Establishment Of Ma’anshan Birth Cohort And Its Birth Outcomes

Objectives To establish Ma’anshan birth cohort and build efficient system for gatheringinformation about prenatal environmental exposures and adverse pregnancy outcomes.This birth cohort study laid the foundation for determining the relationship betweenenvironmental factors and pregnancy outcomes, child development.Methods The study was nested within a prospective population-based China-AnhuiBirth Cohort Study (C-ABCS). A total of5084women participated in this study inMa’anshan. Pregnant women attending antenatal visits at four maternal and child healthcenter (MCH) of Ma’anshan and providing with informed consent from Oct.2008toOct.2010were recruited into the cohort. MCH centres provide prenatal care andestablish the “Maternal health handbook” service which established a feedback systembetween the client and the authorities via the care provider. Information was collectedby a self-completion questionnaire combined with the “Maternal health handbook”regarding socio-demographic factors, prior adverse pregnancy history, presentpregnancy diseases, and pregnancy outcomes. The doctors recruited women andmanaged all the questionnaires in the MCH centre after uniformed training. Eachnewborn baby will be required to do a “4-2-1” physical examination at MCH centre.When the doctor detects birth defects, the population-based birth defects surveillancetable must be filled in completely. The doctors recruited women and managed all thequestionnaires in the MCH centre after uniformed training.Results This study showed that5084pregnant women have mean age of26.8years,mean height of161.2cm, mean weight of52.5kg. Their husbands have mean age of29.5 years. Among these women,23.2%women BMI less than18.5,77.1%had an urbanregistered residence and16.3%lived in rural areas. The proportions of college andabove in pregnant women and their husbands were20.6%and27.3%. As to Per capitaincome level, the proportion of≥2000yuan was41.9%.202of women were lost to follow up in their third trimester. Finally, we obtain4882women,66of whom were multiple pregnancies. Totally4948birth outcomes wereobtained in this cohort study, the incidence of live births, spontaneous abortion, fetaldeath, stillbirth, therapeutic abortion were97.0%,1.9%,0.6%,0.1%,0.3%. Among4797live births, there were4669singleton pregnancies, the prevalence of prematurebirth, low birth weight, small for gestational age, prolonged pregnancy, macrosomiawere3.5%,1.7%,3.0%,1.5%,11.1%respectively.After ruling out92spontaneous abortion women, we observed295children with birthdefects in all4856birth outcomes. Birth defect occurs in about3.09‰of twinpregnancies, compared to57.66‰in singletons.150were boys and108were girls, theincidnces were30.89‰and22.24‰.284had sigle defect and11had two or three, andthe incidences were58.48‰and2.27‰.Ma’anshan birth cohort reported a total of23nervous system congenital malformations,25eye, ear, face and neck congenital malformations,50circulatory system congenitalmalformations,7cleft lip and cleft palate,5digestive system congenital malformations,12genital organs congenital malformations,6urinary system congenital malformations,80musculoskeletal system congenital malformations,94other congenitalmalformations and5chromosomal abnormalities cases. Their incidences were4.74‰,5.15‰,10.30‰,1.44‰,1.03‰,2.47‰,1.24‰,16.47‰,19.36‰,1.03‰respectively.According to order of birth defect composition ratio, from hight to low were othercongenital malformations31%, musculoskeletal system congenital malformations26%,circulatory system congenital malformations16%, eye, ear, face and neck congenitalmalformations8%, nervous system congenital malformations7%, genital organs congenital malformations4%, cleft lip and cleft palate2%, urinary system congenitalmalformations2%, digestive system congenital malformations2%, chromosomalabnormalities2%.Conclusion This study is the first prospective longitudinal study in China aiming toexamine the effects of environmental exposures during pregnancy and the early lifeperiod on birth defects and children’s development. By establishing and maintaining theMa’anshan birth cohort, we collected information on environmental exposures duringpregnancy and child’s birth outcomes. This study also provides a new research methodwhich can accurately demonstrates the result of birth defects in Ma’anshan from2008to2010. Data of birth defects were observed dynamically. The establishment ofMa’anshan birth cohort provide technical platform to research influences ofenvironmental factors on aristogenesis and provide data to determine the relation ofenvironmental exposure before and during pregnancy and birth defects or adversepregnancy outcomes. Meanwhile, it also lays a theoretical basis to help the governmentsto make the policy to introduce birth defect prevention measures.