title: Atmospheric conditions, lunar phases, and childbirth: a multivariate analysis.
abstract: Our objective was to assess extrinsic influences upon childbirth. In a cohort of 1,826 days containing 17,417 childbirths among them 13,252 spontaneous labor admissions, we studied the influence of environment upon the high incidence of labor (defined by 75th percentile or higher), analyzed by logistic regression. The predictors of high labor admission included increases in outdoor temperature (odds ratio: 1.742, P = 0.045, 95%CI: 1.011 to 3.001), and decreases in atmospheric pressure (odds ratio: 1.269, P = 0.029, 95%CI: 1.055 to 1.483). In contrast, increases in tidal range were associated with a lower probability of high admission (odds ratio: 0.762, P = 0.030, 95%CI: 0.515 to 0.999). Lunar phase was not a predictor of high labor admission (P = 0.339). Using multivariate analysis, increases in temperature and decreases in atmospheric pressure predicted high labor admission, and increases of tidal range, as a measurement of the lunar gravitational force, predicted a lower probability of high admission.
authors: School of Arts, Science and Humanities-Midwifery Department, University of Sao Paulo (USP), Sao Paulo City, Sao Paulo, Brazil. angelaochiai@usp.br
authors: Angela Megumi
authors: AM
authors: Ochiai
authors: Fabio Luiz Teixeira
authors: FL
authors: Gonçalves
authors: Tercio
authors: T
authors: Ambrizzi
authors: Lucia Cristina
authors: LC
authors: Florentino
authors: Chang Yi
authors: CY
authors: Wei
authors: Alda Valeria Neves
authors: AV
authors: Soares
authors: Natalucia Matos
authors: NM
authors: De Araujo
authors: Dulce Maria Rosa
authors: DM
authors: Gualda
mesh_terms: D000293:Adolescent; D000328:Adult; D001272:Atmosphere; D001938:Brazil; D005260:Female; D006801:Humans; D016081:Moon; D015999:Multivariate Analysis; D036801:Parturition; D011247:Pregnancy; D055871:Tidal Waves; D055815:Young Adult