Uterine position and fetal lung maturity in triplet and quadruplet pregnancy.
D005260:Female; D005325:Fetal Organ Maturity; D006801:Humans; D007746:Labor Presentation; D008168:Lung / Q000196:embryology*; D008297:Male; D011247:Pregnancy; D011272:Pregnancy, Multiple; D011783:Quadruplets; D014310:Triplets; D014599:Uterus