Volume 179 - Issue 4
The effect of female age on the likelihood of a live birth from one in-vitro fertilisation treatment
Author: Nicholas A Tonti-Filippini
Med J Aust 2003; 179 (4): 220-221. || doi: 10.5694/j.1326-5377.2003.tb05510.x
Published online: 18 August 2003
Published online: 18 August 2003
Nicholas A Tonti-Filippini
Consultant Ethicist, 15 Alburnum Crescent, Lower Templestowe, VIC 3107. ntfATcyberspace.net.au.
To the Editor: Jansen’s study1 of the effect of maternal age on IVF outcome yields information that has not been available. However, the presentation of the data raises two questions.
Firstly, are the births reported all attributable to IVF intervention? A couple is considered infertile if they are unable to achieve conception after a year of unprotected intercourse, or the mother is unable to carry a pregnancy to a live birth.2 In reports of infertility, there is a natural conception rate of about 25%–30% per annum,3-6 and Jansen’s study, in effect, covers a 3-year period (or 4 years if you include the period for assessing the outcome of the pregnancies).
We need to know whether natural conception has contributed; whether the couples continued to have unprotected intercourse during the course of the study; and what means was used to identify a pregnancy as an IVF pregnancy (as distinct from a natural conception, if that distinction was made).
Jansen notes that there was a group of women who dropped out after treatments were initiated and before egg retrieval, and a further group for whom eggs could not be retrieved. It is unclear whether the former included those who had a natural conception. In terms of evaluating the success of IVF, more information on these groups would be valuable.
The second question relates to comparative embryo survival rates. Jansen gives the number of live births per egg retrieval procedure, and fresh and frozen embryo transfer is combined in the live-birth result. Separating live embryo transfer from frozen embryo transfer, which is done in the Victorian Infertility Treatment Authority annual reports 1998–2001, would indicate that the transfer of a fresh embryo has about a 9.5% chance of resulting in a live birth, and the transfer of a frozen embryo has about a 3.1% chance of resulting in a live birth. In the current discussion of embryos being available for research, this information about embryo survival rates would be informative.
Competing interests
I am a member of the Ethics Panel of the Victorian Infertility Treatment Authority.
References
- Jansen RPS. The effect of female age on the likelihood of a live birth from one in-vitro fertilisation treatment. Med J Aust 2003; 178: 258-261.
- Healy DL, Trounson AO, Andersen AN. Female infertility: causes and treatment. Lancet 1994; 343: 1539-1544. i1082805
- Hull MGR, Glazener CMA, Kelly NJ, et al. Population study of causes, treatment, and outcome of infertility. BMJ 1985; 291: 1693-1697. CBBJFIBF
- Templeton AA, Penney GC. The incidence, characteristics, and prognosis of patients whose infertility is unexplained. Fertil Steril 1982; 37: 175-182.
- Barnea ER, Holford TR, Mclnnes DRA. Long-term prognosis of infertile couples with normal basic investigations: a life-table analysis. Obstet Gynecol 1985; 66: 24-26.
- Rousseau S, Lord J, Lepage Y, Van Campenhout J. The expectancy of pregnancy for “normal” infertile couples. Fertil Steril 1983; 40: 768-772. i1082811