title: Fetal sex and preterm birth.
abstract: Rates of preterm birth vary between different populations and ethnic groups. Epidemiologic studies have suggested that the incidence of preterm birth is also higher in pregnancies carrying a male fetus; the male:female difference is greater in earlier preterm pregnancy. Placental or chorion trophoblast cells from pregnancies with a male fetus produced more pro-inflammatory TNFα in response to LPS stimulation and less anti-inflammatory IL-10 and granulocyte colony stimulating factor (G-CSF) than cells from pregnancies with a female fetus, more prostaglandin synthase (PTGS-2) and less prostaglandin dehydrogenase (PGDH). These results suggest that in the presence of a male fetus the trophoblast has the potential to generate a more pro-inflammatory environment. Maturation of the fetal hypothalamic-pituitary-adrenal axis and expression of placental genes, particularly 11β hydroxysteroid dehydrogenase-2 are also expressed in a sex dependent manner, consistent with the sex-biasing influences on gene networks. Sex differences in these activities may affect clinical outcomes of pre- and post-dates pregnancies and fetal/newborn wellbeing. These factors need consideration in studies of placental function and in the development of personalized strategies for the diagnosis of preterm labor and postnatal health.
authors.affiliation: University of Toronto, Dept Obstetrics and Gynecology, Mount Sinai Hospital, Samuel Lunenfeld Research Institute, Toronto, ON, Canada. j.challis@utoronto.ca
authors.forename: J
authors.initials: J
authors.lastname: Challis
authors.forename: J
authors.initials: J
authors.lastname: Newnham
authors.forename: F
authors.initials: F
authors.lastname: Petraglia
authors.forename: M
authors.initials: M
authors.lastname: Yeganegi
authors.forename: A
authors.initials: A
authors.lastname: Bocking
mesh_terms: D043209:11-beta-Hydroxysteroid Dehydrogenase Type 2 / Q000378:metabolism; D005260:Female; D005333:Fetus / Q000503:physiopathology*; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000503:physiopathology; D007231:Infant, Newborn; D018836:Inflammation Mediators / Q000502:physiology; D008297:Male; D007752:Obstetric Labor, Premature / Q000209:etiology / Q000503:physiopathology; D010913:Pituitary-Adrenal System / Q000503:physiopathology; D010920:Placenta / Q000503:physiopathology; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000209:etiology / Q000503:physiopathology; D047928:Premature Birth / Q000209:etiology* / Q000503:physiopathology*; D019936:Probiotics / Q000627:therapeutic use; D012307:Risk Factors; D012727:Sex Characteristics; D013312:Stress, Physiological; D014327:Trophoblasts / Q000502:physiology
chemical_list: D018836:Inflammation Mediators; D043209:11-beta-Hydroxysteroid Dehydrogenase Type 2