Independent contributions to total cost came from being born: small for gestational age, a multiple, during the 1970s and early 1980s, to a woman of extreme maternal age or who was hospitalized antenatally, and from experiencing extended survival or childhood disease. However, preterm birth remained the strongest predictor of high cost. CONCLUSIONS: Preterm birth is a major predictor of how much an individual will cost hospital service providers during the first 5 years of life.