Hum. Reprod. Advance Access published online on September 25, 2009
Human Reproduction, doi:10.1093/humrep/dep335
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Incidence of retinoblastoma in Dutch children conceived by IVF: an expanded study
1 Department of Ophthalmology, VU University Medical Center, de Boelelaan 1117, 1007 MB Amsterdam, The Netherlands 2 Department of Clinical Genetics, VU University Medical Center, de Boelelaan 1117 1007 MB Amsterdam, The Netherlands 3 Department of Ophthalmology, University Medical Center Utrecht, Heidelberglaan 100 3584 CX Utrecht, The Netherlands 4 Department of Paediatric Oncology, VU University Medical Center, de Boelelaan 1117 1007 MB Amsterdam, The Netherlands 5 The Institute for Research in Extramural Medicine (EMGO), VU University Medical Center, Van der Boechorststraat 7 1081 BT Amsterdam, The Netherlands 6 Department of Epidemiology, the Netherlands Cancer Institute, Plesmanlaan 21 1066 CX Amsterdam, The Netherlands
7 Correspondence address. E-mail: t.marees{at}vumc.nl
BACKGROUND: In 2003, we reported an increased risk of retinoblastoma in children conceived by IVF between 1995 and 2002. However, population-based studies among children conceived by IVF did not find an elevated risk of retinoblastoma.
METHODS: From nationwide estimates of numbers of live births conceived by IVF (n = 40 330), we estimated the expected numbers of patients with retinoblastoma conceived by IVF in the period 1995–2007. The observed number of retinoblastoma diagnoses in children conceived by IVF was obtained by questionnaires sent to the parents of children with retinoblastoma diagnosed between 1995 and 2005. For non-responders and patients diagnosed after 2005, information was available through the medical files, in which information on fertility treatment has been routinely recorded since 2000. The relative risk (RR) of retinoblastoma among children conceived by IVF was calculated for the total study period (1995–2007) and for the expanded study period (2002–2007).
RESULTS: Of all eligible patients with retinoblastoma (n = 162) diagnosed in the period 1995–2007, seven were conceived by IVF. In the total study period (1995–2007) the risk was significantly elevated [RR = 2.54, 95% confidence interval (CI) = 1.02–5.23]. In the expanded study period (2002–2007), no significantly elevated risk (RR = 1.29, 95% CI = 0.16–4.66) was found.
CONCLUSIONS: We found a significantly increased risk of retinoblastoma in children conceived by IVF in the total study period 1995–2007. However, this increased risk was mostly based on the much stronger risk increase observed previously, for 1995–2002. Caution and awareness on the one hand and avoiding unnecessary worries on the other hand are important at this stage of our knowledge.
Key words: retinoblastoma/IVF/the Netherlands/ICSI
Submitted on May 29, 2009; resubmitted on August 21, 2009; accepted on August 25, 2009.