The purpose of this study is to evaluate the effectiveness of a modified natural cycle in patients with previous poor response to infertility drugs and high basal FSH, prior to proceeding to oocyte donation or abandoning fertility treatment.

Poor responders are a diverse group of IVF patients who fail to respond to IVF drugs. In these patients pregnancy rates remain disappointingly low and usually oocyte donation is their only viable option. The need for lengthy ovarian stimulation regimes can be avoided by performing IVF during a natural menstrual cycle. However, the main problem with a natural cycle is that successful IVF outcome can be compromised by a premature LH surge. This problem can be solved by the administration of GnRH antagonists that suppress endogenous gonadotropin levels, comprising a modified natural cycle (MNC). Previous studies have shown that MNC offers no realistic chances of pregnancy prior to oocyte donation. In this study we will re-assess this view by showing that MNC offers some, albeit small, chances of positive IVF outcome in patients with known previous poor response prior to oocyte donation.

Inclusion Criteria:

• Regular menstrual cycle (21-35 days)
• Basal FSH>12 IU/ml
• One or more failed IVF attempts (<3 oocyte retrieved)

Exclusion Criteria:

• PCOS
• Normal responders

Women undergoing IVF treatment