Association between PM10 air pollution and birth weight after full-term pregnancy in Krakow city 1995–2009 – trimester specificity

Introduction and objective. The results of epidemiological studies indicate that the higher maternal exposure to air pollution, especially with particulate matter during pregnancy, the lower the infant’s birth weight. The aim of this study was to estimate entire pregnancy and trimester-specific exposure of pregnant women in the city of Krakow, southern Poland, to fine particulate matter [≤10 μg (PM10)], and to assess its effect on the birth weight of boys and girls separately. Material and methods. The study group consisted of 85,000 singleton, live, full-term births in Krakow city during a 15-year period (data from the birth registry). The mean concentrations of the pollutant for each month of gestation were estimated using continuous municipal monitoring data. Results. Multiple linear regression analyses indicated that the mean PM10 concentration during entire pregnancy was inversely associated with birth weight in girls and the group of boys and girls combined, after adjusting for maternal age, gestational age and year of birth; in boys the relationship was not statistically significant. Maternal exposure to PM10 during the first trimester was negatively associated with birth weight separately in girls and boys, and the group of boys and girls combined. However, the PM10 exposure during the second and third trimester of pregnancy was not associated with birth weight. Conclusions. PM10 air pollution at levels currently encountered in Krakow city adversely affect infant birth weight; however, the effect seems to be very small. The influence of particulate air pollution on foetal growth in early gestation is one of several possible explanations for the results, but further research is needed to establish possible biological mechanisms explaining the observed relationship

Low estradiol levels in women of reproductive age having low sleep variation

Higher exposure to light at night per se and through decrease in sleep duration and night shift work may suppress serum melatonin levels, which in turn may increase the reproductive hormone levels. High levels of steroid hormones, especially estrogens, may be associated with an increase of the breast cancer risk. This study investigated whether variation in the sleep duration during one entire menstrual cycle corresponds to variation in estradiol levels in healthy, urban women of reproductive age. Ninthy five regularly menstruating women ages 24-36 collected daily saliva samples for one entire menstrual cycle and recorded the number of hours of sleep per night (sleep duration). Saliva samples were analyzed for concentration of 17-ß estradiol (E2). We documented, after adjustments for sleep duration, a positive relationship between the sleep variation (coefficient of variation in sleep duration - sleep CV) and estradiol levels in women of reproductive age. Mean levels of E2 differed significantly in women from the lowest sleep CV quartile in comparison to other quartiles (p<0.001). The low sleep variation group, that is the women who sleep regularly, had mean E2 levels 60% lower than other groups. These results suggest that sleep variation significantly correlates with E2 levels, while sleep duration does not show a statistically significant relationship. According to the breast cancer development hypothesis, increasing the lifetime exposure to endogenous estrogens could result in higher risk of breast cancer.AnthropologyHuman Evolutionary Biolog

Marital Status, Father Acknowledgement, and Birth Outcomes: Does the Maternal Education Matter?

We evaluated whether the maternal marital status and father acknowledgement (proxy for paternal presence) affect birth weight, and if so, whether the maternal educational attainment modifies this effect. The growing tendency of alternative forms of family structure affects maternal well-being and pregnancy outcome. However, it is not known whether poorer birth outcomes of out-of-wedlock childbearing can be overcome or compensated by maternal education. Using birth registry data, we assessed the impact of maternal civil status and child recognition by the father on birth-weight-for-gestational age (BWGA) z-scores, with respect to maternal education, among Polish mothers (N = 53,528). After standardization, the effect of being unmarried with father acknowledgement (UM-F) vs. married with father acknowledgement (M-F) reduced the BWGA z-score of 0.05 (p &lt; 0.001), irrespective of educational attainment (p for interaction = 0.79). However, education differentiated the effect of father acknowledgement across unmarried mothers. BWGA z-scores were significantly lower among the low-educated unmarried group without father acknowledgment (UM-NF) as compared to UM-F (equaled &minus;0.11, p = 0.01). The same effect among the higher-educated group was non-significant (p = 0.72). Higher maternal education can compensate for the negative effect of a lack of father acknowledgement, but it does not help to overcome the effect of out-of-wedlock stress exposure

Association between PM10 air pollution and birth weight after full-term pregnancy in Krakow city 1995–2009 – trimester specificity

