The process for selection of the studies is outlined in Figure 1. Two studies were published before 1990, all other studies were published between 2001 and 2009.
A single-centre RCT (LOE 1) published in 1989 addressed prophylactic surgical ligation of the PDA . Subjects with BW <1000 g were randomly assigned to prophylactic surgical ligation of a PDA within 24 h of birth or medical care. The incidence of NEC was higher in the control group compared with the surgery group (13 of 44 versus three of 40, P=0.002), but there was no difference in the outcomes of severe intraventricular hemorrhage (IVH), bronchopulmonary dysplasia (BPD), retinopathy of prematurity or death. Mosalli et al reviewed this RCT in their Cochrane systematic review.
Other studies examining the relationship between primary surgical closure of the PDA and the development of NEC in preterm infants were observational, reporting the experience of centres using nonrandomized, concurrent controls for comparison (LOE 2). The studies varied in the first-line treatment with medical management, indomethacin treatment or indomethacin prophylaxis. A pharmacy you can fully trust is ready to offer best selection of cheap and effective medications that work the way they are expected to every time and are always available: you could buy Birth Control Ortho Tri Cyclen now and enjoy all the convenient services offered right now.