Prevention of preterm delivery with vaginal progesterone in women with preterm labour (4P): randomised double-blind placebo-controlled trial.

OBJECTIVE: To evaluate the effectiveness of 200 mg of daily vaginal natural progesterone to prevent preterm birth in women with preterm labour. DESIGN: Multicentre, randomised, double-blind, placebo-controlled trial. SETTING: Twenty-nine centres in Switzerland and Argentina. POPULATION: A total of 385 women with preterm labour (24(0/7) to 33(6/7) weeks of gestation) treated with acute tocolysis. METHODS: Participants were randomly allocated to either 200 mg daily of self-administered vaginal progesterone or placebo within 48 hours of starting acute tocolysis. MAIN OUTCOME MEASURES: Primary outcome was delivery before 37 weeks of gestation. Secondary outcomes were delivery before 32 and 34 weeks, adverse effects, duration of tocolysis, re-admissions for preterm labour, length of hospital stay, and neonatal morbidity and mortality. The study was ended prematurely based on results of the intermediate analysis. RESULTS: Preterm birth occurred in 42.5% of women in the progesterone group versus 35.5% in the placebo group (relative risk [RR] 1.2; 95% confidence interval [95% CI] 0.93-1.5). Delivery at <32 and <34 weeks did not differ between the two groups (12.9 versus 9.7%; [RR 1.3; 95% CI 0.7-2.5] and 19.7 versus 12.9% [RR 1.5; 95% CI 0.9-2.4], respectively). The duration of tocolysis, hospitalisation, and recurrence of preterm labour were comparable between groups. Neonatal morbidity occurred in 44 (22.8%) cases on progesterone versus 35 (18.8%) cases on placebo (RR: 1.2; 95% CI 0.82-1.8), whereas there were 4 (2%) neonatal deaths in each study group. CONCLUSION: There is no evidence that the daily administration of 200 mg vaginal progesterone decreases preterm birth or improves neonatal outcome in women with preterm labour.

Heart function in magnetic resonance imaging and the mesenteric artery reactivity in rats receiving lead-contaminated drinking water.

The aim of this study was to evaluate the effect of lead (Pb)-contaminated drinking water on magnetic resonance imaging (MRI)-estimated cardiac function, vascular reactivity, and serum lipids in rats. For 3 months, male Wistar rats, aged 4-6 weeks, were given drinking water with the addition of lead acetate at a concentration of 100 ppm Pb (10 rats) or water free from Pb (8 control rats). The cardiac MRI was performed at rest and under ß-adrenergic stimulation on a 4.7 T scanner using electrocardiogram-triggered gradient echo (FLASH) cine sequence. After 1-2 weeks of the MRI test, experiments were performed ex vivo. After stabilization of perfusion pressure (PP), norepinephrine at doses from 0.01 to 5.0 µg was dissolved in Krebs solution, injected in a volume of 100 µl, and next infused at a concentration of 0.5 µg/ml into the isolated mesenteric artery. In this manner, preconstricted mesenteric bed was used to determine PP changes induced by acetylcholine, given at doses from 0.05 to 5.0 µg, before and during the infusion of nitric oxide synthase inhibitor (1.0 µg/ml). At the end, dobutamine (5 mg), followed by potassium chloride (10.5 mg), was injected. Lipid levels were determined enzymatically, blood Pb level was measured by the atomic absorption spectrophotometer. This study showed that Pb impairs the left ventricular systolic and diastolic function. Pb-induced changes in response to resistance of vessels to vasoactive agents may be secondary to the reduced left ventricular ejection fraction. The high-density lipoprotein subfraction 2 (HDL2) is involved in the cardiovascular effect of Pb.

The epidemiology of life-threatening complications associated with reproductive process in public hospitals in Argentina.

OBJECTIVE: To analyse life-threatening obstetric complications that occurred in public hospitals in Argentina. DESIGN: Multicentre collaborative cross-sectional study. SETTING: Twenty-five hospitals included in the Perinatal Network of Buenos Aires Metropolitan Area. POPULATION: Women giving birth in participating hospitals during a 1-year period. METHODS: All cases of severe maternal morbidity (SMM) and maternal mortality (MM) during pregnancy (including miscarriage and induced abortion), labour and puerperium were included. Data were collected prospectively. MAIN OUTCOME MEASURES: Identification criteria, main causes and incidence of SMM; case-fatality rates, morbidity-mortality index and effective intervention's use rate. RESULTS: A total of 552 women with life-threatening conditions were identified: 518 with SMM, 34 with MM. Identification criteria for SMM were case-management (48.9%), organ dysfunction (15.2%) and mixed criteria (35.9%). Incidence of SMM was 0.8% (95% confidence interval [95% CI] 0.73-0.87%) and hospital maternal death ratio was 52.3 per 100 000 live births (95% CI 35.5-69.1). Main causes of MM were abortion complications and puerperal sepsis; main causes of SMM were postpartum haemorrhage and hypertension. Overall case-fatality rate was 6.2% (95% CI 4.4-8.6): the highest due to sepsis (14.8%) and abortion complications (13.3%). Morbidity-mortality index was 15:1 (95% CI 7.5-30.8). Use rate of known effective interventions to prevent or treat main causes of MM and SMM was 52.3% (95% CI 46.9-57.7). CONCLUSIONS: This study describes the importance of life-threatening obstetric complications that took place in public hospitals with comprehensive obstetric care and the low utilisation of known effective interventions that may decrease rates of SMM and MM. It also provides arguments that justify the need to develop a surveillance system for SMM.