RESUMO
OBJECTIVE: To determine the rate of live birth per blastocyst based on morphology and oocyte age using data from a single center. METHODS: This is a mathematical analysis and model building study of autologous blastocyst stage embryo transfers at a University-affiliated center. A total of 448 blastocyst stage embryos were transferred in 244 fresh and frozen embryo transfers from May 2015 through April 2018. Blastocyst morphology was divided into good, fair, and poor overall morphology grades. Each embryo transfer was modeled as an equation equating the sum of the unknown live birth rates of the transferred embryos to the number of live births that resulted. The least squares solution to the system of embryo transfer equations was determined using linear algebra. RESULTS: Trophectoderm morphology was a better predictor of live birth rate than inner cell mass morphology. Embryos graded AA/AB/BA (good) had the highest live birth rates followed by BB/CB (fair), and BC/CC (poor). In our youngest age group (25-32 years) live birth rates per embryo were 51% for good, 39% for fair, and 25% for poor quality embryos. In our oldest age group (40-44 years) the live birth rates per embryo were 22% for good, 14% for fair, and 8% for poor quality embryos. CONCLUSIONS: These techniques can help analyze small datasets such as those from individual clinics to aid in determining the ideal number of embryos to transfer to achieve live birth while limiting the risk of multiple gestations.
Assuntos
Coeficiente de Natalidade , Fertilização in vitro , Adulto , Blastocisto , Transferência Embrionária , Feminino , Humanos , Nascido Vivo/epidemiologia , Gravidez , Estudos RetrospectivosRESUMO
BACKGROUND: Tobacco exposure might be a modifiable risk factor for atopic dermatitis (AD). OBJECTIVE: We examine the association between AD and exposure to tobacco smoke. METHODS: We performed a systematic review and meta-analysis of observational studies (n = 86) in MEDLINE, EMBASE, Scopus, and Cochrane Library (1823-2015). Quality of evidence was assessed using the Newcastle-Ottawa Scale (NOS). A meta-analysis was performed using random-effects models to estimate pooled odds ratios (OR). Subset analyses were performed for different ages (children, adult), regions, study designs (cross-sectional, longitudinal), study sizes (<5000, ≥5000), study quality (NOS score <6, ≥6), and amount of smoking (mild, extensive). RESULTS: A diagnosis of AD was associated with higher odds of active smoking (OR 1.87, 95% confidence interval 1.32-2.63) and exposure to passive smoke (OR 1.18, 95% confidence interval 1.01-1.38), but not maternal smoking during pregnancy (OR 1.06, 95% confidence interval 0.80-1.40). The association between active smoking and AD remained significant in children and adults, all continents studied, and study sizes, but all were cross-sectional designs and had NOS score 6 or greater. Passive smoke was associated with AD in children and adults, cross-sectional studies, South/Central American and African studies, study size less than 5000, and NOS score less than 6. LIMITATIONS: AD severity and distribution were not assessed. CONCLUSIONS: Active and passive exposure to smoke are associated with increased AD prevalence.