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.

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.

Acetohydroxyacid synthase (AHAS) in vivo assay for screening imidazolinone-resistance in sunflower (Helianthus annuus L.).

The objective of this work was to evaluate the in vivo acetohydroxyacid synthase (AHAS) activity response to imidazolinones and its possible use as a selection method for evaluating AHAS inhibitor resistance. In vivo AHAS assay and the comparison of parameters from dose-response curves have been used as a valid tool for comparing sunflower lines and hybrids differing in imidazolinone resistance. The sunflower resistant genotypes evaluated here were 100-fold and 20-fold more resistant compared with the susceptible line for imazethapyr and imazapyr, respectively. This assay also allowed discrimination of homozygous from heterozygous genotypes for I(mr1) locus that codify for the catalytic subunit of AHAS. The in vivo AHAS assay described in this study was useful for the selection of sunflower genotypes differing in herbicide resistance and could be a useful tool when breeding for imidazolinone resistance in sunflower.