Pregnancy planning, smoking behaviour during pregnancy, and neonatal outcome

Abstract Objective. To investigate the independent effects of pregnancy planning and smoking during pregnancy on neonatal outcome. Design. Population-based cohort study. Setting. UK Millennium Cohort Study. Sample. 18,178 singleton babies born in UK between 2000 and 2001. Methods. Logistic regression was used to estimate the association between pregnancy planning and/or smoking and neonatal outcome. Adjusted odds ratios were used to calculate population attributable risk fractions(PAFs). Main Outcome measures. Low birthweight (<2.5Kg) and pre-term birth (<37 completed weeks gestation). Results. 43% of mothers did not plan their pregnancy and 34% were smoking just before and/or during pregnancy. Planners were half as likely to be smokers just before pregnancy, and more likely to give up or reduce the amount smoked if smokers. Unplanned pregnancies had 24% increased odds of low birth weight and prematurity compared to planned pregnancies (AOR LBW 1.24, 95%CI1.04-1.48; AOR PREM 1.24, 95%CI1.05-1.45), independent of smoking status. The odds of low birth weight for babies of mothers who were smoking just before pregnancy was 91% higher than that of mothers who were not (AOR LBW 1.91, 95%CI1.56-2.34). Women who quit or reduced the amount smoked during pregnancy lowered the risk of low birth weight by one third (AOR LBW 0.66, 95% CI0.51-0.85) compared with women whose smoking level did not change. Smaller effects were found for prematurity. If all women planned their pregnancy and did not smoke before or during pregnancy, 30% of low birthweight and 14% of prematurity could, in theory, be avoided. Conclusions. Planning a pregnancy and avoiding smoking during pregnancy has clear, independent, health benefits for babies. Quitting or reducing the amount smoked during pregnancy can reduce the risk of low birthweight

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Pregnancy planning, smoking behaviour during pregnancy, and neonatal outcome: UK Millennium Cohort Study.

BACKGROUND: Pre-pregnancy health and care are important for the health of the future generations. Smoking during pregnancy has been well-researched and there is clear evidence of harm. But there has been little research on the health impact of planning for pregnancy. This study aims to investigate the independent effects of pregnancy planning and smoking during pregnancy on neonatal outcome. METHODS: This analysis made use of data from the UK Millennium Cohort Study. The study sample consisted of 18,178 singleton babies born in UK between 2000 and 2001. The neonatal outcomes of interest were low birthweight (<2.5 Kg) and pre-term birth (<37 completed weeks gestation). Logistic regression was used to estimate the association between pregnancy planning and/or smoking and neonatal outcome. Adjusted odds ratios were used to calculate population attributable risk fractions (PAFs). RESULTS: 43% of mothers did not plan their pregnancy and 34% were smoking just before and/or during pregnancy. Planners were half as likely to be smokers just before pregnancy, and more likely to give up or reduce the amount smoked if smokers. Unplanned pregnancies had 24% increased odds of low birth weight and prematurity compared to planned pregnancies (AORLBW1.24, 95% CI 1.04-1.48; AORPREM1.24, 95% CI 1.05-1.45), independent of smoking status. The odds of low birth weight for babies of mothers who were smoking just before pregnancy was 91% higher than that of mothers who were not (AORLBW1.91, 95% CI 1.56-2.34). Women who quit or reduced the amount smoked during pregnancy lowered the risk of a low birth weight baby by one third (AORLBW0.66, 95% CI 0.51-0.85) compared with women whose smoking level did not change. Smaller effects were found for prematurity. If all women planned their pregnancy and did not smoke before or during pregnancy, 30% of low birthweight and 14% of prematurity could, in theory, be avoided. CONCLUSIONS: Planning a pregnancy and avoiding smoking during pregnancy has clear, independent, health benefits for babies. Quitting or reducing the amount smoked during pregnancy can reduce the risk of low birthweight