(No outline received).

Whilst the main aim is to study asthma, we will also investigate relations with related respiratory and atopic outcomes, namely lung function, bronchial hyper-responsiveness, atopy, rhinitis and eczema.

To collect comprehensive information about diet in around 5000 10 year-old girls.

To collect anthropometric measurements by standard methods from around 5000 girls at age 10.

To obtain comprehensive information about physical activity patterns from around 5000 girls at age 10.

To obtain information on menarcheal status and pubertal stage from around 5000 girls up to age 12.5.

To relate dietary intakes and physical activty patterns to pubertal and menarcheal status.

We propose a longitudinal, population study investigating biological and psychological processes involved in the development of gender identity, gender role behaviour and sexual orientation.

(No outline received).

(No outline received).

Cholesterol is an essential morphogenetic cofactor in developmental pathways that pattern the central nervous system during gastrulation and early embryogenesis. Adequate cholesterol is also an essential substrate for the rapid growth of neural tissues in the embryo and for synthesizing pregnancy-related steroid hormones. These critical morphogenetic events begin at embryonic day 14, prior to the establishment of a blood-brain barrier or feto-placental circulation, indicating that the embryo's early requirements may depend on uptake from the maternal circulation. Mothers with abnormally low levels of either total serum cholesterol or any essential lipoprotein fraction during the peri-conceptional period may be unable to supply the developing embryo with adequate cholesterol during this critical phase, resulting in pregnancy loss or the birth of infants with microcephaly and/or neuro-developmental disorders.

Specifically, we predict that mothers whose earliest prenatal total serum cholesterol value is within the lowest 5% of the study cohort will have an excess rate of pregnancy loss and an excess rate of microcephaly and of developmental delay in their offspring. The ALSPAC cohort is ideal for testing this hypothesis, because the number of study participants and the comprehensive pre-and post-natal data obtained from them permit an unbiased, carefully adjusted evaluation of the study hypothesis.

(No outline received).

The children in the ALSPAC cohort are now entering secondary school. The work already done in establishing the dataset means that there is now a unique opportunity to study in robust, quantitative and ground-breaking terms a number of crucial issues in the educational development of UK children. These studies will have important scientific benefits and implications for current and future Government policy. However, it is necessary to move quickly if the opportunity of putting the appropriate questions to the right individuals at the right times is not to be lost.

Other data collection will be occurring in ALSPAC through this phase, particularly in the fields of psychiatry and medicine and the investments made by related funding councils and others provide a platform for investments in educational research using ALSPAC.

A particular focus of the secondary school data collection in ALSPAC will be the motivation, engagement and attainments of pupils. Data collection will also concentrate on the impact on these aspects of development of family, school, policy and wider social factors. Planned reforms to the British education system for 14-19 year olds can be monitored by their impacts on this cohort of children. Social class differences in the process of engagement, choice and attainment of pupils can also be examined and quantified.