eprintid: 10144864
rev_number: 14
eprint_status: archive
userid: 699
dir: disk0/10/14/48/64
datestamp: 2022-05-13 09:01:19
lastmod: 2022-05-13 09:01:19
status_changed: 2022-05-13 09:01:19
type: thesis
metadata_visibility: show
sword_depositor: 699
creators_name: Williams, Caroline Lucy
title: A population-based linkage of administrative data sources to investigate associations between assisted reproductive technology and cancer risk in Great Britain
ispublished: unpub
divisions: UCL
divisions: G25
divisions: D13
divisions: B02
note: Copyright © The Author 2022. Original content in this thesis is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) Licence (https://creativecommons.org/licenses/by-nc/4.0/). Any third-party copyright material present remains the property of its respective owner(s) and is licensed under its existing terms. Access may initially be restricted at the author’s request.
abstract: Introduction: 
Exposure of women to supra-physiological hormone levels and exposure of early embryos to artificial environments could increase cancer risks in women who have had assisted reproductive technology (ART) and children born after ART. This study aims to investigate possible associations by linking routinely collected data.  
Methods:
Records of 255,786 ART treated women and 106, 013 ART conceived children in Great Britain (1991-2010) were linked to national registries of England & Wales and of Scotland, and the National Register of Childhood Tumours to obtain cancer outcome status. Observed cancers were compared against age and sex specific expectation, based on national rates. Analyses were stratified for potential moderating, mediating and confounding factors; 95% confidence-intervals, 2-sided P-values and trends were calculated assuming a Poisson distribution.
Results:
In 2,257,789 person-years of observation in ART treated women with an average follow-up of 8.8 years, no increased risk of corpus uteri (SIR-1.12; 95%CI 0.95-1.30), or invasive breast (SIR-0.96; 0.2-1.00) cancer was detected. An increased risk of ovarian cancer (SIR-1·39; 1·26-1·53), both invasive (SIR-1·40; 1·24-1·58) and borderline (SIR-1·36; 1·15-1·60) was limited to women with endometriosis, nulliparity, or both.  There was no increased risk of ovarian tumours in women treated for only male factor or unexplained infertility. In 700,705 person-years of observation in ART conceived children with an average follow-up of 6.6 years, no overall increased risk of childhood cancer was found (SIR-0.98; 0.81-1.19). An excess of hepatoblastoma (SIR-3.64; 1.34-7.93), was likely mediated by low-birthweight (Birthweight<2500g SIR-10.29; 3.34-24.02). 


Conclusion:
Routinely collected national data, linked to investigate cancer outcomes after ART, were largely reassuring, although some specific increases were detected. There was no convincing evidence relating increased risks to ART procedures per se. Average follow-up was 8.8 years for women and 6.6 years for children, therefore longer follow-up is required to confirm impact on lifetime risks.
date: 2022-03-28
date_type: published
oa_status: green
full_text_type: other
thesis_class: doctoral_open
thesis_award: Ph.D
language: eng
primo: open
primo_central: open_green
verified: verified_manual
elements_id: 1944107
lyricists_name: Williams, Caroline
lyricists_id: CLWIL03
actors_name: Williams, Caroline
actors_id: CLWIL03
actors_role: owner
full_text_status: public
pagerange: 1-330
pages: 330
institution: UCL (University College London)
department: Institute of Child Health
thesis_type: Doctoral
citation:        Williams, Caroline Lucy;      (2022)    A population-based linkage of administrative data sources to investigate associations between assisted reproductive technology and cancer risk in Great Britain.                   Doctoral thesis  (Ph.D), UCL (University College London).     Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10144864/13/Williams_10144864_Thesis_redacted.pdf