Impact of maternal and paternal smoking on birth outcomes.

Background: The adverse effects of maternal and paternal smoking on child health have been studied. However, few studies demonstrate the interaction effects of maternal/paternal smoking, and birth outcomes other than birth weight have not been evaluated. The present study examined individual effects of maternal/paternal smoking and their interactions on birth outcomes. Methods: A follow-up hospital-based study from pregnancy to delivery was conducted from 1997 to 2010 with parents and newborn infants who delivered at a large hospital in Hamamatsu, Japan. The relationships between smoking and growth were evaluated with logistic regression. Results: The individual effects of maternal smoking are related to low birth weight (LBW), short birth length and small head circumference. The individual effects of paternal smoking are related to short birth length and small head circumference. In the adjusted model, both parents' smoking showed clear associations with LBW (odds ratio [OR] = 1.64, 95% confidence interval [CI] 1.18-2.27) and short birth length (-1 standard deviation [SD] OR = 1.38, 95% CI 1.07-1.79; -2 SD OR = 2.75, 95% CI 1.84-4.10). Conclusions: Maternal smoking was significantly associated with birth weight and length, but paternal smoking was not. However, if both parents smoked, the risk of shorter birth length increased.

Association between Short Maternal Height and Low Birth Weight: a Hospital-based Study in Japan.

Anthropometry measurements, such as height and weight, have recently been used to predict poorer birth outcomes. However, the relationship between maternal height and birth outcomes remains unclear. We examined the effect of shorter maternal height on low birth weight (LBW) among 17,150 pairs of Japanese mothers and newborns. Data for this analysis were collected from newborns who were delivered at a large hospital in Japan. Maternal height was the exposure variable, and LBW and admission to the neonatal intensive care unit were the outcome variables. Logistic regression models were used to estimate the associations. The shortest maternal height quartile (131.0-151.9 cm) was related to LBW (OR 1.91 [95% CI 1.64, 2.22]). The groups with the second (152.0-157.9 cm) and the third shortest maternal height quartiles (158.0-160.9 cm) were also related to LBW. A P trend with one quartile change also showed a significant relationship. The relationship between maternal height and NICU admission disappeared when the statistical model was adjusted for LBW. A newborn's small size was one factor in the relationship between shorter maternal height and NICU admission. In developed countries, shorter mothers provide a useful prenatal target to anticipate and plan for LBW newborns and NICU admission.

Residential proximity to major roads and obstetrical complications.

Exposure to air pollution is linked with an increased risk of preterm births. To provide further evidence on this relationship, we evaluated the association between proximity to major roads--as an index for air pollution exposure--and various obstetrical complications. Data were extracted from a database maintained by the perinatal hospital in Shizuoka, Japan. We restricted the analysis to mothers with singleton pregnancies of more than 22 weeks of gestation from 1997 to 2012 (n=19,077). Using the geocoded residential information, each mother was assigned proximity to major roads. We then estimated multivariate adjusted odds ratios and their 95% confidence intervals (CIs) for the effects of proximity to major roads on various obstetrical complications (preeclampsia, gestational diabetes mellitus, placenta abruption, placenta previa, preterm premature rupture of membrane (pPROM), preterm labor, and preterm births). We found positive associations of proximity to major roads with preeclampsia and pPROM. Living within 200 m increased the odds of preeclampsia by 1.3 times (95% CI, 1.0-1.8) and pPROM by 1.6 times (95% CI, 1.1-2.2). Furthermore, living within 200 m increased the odds of preterm births by 1.4 fold (95% CI, 1.2-1.7). Exposure to traffic-related air pollution increased the risk of preeclampsia and pPROM in this study. We propose a mechanism responsible for the association between air pollution and preterm births.

Residential proximity to major roads and adverse birth outcomes: a hospital-based study.

