Still no strong evidence that adjunctive treatment with human growth hormone in IVF improves results
Helsinki, July 4, 2016: Despite its occasional use as an adjunct in IVF, human growth hormone appears of little benefit to women having difficulty conceiving. Indeed, in an Australian/New Zealand collaborative placebo-controlled randomised trial presented here at the Annual Meeting of ESHRE, live birth rates were no better in poor-responding patients (under the age of 41) given growth hormone as a supplement than in those given placebo.
Most studies on the subject, said investigator Professor Robert Norman from the Robinson Research Institute at the University of Adelaide, and FertilitySA, Australia, "do not address the most important clinical outcome our patients require, that of delivering a live healthy infant", although some studies — many of them small — do reflect a trend towards improved clinical pregnancy outcome. A recent Cochrane review found that, while human growth hormone did not improve results in routine IVF, there is "some evidence of increased pregnancy and birth rates in women who are considered 'poor responders' to IVF."(1) The end point of this study in Helsinki is indeed live birth rate, and, despite the suggestions of the smaller studies, there was still no strong evidence found for a growth hormone advantage.
The study, to achieve sufficient statistical power for a strong conclusion, required an enrolment of 390 women recruited from fertility centres in Australia and New Zealand, but after four years only 136 had been recruited — partly because many prospective recruits had bought growth hormone outside the trial. Those who were recruited all met predefined criteria for poor response — a previous IVF cycle with no more than five eggs collected after maximum stimulation — and each had ovarian stimulation with same previous drug dose.
Results showed a clinical pregnancy rate of 14% in the growth hormone group and 11% per started cycle in the placebo group. There were equal comparisons between the two groups in the number of eggs collected, quality of embryos and duration of treatment. Most patients, as is the norm in Australia, had a single embryo transfer.
Commenting on the results, Professor Norman agreed that they still offer no strong evidence of a real benefit for poor responders in IVF and said that could only be achieved by an "extremely large" randomised trial. Earlier studies which did find a benefit, he added, had smaller numbers, were not placebo-controlled, and had pregnancy and not live birth end points.
The implication of the ESHRE results, said Professor Norman, is still that there is no evidence of a benefit — or lack of benefit — in giving supplementary growth hormone to poor responders in IVF. "If it were cheap," he said, "it might find a place in poor responders, but normal doses cost more than USD 1000."
Poor responders are a "notoriously difficult" group to treat, said Professor Norman, adding that many strategies have been tried — including human growth hormone — but there is no solid evidence that any of them improve live birth rates. He noted that up to 30% of patients who respond poorly to treatment with poor pregnancy rates are over 40 years of age.
Abstract O-082, Monday 4 July 2016, 15.30
A randomised double blind placebo controlled study of recombinant human growth hormone (r-HGH) on live birth rates in women who are poor responders
1. Ahmad G, Brown J, Duffy JM, et al. Growth hormone for in vitro fertilization. Cochrane Database Syst Rev. 2009: CD000099.
2. Poor responders represent a common and challenging group of patients in IVF. They are defined by an inadequate response to ovarian stimulation such that too few follicles mature during treatment and too few (and/or of too poor quality) embryos are produced. Thus, a healthy patient might produce 12 eggs following ovarian stimulation (even with low doses), but a poor responder as few as two or three. Ovarian reserve testing before treatment may give an indication of likely response, as will age.
3. Growth hormone as an adjunct to ovarian stimulation has been used for several years (particularly in the USA), and more so in recent years as its price reduced.
- A podcast of Professor Norman speaking about this study is available at https://www.eshre2016.eu/Media/Press-releases/Norman/Podcast.aspx
- When obtaining outside comment, journalists are requested to ensure that their contacts are aware of the embargo on this release.
For further information on the details of this press release, contact:
Christine Bauquis at ESHRE
Mobile: +32 (0)499 25 80 46
Email: [email protected]