title: In vitro fertilisation and use of ovulation enhancers may both influence childhood height in very low birthweight infants.
abstract: BACKGROUND
  Term-born children conceived by in vitro fertilisation (IVF) are reportedly taller than naturally conceived (NC) children. High levels of growth promoting hormones and epigenetic imprinting have been suggested as pathogenetic mechanisms.
  
  
  OBJECTIVE
  Tall stature in prematurely born IVF-conceived (IVF-C) children suggests pre- or early implantation imprinting rather than a postnatal effect.
  
  
  METHODS
  We studied 334 very low birthweight (VLBW: birth weight <1500 g) children born prematurely during 1995-1999 and obtained their anthropometric measures at 6-10 years of age. Perinatal and neonatal data were obtained from the Israeli VLBW database. We compared IVF-C, ovulating agents conceived (OA-C) and naturally conceived (NC) groups of children with respect to their and their parents' anthropometry and their perinatal/neonatal variables.
  
  
  RESULTS
  Childhood height standard deviation scores (SDSs) were greatest in IVF-C (-0.12 (SD 1.25); p<0.022) and insignificantly greater in OA-C (-0.37 (SD 1.02)) as compared to NC (-0.58 (SD 1.36)) children. The IVF-C and NC groups were significantly different regarding 17 parental and perinatal variables; however, multiple regression analysis including these variables showed that, as compared with NC, IVF-C children had significantly older mothers at birth with earlier follow-up during pregnancy and more multi-fetal pregnancies.
  
  
  CONCLUSIONS
  IVF-C and to a lesser extent OA-C prematurely born children are taller than otherwise NC children. After ruling out postnatal and parental causes, we speculate that pre- or early implantation factors might have contributed to the taller stature of IVF-C children.
authors.affiliation: Department of Neonatology, Rambam Health Care Campus, Rambam Medical Center, Bat-Galim, Haifa, Israel. makhoul@rambam.health.gov.il
authors.forename: I R
authors.initials: IR
authors.lastname: Makhoul
authors.forename: A
authors.initials: A
authors.lastname: Tamir
authors.forename: D
authors.initials: D
authors.lastname: Bader
authors.forename: A
authors.initials: A
authors.lastname: Rotschild
authors.forename: Z
authors.initials: Z
authors.lastname: Weintraub
authors.forename: S
authors.initials: S
authors.lastname: Yurman
authors.forename: D
authors.initials: D
authors.lastname: Reich
authors.forename: Y
authors.initials: Y
authors.lastname: Bental
authors.forename: J
authors.initials: J
authors.lastname: Jammalieh
authors.forename: T
authors.initials: T
authors.lastname: Smolkin
authors.forename: P
authors.initials: P
authors.lastname: Sujov
authors.forename: Z
authors.initials: Z
authors.lastname: Hochberg
mesh_terms: D000886:Anthropometry; D001827:Body Height / Q000502:physiology*; D002648:Child; D002657:Child Development / Q000502:physiology*; D005260:Female; D005307:Fertilization in Vitro; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight / Q000254:growth & development / Q000502:physiology*; D008297:Male; D010062:Ovulation Induction; D017451:Receptors, Somatomedin / Q000502:physiology*
chemical_list: D017451:Receptors, Somatomedin