BACKGROUND: Exposure to air pollution has been demonstrated to increase the risk of preterm birth and low birth weight (LBW). Although evidence has accumulated on characteristics associated with increased risk of air pollution-related health effects, most studies have been conducted in the adult population and evidence on reproductive outcomes is limited. We examined whether socio-economic position (SEP) and parental characteristics (parental behavior and co-morbidity) modified the relationship between air pollution and adverse birth outcomes. METHODS: Data were extracted from a perinatal hospital database based in Shizuoka, Japan. We restricted the analysis to mothers who delivered live-born single births from January 1997 to December 2010 (n = 16,615). Each birth was assigned proximity to major roads. Multivariate adjusted odds ratios (ORs) and their 95% confidence intervals (CIs) were estimated for the outcomes of preterm birth and term LBW. We stratified subjects by individual/area-level SEP and parental characteristics. We then measured interactions on the additive scale between the respective factors and exposure. RESULTS: Lower SEP at both individual and area levels was associated with the increased occurrence of adverse birth outcomes. Living within 200 m from a major road increased the risk of preterm birth by 1.5 times (95% CI: 1.3-1.9) and LBW by 1.2 times (95% CI: 0.9-1.6). Mothers with lower individual SEP defined by household occupation experienced higher ORs for term LBW (OR = 3.1, 95% CI: 1.2-8.2) compared with those with higher individual SEP. In contrast, mothers who lived in the highest area-level SEP region (i.e., affluent areas) showed slightly higher point estimates compared with those who lived in middle or poor areas. In addition, maternal diabetic and hypertensive status modified the association between proximity and preterm birth, while maternal smoking status modified the association between proximity and term LBW. CONCLUSIONS: The present study demonstrated that air pollution is an independent risk factor for adverse birth outcomes. Mothers with lower individual SEP and mothers living in higher SEP region may be susceptible to the adverse effect of air pollution. Maternal diabetic, hypertensive, and smoking status may also increase susceptibility to this air pollution-related health effect.

Who is at risk of inadequate weight gain during pregnancy? Analysis by occupational status among 15,020 deliveries in a regional hospital in Japan.

A lower bodyweight may be associated with adverse birth outcomes, such as low birth weight and being small for a given gestational age. In Japan, the rate of low birth weight has been increasing over the last two decades, such that both low pre-pregnancy weight and inadequate weight gain during pregnancy are viewed as critical issues in terms of the reproductive health of Japanese women. The aim of our study was to evaluate the relationship between socioeconomic status (SES) and inadequate weight gain during pregnancy. A cross-sectional, hospital-based study using data from a large hospital in Hamamatsu city, Japan, from 1997 to 2010 was conducted. Among a total of 21,855 deliveries, 15,020 participants were analyzed. Odds ratios and confidence intervals were estimated using a logistic regression model. We defined maternal occupational status as follows: home-maker married to a salaried-spouse, home-maker married to a self-employed spouse, home-maker married to a professional, all other home-makers, office worker, professional, and all other occupations. In the high SES groups (home-makers married to self-employed spouse and professional spouse, as well as office workers and professional workers), we found an association with inadequate weight gain during pregnancy, especially among underweight women. There was no association between SES and inadequate weight gain among normal-weight and overweight women. Japanese women from higher socioeconomic backgrounds appear to be at greater risk for inadequate weight gain. This result may contribute to enhancing prenatal education on pregnancy-related weight gain in Japan.

Trends of preterm birth and low birth weight in Japan: a one hospital-based study.

BACKGROUND: The proportions of preterm birth (PTB, ie., delivered before 37 gestational weeks) and low birth weight (LBW, ie., birth weight less than 2500 g at delivery) have been rising in developed countries. We sought to examine the factors contributing to the rise in Japan, with particular focus on the effects of obstetric interventions. METHODS: We used a database maintained by one large regional hospital in Shizuoka, Japan. We restricted the analysis to mothers who delivered live singleton births from 1997 to 2010 (n = 19,221). We assessed the temporal trends in PTB and LBW, then divided the study period into four intervals and compared the proportions of PTB and LBW. We also compared the newborns' outcomes between the intervals. RESULTS: PTB, in particular medically indicated PTB, increased considerably. The increase was largely explained by changes in caesarean sections. The neonatal outcomes did not worsen, and instead the Apgar scores and proportions requiring neonatal intensive care unit (NICU) admission improved. In particular, the risks of NICU admission in the interval from 2007 to 2010 were decreased among all births [odds ratio (OR): 0.84; 95% confidence interval (CI): 0.75, 0.95] and medically indicated births (OR: 0.44; 95% CI: 0.29, 0.68) compared with the interval from 1997 to 2000. CONCLUSIONS: Despite the increases in PTB as well as LBW, the present study suggests benefits of obstetric interventions. Rather than simple categorization of PTB or LBW, indicators such as perinatal mortality or other outcomes may be more appropriate for evaluation of perinatal health in developed countries.

