A pilot study to assess low dose ovarian stimulation using local anaesthetic to collect oocytes for women having IVF treatment

None listed

In the last 5-10 years there have been major advances in the technology and knowledge of assisited reproductive technology treatments. These include improved media and control of the environment for culturing human embryos. As a result there have been significant improvements in pregnancy rates and a significant increase in the transfer of a single embryo, to prevent the complications associated with multiple pregnancy. Historically, pregnancy rates have increased with greater numbers of eggs collected. Therefore superovulation procedures designed to enable the collection of 10-15 eggs per IVF cycle were a required part of the treatment strategy. However, with the recent advances of improved embryology techniques and pregnancy rates the requirement for a large number of eggs to be collected from young women has reduced. Modelling from our own laboratory has shown that pregnancy rates in young women plateau at 3-4 eggs. Therefore in this group of women production of more than four eggs in a stimulated cycle does not increase pregnancy rates but are associated with the risk of complications such as ovarian hyperstimulation syndrome (OHSS) (Reviewed in Verberg et al., 2009). Futhermore, there is increasing evidence in both animal models and also in the human that there are increased benefits of low dose stimulation. High doses of stimulation are associated with increased rates of poor quality oocytes and embryos (Valbuena et al., 2001) and have been reported to affect endometrial competence as well as reportedly increasing the incidence of aneuploidy (Baart et al. 2007). As a result of this new information, there has been the development of a more physiological style of ovarian stimulation in IVF for good prognosis patients, involving very low dose stimulation coupled with high quality embryology. These protocols are designed to produce a small number of eggs (aim 3-4 eggs) which can be fertilised, cultured and the best embryo transferred. As the literature presents such diverse findings we are initiating a pilot case-matched study to establish the efficacy of and patient feedback of tolerance to minimal stimulation regimes in an IVF cycle. Therefore, this pilot study is designed to assess the outcome of a low dose minimal stimulation treatment regime in a selected group of women undergoing IVF treatment.An interim analysis will be conducted after 10 cycles and if significant problems are identified, or average oocyte retrieval rates are below 2 eggs, the study will be abandoned at that point.