Research | Children’s Health Genetic, Biochemical, and Environmental Factors Associated with Pregnancy Outcomes in Newborns from the Czech Republic Pavel Rossner Jr., Nana Tabashidze, Miroslav Dostal, Zuzana Novakova, Irena Chvatalova, Milada Spatova, and Radim J. Sram Laboratory of Genetic Ecotoxicology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic Background : Oxidative damage to placental DNA can result in negative pregnancy outcomes, including intrauterine growth restriction (IUGR) and low birth weight (LBW). o Bjectiv : We investigated associations between the levels of 8-oxo-7,8-dihydro-2´-deoxyguanosine (8-oxodG), a marker of oxidative DNA damage, in placental DNA, exposure to air pollutants dur- ing pregnancy, genetic polymorphisms in 94 selected genes, and pregnancy outcomes. Methods : We studied 891 newborns who were IUGR- or LBW-affected or normal weight and were born between 1994 and 1999 in the Czech Republic in two districts with different levels of air pollution. r sulte : We found nonsignificantly elevated 8-oxodG levels in the IUGR-affected group compared with the non-IUGR group (p = 0.055). Similarly, slightly elevated 8-oxodG levels were found in the LBW-affected group compared with the non-LBW group (p < 0.050). In univariate analyses, we identified single nucleotide polymorphisms associated with 8-oxodG levels, IUGR, and LBW. Exposure to particulate matter < 2.5 µm was associated with increased 8-oxodG levels in placental DNA and LBW. However, multivariate-adjusted logistic regression revealed that above-median 8-oxodG levels were the only factor significantly associated with IUGR [OR = 1.56; 95% confi- dence interval (CI), 1.07–2.37; p = 0.022]. Above-median levels of 8-oxodG were associated with LBW (OR = 1.88; 95% CI, 1.15–3.06; p = 0.011). Other variables associated with LBW included sex and gestational age of the newborn, maternal smoking, and haplotypes in the promoter region of the gene encoding mannose-binding lectin 2 (MBL2). The role of air pollutants in the risk of adverse pregnancy outcomes seemed to be less important. c onclusi : Levels of 8-oxodG in placental DNA were associated with the risk of IUGR as well as LBW. Newborn’s sex, gestational age, maternal smoking, and genetic polymorphisms in the pro- moter region of the MBL2 gene were associated with LBW incidence. k eywords : air pollution, biomarkers, genetic polymorphisms, oxidative damage, pregnancy outcomes. Environ Health Perspect 119:265–271 (2011). doi:10.1289/ehp.1002470 [Online 5 October 2010] Negative pregnancy outcomes affect millions of newborns worldwide. It is estimated that at least 15% of children are born with low birth weight (LBW): weight < 2,500 g (Gluckman and Hanson 2006). In the Czech population, the incidence of LBW in the 1990s was about 5%, and up to 10% in polluted regions (Sram et al. 1991). According to the recent data, the incidence of LBW increased to 7.11% in 2008 (Institute of Health Information and Statistics of the Czech Republic 2008). A newborn who fails to achieve a weight thresh- old for his or her gestational age is charac- terized as small for gestational age (SGA). Intrauterine growth restriction (IUGR) is a syndrome of SGA fetuses who have failed to reach their growth potential for various reasons, including genetic factors, infections, or placental disorders. Therefore, IUGR can be described as a pathological form of SGA (Bamberg and Kalache 2004). LBW and particularly IUGR newborns often suffer from various negative health consequences. Mortality and morbidity have been shown to be increased among newborns whose birth weights are at or below the third percen- tile of their gestational age (McIntire et al. 1999). Cognitive impairment and the need for special education have also been shown to be increased, as well as a higher incidence of premature birth, among children born small (reviewed by Gluckman and Hanson 2006). Longer-term consequences of LBW include higher risks of cardiovascular diseases, obstructive pulmonary disease, type 2 diabe- tes mellitus, renal insufficiency, and impaired reproductive functions (Barker 1995; Saenger et al. 2007). Various factors have been suggested as causes of LBW syndromes. They include medical conditions of the mother, maternal social conditions, fetal problems, abnormali- ties of the placenta, and environmental factors (Bamberg and Kalache 2004; Saenger et al. 2007). Abnormal pregnancy outcomes may also be associated with specific genetic poly- morphisms, dysregulated immune responses, aberrant angiogenesis (Li and Huang 2009), and increased oxidative stress in the pla- centa and maternal circulation (Poston and Raijmakers 2004). Among a complex mixture of chemicals present in the ambient air, polycyclic aro- matic hydrocarbons (PAHs) are particularly Environmental Health Perspectives • volume 119 | number 2 | February 2011 important, because some of them are carcino- genic (c-PAHs) and may be directly respon- sible for the increased incidence of cancer due to PAH–DNA adduct formation and sub- sequent mutation induction (Lewtas 2007). PAHs, as well as other chemicals in the air, are adsorbed onto the surface of particulate matter (PM) of various aerodynamic diam- eters. Exposure to PM < 2.5 µm (PM2.5) is associated with increased all-cause lung cancer and cardiopulmonary mortality (Pope et al. 2002). A major consequence of PM expo- sure in humans is the generation of reactive oxygen species (ROS), which can occur via various mechanisms that include metabolism, redox cycling, and inflammation and result in oxidative damage to DNA and other macro- molecules (Moller et al. 2008). Oxidative stress mediated by PM has been proposed as one of the mechanisms responsible for adverse pregnancy outcomes (Kannan et al. 2006). Increased oxidative stress, accompanied by reduced translation of proteins, including key signaling molecules, is present in the placentas of IUGR preg- nancies (Yung et al. 2008). Oxidative stress causes injury to chorionic villi, reducing the functional mass of the syncytiotrophoblast and limiting the capacity of the villi to medi- ate nutrient transport, thus contributing to IUGR induction (Scifres and Nelson 2009). Inflammation, also related to oxidative stress induction, is another key process associated with LBW syndromes. Whereas normal preg- nancy is a state of permanent mild inflam- mation, in adverse pregnancy outcomes, the inflammation is increased above normal levels (Li and Huang 2009). The resulting inflam- matory state is accompanied by maternal leukocyte activation, the release of cytokines from immune cells and uteroplacental tis- sues, and endothelial cell activation, as well as Address correspondence to R.J. Sram, Institute of Experimental Medicine AS CR, Videnska 1083; 142 20 Prague 4, Czech Republic. Telephone: 420- 24106-2596. Fax: 420-24106-2785. E-mail: sram@ biomed.cas.cz Supplemental Material is available online (doi:10.1289/ehp.1002470 via http://dx.doi.org/). The study was supported by the Czech Ministry of the Environment (SP/1b3/50/07) and the Academy of Sciences of the Czech Republic (AVOZ50390512). The authors declare they have no actual or potential competing financial interests. Received 21 May 2010; accepted 5 October 2010. 265