Introduction and objective The results of epidemiological studies indicate that the higher maternal exposure to air pollution, especially with particulate matter during pregnancy, the lower the infant’s birth weight. The aim of this study was to estimate entire pregnancy and trimester-specific exposure of pregnant women in the city of Krakow, southern Poland, to fine particulate matter [≤10 µg (PM10)], and to assess its effect on the birth weight of boys and girls separately. Material and Methods The study group consisted of 85,000 singleton, live, full-term births in Krakow city during a 15-year period (data from the birth registry). The mean concentrations of the pollutant for each month of gestation were estimated using continuous municipal monitoring data. Results Multiple linear regression analyses indicated that the mean PM10 concentration during entire pregnancy was inversely associated with birth weight in girls and the group of boys and girls combined, after adjusting for maternal age, gestational age and year of birth; in boys the relationship was not statistically significant. Maternal exposure to PM10 during the first trimester was negatively associated with birth weight separately in girls and boys, and the group of boys and girls combined. However, the PM10 exposure during the second and third trimester of pregnancy was not associated with birth weight. Conclusions PM10 air pollution at levels currently encountered in Krakow city adversely affect infant birth weight; however, the effect seems to be very small. The influence of particulate air pollution on foetal growth in early gestation is one of several possible explanations for the results, but further research is needed to establish possible biological mechanisms explaining the observed relationship

The Effect of Prenatal Stress, Proxied by Marital and Paternity Status, on the Risk of Preterm Birth

Uncertainty and insecurity in the relationship between the mother and father of a child are responsible for heightened maternal stress, which can lead to preterm birth (PTB). Different intensities of prenatal stress (proxied by four levels of marital status linked with the presence or absence of paternal data on birth records) were defined as the Marital-Father Data index. We assessed the impact of those varying intensities of prenatal stress on PTB with respect to parity among a group of Polish mothers residing in Krakow (N = 87,916). We found a pattern across the adjusted risk ratios (RR) of preterm birth that ordered these estimates in an increasing trend towards higher risk, beginning with the group of married mothers with father data present (baseline), through the groups of legitimizing marriages&mdash;married after conception with father data present (RR = 1.1; 95% Confidence Intervals (CI) 1.0&ndash;1.2) and unmarried mothers with father data present (RR = 1.3; 95% CI 1.2&ndash;1.5) to the group of unmarried mothers with father data absent (RR = 1.9; 95% CI 1.7&ndash;2.2). The adjusted p for the linear trend between Marital-Father Data index and PTB was less than 0.001. The adjusted effect of perceived prenatal stress differed with respect to parity (confirmed by statistically significant interactions between Marital-Father Data index levels and parity), with a higher magnitude of this effect noted among multiparous versus primiparous women. Low paternal involvement and support during pregnancy may negatively affect PTB risk and this effect may differ in relation to parity status. More attention should be paid to maternal pregnancy stress, especially of multiparous mothers, to decrease the risk of unfavorable birth outcomes

Joint effect of particulate matter and cigarette smoke on women's sex hormones

Background Although relationships between exposure to air pollution and reproductive health are broadly studied, mechanisms behind these phenomena are still unknown. The aim of the study was to assess whether exposure to particulate matter (PM10) and tobacco smoking have an impact on menstrual profiles of 17β-estradiol (E2) and progesterone (P) and the E2/P ratio. Methods Levels of sex hormones were measured daily in saliva during the entire menstrual cycle among 132 healthy, urban women. Exposure to smoking (active or passive) was assessed by questionnaire, whilst exposure to PM10 with municipal monitoring data. Results During the early luteal phase, profiles of E2 were elevated among women with higher versus lower exposure to PM10 (p = 0.02, post-hoc tests). Among those who were exposed versus unexposed to tobacco smoking, the levels of mean E2 measured during the entire cycle were higher (p = 0.02). The difference in mean E2 levels between the group of joint exposure (i.e. to high PM10 and passive or active smoking) versus the reference group (low PM10, no smoking) was statistically significant at p = 0.03 (18.4 vs. 12.4 pmol/l, respectively). The E2/P ratios were higher among women with higher versus lower exposure to PM10 and this difference was seen only in the early luteal phase (p = 0.01, exploratory post-hoc tests). Conclusions We found that PM10 and tobacco smoking affect ovarian hormones independently and do not interact with each other. Both exposures appear to have estrogenic effects even though women's susceptibility to these effects differs across the menstrual cycle. We propose that the hormonal mechanisms are involved in observed relationships between air pollution and smoking with women’s reproductive health