Hiroo Naruse

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.

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 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 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.

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

BackgroundThe 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.MethodsWe 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.ResultsPTB, 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.ConclusionsDespite 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.

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.

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.

Fetoscopic Laser Photocoagulation for the Treatment of Twin-Twin Transfusion Syndrome in Monochorionic Twin Pregnancies

Fetoscopic laser surgery for severe twin-twin transfusion syndrome (TTTS) has become the optimal treatment choice since the release of the Eurofetus randomized clinical trial. These techniques have been adopted throughout the globe, and many institutions have instituted or will soon institute fetoscopic laser surgery procedures; however, laser sur- gery has a steep learning curve because of the following: challenging placental location, complex and unexpected com- municating anastomoses, residual anastomoses after surgery, or discolored amniotic fluid. We have been performing laser surgery since 2002 in Japan; to date, we have compiled a series of 170 cases. Our data indicates a 78% of overall survival with 5% neonatal morbidity, 63% of survival of both twins, and 93% survival of at least one twin. The recurrent TTTS rate was 1% and the residual vessel rate was 3%. To improve the learning curve of laser surgery, the employment of various techniques is recommended to achieve a suc- cessful surgical outcome: (1) Mapping: before laser ablation, a very thorough mapping of vascular anastomoses should be done, and should be repeated after ablation; (2) Sequential order: obliteration of arterio-venous anastomoses from donor to recipient should be done first to avoid donor hypotension and/or anemia; (3) Trocar (cannula) assisted technique: Trocar assisted technique: Using gentle indent the trocar to the placenta by withdrawing the scope shortly, then anastomoses could be ablated easily; (4) Line method: to avoid residual anastomoses, the laser should draw a virtual line at the hemo- dynamic equator; The operator must be careful not to miss small anastomoses. These techniques can help achieve a successful outcome for fetoscopic laser surgery and improve the outcome for cases of severe TTTS.

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.

The Treatments of Twin-Twin Transfusion Syndrome in MonochorionicTwin Pregnancies by the Fetoscopic Laser Photocoagulation

Aims: Fetoscopic laser surgery has been widely accepted of optimal treatment for Twin-Twin Transfusion Syndrome (TTTS) in monochorionic twin pregnancies. To avoid surgical complication and to improve the outcome, various techniques employed in our institution. The aim of our study is to assess the clinical outcomes of TTTS after laser surgery with combined various techniques. Methods: We performed 171 cases of fetoscopic laser surgery for TTTS from 2002 to 2011 in our institution. Various techniques employed in our studies to improve the learning of laser surgery and to achieve successful outcome were; (1) A very thorough mapping of vascular anastomoses before and after ablation; (2) Obliteration of arterio-venous anastomoses from donor to recipient should be done first, (3) Trocar assisted technique using gentle indent the trocar withdrawing the scope shortly, to ablate anastomoses easily, (4) A virtual line was drawn by laser at the hemodynamic equator to avoid residual anastomoses, and not to miss small anastomoses. Results: Laser photocoagulation was performed since 2002 in our institute, compiling 171 cases. Overall survival was 78% with 5% neonatal morbidity. Both twins survived for 64%, and the survival of one twin was 93%. The recurrent TTTS rate was 1%, and the residual vessel rate was 2%. Conclusion: A successful outcome for fetoscopic laser surgery is achievable and the outcome is improved in severe TTTS cases by these techniques.