Residential proximity to major roads and placenta/birth weight ratio.

Exposure to air pollution has been demonstrated to increase the risk of preterm birth and low birth weight. We examined whether proximity to major roads (as a marker of exposure to air pollution) is associated with increased placenta/birth weight ratio (as a biomarker of the placental transport function). Data on parental characteristics and birth outcomes were extracted from the database maintained by a major hospital in Shizuoka Prefecture, Japan. We restricted the analysis to mothers who delivered liveborn single births from 1997 to 2008 (n = 14,189). Using geocoded residential information, each birth was classified according to proximity to major roads. We examined the association between proximity to major roads and the placenta/birth weight ratio, using multiple linear regression. Proximity to major roads was associated with higher placenta/birth weight ratio. After adjusting for potential confounders, living within 200 m of a major road increased the ratio by 0.48% (95% CI = 0.15 to 0. 80). In addition, proximity to major roads was associated with lower placenta weight and birth weight. These observed associations were stronger among participants living closer to major roads. Exposure to traffic-related air pollution is associated with higher placenta/birth weight ratio. Impaired placental oxygen and nutrient transport function might be a mechanism for explaining the observed association between air pollution and low birth weight as well as preterm birth.

Residential proximity to heavy traffic and birth weight in Shizuoka, Japan.

An association between exposure to traffic-related air pollution and reduced birth weight has been suggested. However, previous studies have failed to adjust for maternal size, which is an indicator of individual genetic growth potential. Therefore, we evaluated the association of air pollution with birth weight, term low birth weight (term-LBW), and small for gestational age (SGA), with adjustment for maternal size. Individual data were extracted from a database that is maintained by a maternal and perinatal care center in Shizuoka, Japan. We identified liveborn singleton births (n=14,204). Using geocoded residential information, each birth was assigned a number of traffic-based exposure indicators: distance to a major road; distance-weighted traffic density; and estimated concentration of nitrogen dioxide by land use regression. The multivariate adjusted odds ratios and their 95% confidence intervals (CIs) for the associations between exposure indicators and outcomes were then estimated using logistic regression models. Overall, exposure indicators of air pollution showed no clear pattern of association. Although there are many limitations, we did not find clear associations between birth-weight-related outcomes and the three markers of traffic-related air pollution.

Residential proximity to major roads and preterm births.

BACKGROUND: Preterm births cause a large public-health burden, and air pollution is considered to be a potential risk factor. We evaluated the association between proximity to major roads (as an index for air pollution) and preterm births, classified by gestational age and specific clinical manifestations. METHODS: Data on parental information and birth outcomes were extracted from the database maintained by the perinatal hospital in Shizuoka, Japan. We restricted the analysis to mothers who delivered liveborn single births from 1997 to 2008 (n = 14,226). Using the geocoded residential information, each birth was classified on its proximity to major roads. We estimated the multivariate-adjusted odds ratios and their 95% confidence intervals (CIs) for the association of proximity to major roads with preterm births, using logistic regression. RESULTS: We found positive associations between proximity to major roads and preterm births at all gestational ages. Living within 200 m increased the risk of births before 37 weeks by 1.5 times (95% CI = 1.2-1.8), birth before 32 weeks by 1.6 times (1.1-2.4), and births before 28 weeks by 1.8 times (1.0-3.2). Proximity specifically increased the risk of preterm births with preterm premature rupture of the membranes and with pregnancy hypertension. CONCLUSIONS: This study demonstrates that exposure to traffic-related air pollution increases even the risk of preterm births of less than 30 weeks' gestational age and proposes a possible mechanism.

Perinatal outcome of monochorionic twins with selective intrauterine growth restriction and different types of umbilical artery Doppler under expectant management.

