



@article {2314,
	title = {Sex differences in linear and complex fetal heart rate dynamics of normal and acidemic fetuses in the minutes preceding delivery},
	journal = {Journal of Perinatal MedicineJ. Perinat. Med.},
	volume = {37},
	year = {2009},
	note = {Cited By (since 1996): 4Export Date: 21 November 2012Source: ScopusCODEN: JPEMAdoi: 10.1515/JPM.2009.024PubMed ID: 19021459Language of Original Document: EnglishCorrespondence Address: Bernardes, J.; Faculdade de Medicina, Universidade Do Porto, Ginecologia e Obstetr{\'\i}cia, Al. Hernani Monteiro, Porto, 4200, Portugal; email: jbernardes59@gmail.comReferences: Ayres-de-Campos, D., Bernardes, J., Costa-Pereira, A., Pereira-Leite, L., Inconsistencies in classification by experts of cardiotocograms and subsequent clinical decision (1999) Br J Obstet Gynaecol, 106, pp. 1307-1310;Ayres-de-Campos, D., Bernardes, J., Garrido, A., Marques-de-S{\`a}, J.P., Pereira-Leite, L., SisPorto 2.0 - a program for automated analysis of cardiotocograms (2000) J Matern Fetal Med, 9, pp. 311-318; 
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},
	month = {2009///},
	pages = {168 - 176},
	abstract = {Aim: To assess linear and complex heart rate dynamics in relation to fetal gender in normal and acidemic fetuses during the minutes preceding delivery. Methods: Linear and non-linear fetal heart rate indices, namely mean FHR, long-term irregularity index, short-term variability, low and high frequency spectral indices, approximate and sample entropy, were assessed in 36 female and 30 male fetuses, adjusted for gestational age and weight, during the minutes preceding delivery. Analysis was performed in the initial and final minutes of each tracing in fetuses with umbilical artery blood pH at delivery >=7.20, 7.11-7.19 and <=7.10. Results: Progression of labor was associated with a significant decrease in non-linear indices and an increase in almost all linear indices, both in female and male fetuses, but changes were more marked in female fetuses. Non-acidemic females showed higher mean FHR in the final minutes of labor, compared with males. Acidemic females had higher linear indices when compared to similar male fetuses. Conclusions: During the minutes preceding delivery, female fetuses express higher linear indices than male fetuses, suggesting greater activation of the autonomic nervous system, while maintaining similar complexity indices, which suggests different reaction and adaptation capabilities to stress and distress. {\textcopyright} 2009 by Walter de Gruyter.},
	keywords = {acidemia, Acidemic fetuses, article, autonomic nervous system, Birth Weight, blood pH, Cross-Sectional Studies, delivery, Delivery, Obstetric, entropy, Entropy and spectral analysis, Female, Fetal Heart, fetus, fetus heart rate, Gestational Age, Heart Rate, Fetal, human, Humans, Hydrogen-Ion Concentration, Intrapartum, labor, Labor, Obstetric, male, Pregnancy, priority journal, Retrospective Studies, Sex Characteristics, sex difference, Umbilical Arteries, umbilical artery},
	isbn = {03005577 (ISSN)},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-59449089216\&partnerID=40\&md5=7a093bd5c056231b3f8150912abca652},
	author = {Bernardes, J. and Gon{\c c}alves, H. and Ayres-de-Campos, D. and Rocha, A.P.}
}
