We have been noticing a recent influx of articles about an association between the number of eggs produced in an IVF cycle and the chances for a live birth. A recent study, upon which the articles have been based, looked at couples in the UK between 1991 and 2008 and found that when 15 eggs were retrieved, there was an ideal combination of high pregnancy rates with low instance of Ovarian Hyper-Stimulation Syndrome (OHSS), the negative ovarian reactions to too many medications. While this may be the case for the cases studied, it should be noted that these cases were conventional IVF cycles -- an important qualification that needs to be made for articles that are boldly stating an "ideal" number of eggs to be retrieved using IVF (should be, "for conventional IVF").
In addition, while it may be true that you can minimize the impact of hyperstimulation (used in conventional IVF) when ovaries are not stimulated to produce more than 15 eggs, you are still introducing unnecessary drugs and medications into the body that are impacting your organs, even if they are not necessarily causing OHSS. Using more progressive and advanced methods for IVF -- protocols like Minimal Stimulation and Natural IVF -- the ideal number of eggs for retrieval would not be 15. For Minimal Stimulation IVF, the number is closer to 3-5 eggs per cycle, and in a Natural IVF protocol, of course, the ideal number would be 1 egg. Indeed, the exciting aspect of advanced protocols like Minimal Stimulation and Natural IVF is that even with the lower yield of eggs, through closer monitoring, better technology, and more thoughtful decision making, we can get better results meaning that the pregnancy rates per egg retrieved is significantly higher.