OBJECTIVES: To evaluate the prognosis of monochorionic twins with selective intrauterine growth restriction (sIUGR), classified according to the type of umbilical artery Doppler, under expectant management. METHODS: The outcome of 81 cases with isolated sIUGR was evaluated according to a classification based on umbilical artery (UA) Doppler diastolic flow in the IUGR twin (I: present, II: constantly absent/reverse, III: intermittently absent/reverse). Selective feticide was not considered due to legal constraints. Perinatal outcomes included perinatal death and neurological outcome at 6 months of age. RESULTS: From 81 cases with the diagnosis of sIUGR, twin-twin transfusion was diagnosed in 18 cases. This left 63 cases, of which 23 were classified as type I (36.5%), 27 as type II (42.9%) and 13 as type III (20.6%). Intrauterine death occurred in 4.3% (1), 29.6% (8) and 15.4% (2) among IUGR twins, and 4.3% (1), 22.2% (6) and 0.0% (0) among larger twins. Neonatal death occurred in 0.0% (0), 18.5% (5) and 0.0% (0) among IUGR twins, and 0.0% (0), 11.1% (3) and 23.0% (3) among larger twins. Neurological abnormalities at 6 months were found in 4.3% (1), 14.8% (4) and 23.1% (3) in smaller twins and 0.0% (0), 11.1% (3) and 38.5% (5) in larger twins, respectively. Intact survival at 6 months was recorded in 91% (21), 37% (10) and 61% (8) in smaller twins and 95% (22), 55% (15) and 38% (5) in larger twins, respectively. CONCLUSION: The outcome in monochorionic twins with sIUGR and abnormal umbilical artery Doppler is poor under expectant management. Normal Doppler seems to be associated with a good prognosis.

Transitory increase in middle cerebral artery peak systolic velocity of recipient twins after fetoscopic laser photocoagulation for twin-twin transfusion syndrome.

OBJECTIVE: It was the aim of this study to elucidate the clinical features of recipient twins with increased middle cerebral artery peak systolic velocity (MCA-PSV) after fetoscopic laser photocoagulation (FLP) for twin-twin transfusion syndrome. METHODS: Serial Doppler velocimetry of the MCA was performed in 30 recipient twins before and after FLP. Clinical data and perinatal outcome were compared between cases with and without increased MCA-PSV. RESULTS: Increased MCA-PSV was observed in 7 recipients (23.3%) within 14 days after FLP. MCA-PSV gradually decreased to <1.5 multiples of median in 6 recipients; however, 1 patient resulted in fetal demise subsequent to the demise of the co-twin. The incidences of fetal and neonatal demise and neurological morbidity were similar. No recipient was diagnosed as anemic at birth. CONCLUSIONS: The increase in MCA-PSV in recipients following FLP appeared to be generally transitory; this differs from twin anemia-polycythemia sequence.

Anticholinergics induce eclamptic seizures.

Severe preeclampsia is a pathophysiological disorder specific to pregnancy and characterized by vasoconstriction and hypercoagulability. Eclampsia (convulsion associated with preeclampsia) and hemolysis, elevated liver enzymes, and low platelet count associated with preeclampsia (HELLP syndrome) are serious complications in patients with severe preeclampsia. They are thought to be characterized by generalized vasoconstriction and reduction in blood flow to various organs that may be explained by increased sensitivity of the vascular smooth muscles and increased vasopressors. Liver involvement in eclampsia and preeclampsia is referred to as HELLP syndrome, and epigastric and right upper quadrant pain is often a symptom of severe preeclampsia and may be indicative of imminent convulsions. In addition, marked dilatation of the stomach and the colon is often demonstrated in these patients. These phenomena result from the hyperactivity of the sympathetic nervous system but are not caused by the hyperactivity of the parasympathetic nervous system. The authors experienced two cases of eclamptic seizures after the administration of an anticholinergic (scopolamine butylbromide) in patients with severe preeclampsia complicated by HELLP syndrome. Anticholinergics, blocking agents of the parasympathetic nervous system, can enhance the hyperactivity of the sympathetic nervous system; therefore, vasospasms of the vessels may be easily aggravated, and eclamptic seizures may be induced in patients with severe preeclampsia, especially in those complicated by HELLP syndrome. The administration of anticholinergics should be avoided in patients with severe preeclampsia, especially when there is epigastralgia.