Types

There are 2 main types of EFS – Genuine Empty follicle syndrome (GEFS) and False Empty follicle syndrome (FEFS).
Genuine Empty follicle syndrome is defined as failure to retrieve oocytes from mature follicles apparently after Controlled Ovarian stimulation for IVF. It may be due to dysfunctional folliculogenesis, the oocytes fail to retrieve even with normal follicular development & steroidogenesis in presence of optimal beta human choriogonadotrophin (bhCG) levels on the oocyte retrieval.
False Empty follicle syndrome (FEFS) is defined as failure to retrieve oocytes in presence of low beta human choriogonadotrophin hormone (bhCH) level on the day of oocyte retrieval. It is basically due to human errors or pharmaceutical reasons.

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