Maternal pre-pregnancy weight has been related with young singletons’ cognitive and behavioral development, but it is not clear if it has an effect on temperament. We used a twin cohort to evaluate the association between maternal pre-pregnancy body mass index (BMI) and infants’ temperament. The mothers of 834 twins answered questions regarding their pre-pregnancy BMI and their 0- to 18-month-old children’s temperament using the Revised Infant Behavior Questionnaire. Three temperamental dimensions were examined: activity level, distress to limitation and duration of orienting. The relationship between maternal pre-pregnancy BMI and each temperamental component was investigated by means of multilevel mixed-effects linear regression analysis. We found no clear evidence of an association of maternal pre-pregnancy BMI with twins’ temperament. The development of temperament is influenced by a large number of factors, probably different from those influencing children’s emotional and behavioral development.

Adverse intrauterine environment could serve as an important stimulus for postnatal altered health status and for increased susceptibility to long-term non-communicable diseases (NCDs). The notion is now recognized as the Developmental Origins of Health and Disease (DOHaD), which was first proposed by Sir David Barker. Since then, several scientific disciplines have strived to measure the magnitude of the early fetal programming and later risk of diseases. Pakistan, with striking figures of morbidity and mortality from NCDs, is currently tackling with double burden of diseases and requires planned efforts to counteract the threat of NCDs. Considering the growing needs and available evidences, Pakistan DOHaD Society was officially instigated in September 2016. The Society aims to explicitly address the association of life in utero with future health and disease and to endorse early screening and interventions to reduce the burden of NCDs, mental health issues and learning disorders along the life course. It has shown significant progress toward investigating the influence of adverse in utero environment such as diabetes, maternal under-nutrition and pre-eclampsia on fetal programming under two major research lines, that is, cardiovascular and cerebrovascular programming. The Society has been successful in disseminating its research findings through several esteemed international scientific conferences. Pakistan DOHaD Society encourages scientific community for collaborative research aimed at improving the quality of life during early childhood, adolescence and adulthood through provision of appropriate pre-pregnancy and antenatal interventions targeted to address at-risk in utero conditions.

Problem behaviors are of increasing public health concern. Twin studies have revealed substantial genetic and environmental influences on children's behavior, and examining birth-weight difference could allow the identification of the specific contribution of multiple non-shared prenatal environmental factors. The Twins and Multiple Births Association Heritability Study, a UK, volunteer-based study, recruited mothers of twins aged 18 months to 5 years; 960 twins (480 pairs) were included in the analysis. Twins’ mothers answered questions relative to their pregnancy and their twins’ characteristics, and completed the Child Behavior Checklist (CBCL) 1½–5. The association between the absolute birth-weight difference and each CBCL scale's score difference was analyzed by means of multiple linear regressions. Expected mean CBCL score differences were calculated. In monozygotic (MZ) twins, statistically and clinically significant associations were found between intrapair birth-weight difference and difference in total problems, internalizing problems, and emotional reactiveness. No significant results were observed neither in dizygotic (DZ) twins when analyzed as a separate group nor in MZ and DZ twins combined. The results of the present study suggest that with increasing the absolute birth-weight difference, the intrapair difference in total problems, internalizing behaviors and emotionality increases, with smaller twins being at major risk for later behavior problems. Moreover, these results suggest a causal association between birth weight and behavior development.

Intrauterine environmental factors can be associated with perinatal complications and long-term health outcomes although the underlying mechanisms remain poorly defined. Meconium formed exclusively in utero and passed naturally by a neonate may contain proteins which characterise the intrauterine environment. The aim of the study was proteomic analysis of the composition of meconium proteins and their classification by biological function. Proteomic techniques combining isoelectrofocussing fractionation and LC-MS/MS analysis were used to study the protein composition of a meconium sample obtained by pooling 50 serial meconium portions from 10 healthy full-term neonates. The proteins were classified by function based on the literature search for each protein in the PubMed database. A total of 946 proteins were identified in the meconium, including 430 proteins represented by two or more peptides. When the proteins were classified by their biological function the following were identified: immunoglobulin fragments and enzymatic, neutrophil-derived, structural and fetal intestine-specific proteins. Meconium is a rich source of proteins deposited in the fetal intestine during its development in utero. A better understanding of their specific biological functions in the intrauterine environment may help to identify these proteins which may serve as biomarkers associated with specific clinical conditions/diseases with the possible impact on the fetal development and further health consequences in infants, older children and adults.

Intrauterine factors important for cognitive development, such as birth weight, chorionicity and umbilical cord characteristics were investigated. A total of 663 twin pairs completed the Wechsler Intelligence Scale for Children-Revised and scores were available for Performance, Verbal and Total Intelligence Quotient (IQ). The intrauterine factors examined were birth weight, placental weight and morphology, cord knots, cord length and cord insertion. IQ scores for the varying levels of the intrauterine markers adjusting for gender and gestational age were calculated. The heritability of IQ and the association between IQ and intrauterine environment were examined. Twins with lower birth weight and cord knots had lower IQ scores. The aetiology of IQ is largely distinct from that of birth weight and cord knots, and non-shared environment may influence the observed relationships.