The influence of prenatal screening and termination of pregnancy on perinatal mortality rates.

OBJECTIVES: This study concerns the possible effect of practice of prenatal screening of congenital anomalies followed by termination of pregnancy on the perinatal mortality between European countries. METHODS: Data of nine region-specific EUROCAT registries from five European countries were used to compare the pregnancy termination rate and perinatal mortality due to congenital anomalies between the registries. The impact of pregnancy terminations on the perinatal mortality rate was estimated using a calculated lethality for each congenital anomaly in the hypothetical case that no pregnancy terminations had been performed and was expressed in the 'natural' perinatal mortality rate. RESULTS: There are large differences between the EUROCAT registries in the number of pregnancy terminations for congenital anomalies. The difference between the 'natural' and regular perinatal mortality rate vary between 3.7 and 14.1 per 10 000 live births and stillbirths. The difference is greater in regions where prenatal screening is more common than in regions where this is not common. CONCLUSION: Differences in practice of prenatal screening and termination of pregnancy of congenital anomalies contribute to the variations in the overall perinatal mortality rate between European regions and countries.

Double-blind intervention trial on modulation of ozone effects on pulmonary function by antioxidant supplements.

The aim of this study was to investigate whether the acute effects of ozone on lung function could be modulated by antioxidant vitamin supplementation in a placebo-controlled study. Lung function was measured in Dutch bicyclists (n = 38) before and after each training session on a number of occasions (n = 380) during the summer of 1996. The vitamin group (n = 20) received 100 mg of vitamin E and 500 mg of vitamin C daily for 15 weeks. The average ozone concentration during exercise was 77 microg/m3 (range, 14-186 microg/m3). After exclusion of subjects with insufficient compliance from the analysis, a difference in ozone exposure of 100 microg/m3 decreased forced expiratory volume in 1 second (FEV1) 95 ml (95% confidence interval (CI) -265 to -53) in the placebo group and 1 ml (95% CI -94 to 132) in the vitamin group; for forced vital capacity, the change was -125 ml (95% CI -384 to -36) in the placebo group and -42 ml (95% CI -130 to 35) in the vitamin group. The differences in ozone effect on lung function between the groups were statistically significant. The results suggest that supplementation with the antioxidant vitamins C and E confers partial protection against the acute effects of ozone on FEV1 and forced vital capacity in cyclists.