title: The influence of IVF/ICSI treatment on human embryonic growth trajectories.
abstract: OBJECTIVE
  Is in vitro fertilization treatment with or without intracytoplasmatic sperm injection (IVF/ICSI) associated with changes in first and second trimester embryonic and fetal growth trajectories and birthweight in singleton pregnancies?
  
  
  CONCLUSIONS
  Embryonic and fetal growth trajectories and birthweight are not significantly different between pregnancies conceived with IVF/ICSI treatment and spontaneously conceived pregnancies with reliable pregnancy dating.
  
  
  BACKGROUND
  IVF/ICSI treatment has been associated with increased risks of preterm birth, fetal growth restriction and low birthweight. Decreased first-trimester crown-rump length (CRL) in the general population has been inversely associated with the same adverse pregnancy outcomes.
  
  
  METHODS
  In a prospective periconception birth cohort study conducted in a tertiary centre, 146 singleton pregnancies with reliable pregnancy dating and nonmalformed live borns were investigated, comprised of 88 spontaneous and 58 IVF/ICSI pregnancies.
  
  
  METHODS
  Serial 3D ultrasound scans were performed from 6 to 12 weeks of gestation. As estimates of embryonic growth, CRL and embryonic volume (EV) were measured using the I-Space virtual reality system. General characteristics were obtained from self-administered questionnaires at enrolment. Fetal growth parameters at 20 weeks and birthweight were obtained from medical records. To assess associations between IVF/ICSI and embryonic growth trajectories, estimated fetal weight and birthweight, stepwise linear mixed model analyses and linear regression analyses were performed using square root transformed CRL and fourth root transformed EV.
  
  
  RESULTS
  In 146 pregnancies, 934 ultrasound scans were performed of which 849 (90.9%) CRLs and 549 (58.8%) EVs could be measured. Embryonic growth trajectories were comparable between IVF/ICSI pregnancies and spontaneously conceived pregnancies (CRL: βIVF/ICSI = 0.10√mm; P = 0.10; EV: βIVF/ICSI = 0.03(4)√cm³; P = 0.13). Estimated fetal weight and birthweight were also comparable between both groups (βIVF/ICSI = 6 g; P = 0.36 and βIVF/ICSI = 80 g; P = 0.24, respectively).
  
  
  CONCLUSIONS
  Variations in embryonic growth trajectories of spontaneously conceived pregnancies with reliable pregnancy dating may partially be a result of less precise pregnancy dating and differences in endometrium receptivity compared with IVF/ICSI pregnancies.
  
  
  CONCLUSIONS
  The absence of a significant difference in embryonic and fetal growth trajectories suggests safety of IVF/ICSI treatment with regard to early embryonic growth. However, further research is warranted to ascertain the influence of IVF/ICSI treatments in a larger study population, and to estimate the impact of the underlying causes of the subfertility and other periconceptional exposures on human embryonic and fetal growth trajectories.
  This study was supported by the Department of Obstetrics and Gynaecology of the Erasmus MC, University Medical Centre.
  
  
  BACKGROUND
  No competing interests are declared.
authors.affiliation: Division of Obstetrics and Prenatal Medicine, Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands.
authors.forename: S C
authors.initials: SC
authors.lastname: Eindhoven
authors.affiliation: Division of Obstetrics and Prenatal Medicine, Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands.
authors.forename: E M
authors.initials: EM
authors.lastname: van Uitert
authors.affiliation: Division of Reproductive Medicine, Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands.
authors.forename: J S E
authors.initials: JS
authors.lastname: Laven
authors.affiliation: Division of Biostatistics, Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands.
authors.forename: S P
authors.initials: SP
authors.lastname: Willemsen
authors.affiliation: Division of Bioinformatics, Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands.
authors.forename: A H J
authors.initials: AH
authors.lastname: Koning
authors.affiliation: Division of Biostatistics, Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands.
authors.forename: P H C
authors.initials: PH
authors.lastname: Eilers
authors.affiliation: Division of Obstetrics and Prenatal Medicine, Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands.
authors.forename: N
authors.initials: N
authors.lastname: Exalto
authors.affiliation: Division of Obstetrics and Prenatal Medicine, Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands.
authors.forename: E A P
authors.initials: EA
authors.lastname: Steegers
authors.affiliation: Division of Obstetrics and Prenatal Medicine, Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands Division of Clinical Genetics, Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands r.steegers@erasmusmc.nl.
authors.forename: R P M
authors.initials: RP
authors.lastname: Steegers-Theunissen
mesh_terms: D000328:Adult; D047108:Embryonic Development; D005260:Female; D005307:Fertilization in Vitro / Q000009:adverse effects*; D047109:Fetal Development; D006801:Humans; D016014:Linear Models; D011247:Pregnancy; D011256:Pregnancy Outcome; D011446:Prospective Studies; D020554:Sperm Injections, Intracytoplasmic / Q000009:adverse effects; D016216:Ultrasonography, Prenatal
keywords: assisted reproductive technology; crown-rump length; embryonic volume; first trimester; virtual reality