title: Discordant twins with the smaller baby appropriate for gestational age--unusual manifestation of superfoetation: a case report.
abstract: BACKGROUND
  Documentation of superfoetation is extremely rare in humans., The younger foetus has invariably been small for gestational age (estimated from the date of the last menstrual bleed) in all the cases reported in the literature. We report a case where the younger twin was of appropriate size for gestation.
  
  
  METHODS
  The first of twins was of 32 weeks gestation and the baby was of appropriate size and development for the gestational age. The second twin was of 36 weeks gestation. Gestational age was estimated with the New Ballard score, x-ray of the lower limbs, dental age on x-ray, and ophthalmic examination.
  
  
  CONCLUSIONS
  Bleeding on implantation of the first foetus probably helped demarcate the two pregnancies. Dental age and the New Ballard score can be used to diagnose superfoetation in discordant twins, when detailed first trimester ultra-sound data is not available.
authors.affiliation: Department of Pediatrics and Neonatology St Stephens Hospital, Tis Hazari, Delhi 110054, India. doc_noopur@yahoo.co.in <doc_noopur@yahoo.co.in>
authors.forename: Noopur
authors.initials: N
authors.lastname: Baijal
authors.forename: Mohit
authors.initials: M
authors.lastname: Sahni
authors.forename: Neeraj
authors.initials: N
authors.lastname: Verma
authors.forename: Amit
authors.initials: A
authors.lastname: Kumar
authors.forename: Nittin
authors.initials: N
authors.lastname: Parkhe
authors.forename: Jacob M
authors.initials: JM
authors.lastname: Puliyel
mesh_terms: D000328:Adult; D000365:Age Determination by Skeleton; D000366:Age Determination by Teeth; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D009460:Neurologic Examination; D011247:Pregnancy; D013476:Superfetation; D014429:Twins, Dizygotic; D016216:Ultrasonography, Prenatal