Heparin therapy for complications of placental dysfunction: a systematic review of the literature.

OBJECTIVE: To assess the benefits and harms of antenatal antithrombotic therapy for women at risk of adverse pregnancy outcomes associated with placental dysfunction. SEARCH STRATEGY: PUBMED and the Cochrane Controlled Trials Register (CENTRAL) were searched. Reference lists of retrieved studies were searched by hand. No date or language restrictions were placed. Date of last search February 2008. SELECTION CRITERIA: Randomized controlled trials comparing antenatal antithrombotic therapy (alone or combined with other agents) with placebo or no treatment were considered. Cohort studies with an appropriate control group were also considered. Studies were evaluated independently for appropriateness for inclusion and methodological quality without consideration of their results. Our search strategy identified five case series, two cohort studies with a control group, and one randomized controlled trial. All of the case series and one of the cohort studies were excluded. DATA COLLECTION AND ANALYSIS: The methodological quality of the included studies was poor. There was considerable variation in methodology and the interventions. It was not appropriate to combine results in meta-analysis. MAIN RESULTS: From the randomized trial, heparin was not associated with a reduction in preterm birth less than 37 weeks gestation (Heparin 5/68 versus Control 7/39; relative risk (RR) 0.41; 95% confidence intervals (CIs) 0.14-1.20), or birth weight below 10th centile (Heparin 4/68 versus Control 6/39; RR 0.38; 95% CI 0.11-1.27). CONCLUSION: There is insufficient information to recommend the use of heparin during pregnancy for women at risk of complications due to placental dysfunction. Further information from randomized trials is required.

Comparison of impact of prenatal versus postnatal diagnosis of congenitally corrected transposition of the great arteries.

Congenitally corrected transposition of the great arteries (CCTGA) in the absence of major cardiac anomalies is thought to have a good outcome, although this has not been well documented. The objective of the present study was to compare the characteristics and outcomes of patients with a prenatal diagnosis of CCTGA to the characteristics and outcomes of those diagnosed postnatally. The optimal outcome was defined as intervention-free survival. All patients with CCTGA diagnosed prenatally and postnatally from 1999 to 2006 at 2 tertiary care institutions were reviewed. Patients with a single ventricle, heterotaxy, or valvar atresia were excluded. The differences between groups were assessed using the t test and chi-square test. A total of 54 patients (16 prenatal with 14 live born and 39 postnatal) were included. The patients diagnosed prenatally were diagnosed at a median gestational age of 20 weeks (range 16 to 37). Two deaths in each group were due to heart failure. The intervention-free survival rate for the prenatal and postnatal groups at 1, 6, and 36 months was 79%, 45%, and 30% and 85%, 61%, and 23%, respectively (p = NS). Of 37 patients, 14 (38%) underwent an arterial switch plus atrial baffling so that the morphologic left ventricle supported the systemic circulation, and 6 (16%) underwent repair of associated lesions so the morphologic right ventricle supported the systemic circulation; 4 (11%) of the 37 patients had pacemaker only. Prenatal patients with >1 fetal echocardiogram (12 of 14) did not have progression before birth. In conclusion, CCTGA has a >70% risk of intervention in the first 3 years after birth. The outlook is guarded and has an important effect on prenatal counseling.