Newborn RDS in the twin arm is defined as compatible symptoms with radiographically confirmed hyaline membrane disease or with respiratory insufficiency of prematurity requiring ventilator support. Data expressed as mean n(%),Odds ratio, CI, and P-value were determined using repeated measures model wherein each twin/triplet within a given pregnancy is considered a repeated measure. Exceptions are comparison with 0 outcomes in one or both groups, so Fisher's Exact Test was used. Morbidity measures were based on live births with data available for the outcomes.

Supplemental oxygen use by the baby measured at the point that the baby reaches 28 days old (after birth)within the twin group.

Newborn Sepsis in the twin group was defined as the presence of positive blood culture obtained in the first week of life in association with clinical findings suggesting illness for which the neonate received antibiotics.

Newborn Pneumonia in the twin group is described as compatible symptoms with diagnostic radiograph findings and positive results on blood cultures, persistent leukopenia

Newborn Intraventricular hemorrhage (IVH) Stage III in the twin group is described as - IVH with ventricular dilatation. Neonatal Intraventricular hemorrhage (IVH)Stage IV in the twin group is described as - IVH with parenchymal extension.

Newborn Periventricular leukomalacia (PVL) in the twin group is described as the presence of more than 1 obvious hypo echoic cyst in the periventricular white matter.

Newborn NEC in the twin group is described as the presence of any of the following: (1)unequivocal intramural air in abdominal radiograph; (2) perforation abdominal radiograph; (3) clinical evidence of perforation (erythema and induration of the abdominal wall or intrabdominal abscess formation); (4) characteristic findings observed at surgery or autopsy; (5) Stricture formation after an episode of suspected necrotizing enterocolitis.

Newborn ROP within the twin group is described as retinopathy confirmed on fundoscopic examination, felt to be due to prematurity and subsequent oxygen therapy.

Newborn Asphyxia or Hypoxic-ischemic encephalopathy (HEI) within the twin group is characterized by clinical and laboratory evidence of acute or subacute brain injury due to asphyxia (ie, hypoxia, acidosis).

Perinatal death within the twin group is described as a stillbirth, neonatal death, or miscarriage after randomization.