Terminology for In Vitro Fertilization (IVF)

The below is a new terminology for In Vitro Fertilization (IVF) as proposed by the International Society for Mild Approaches in Assisted Reproduction (ISMAAR) consensus group. Published in the journal of Human Reproduction, 2007.

Natural cycle IVF
The term Natural cycle IVF should be used when IVF is carried out with oocytes collected from a woman’s ovary or ovaries in a spontaneous menstrual cycle without administration of any medication at any time during the cycle.

Modified natural cycle IVF
When exogenous hormones or any drugs are used when IVF is being performed during a spontaneous cycle with the aim of collecting a naturally selected single oocyte but with a reduction in chance of cycle cancellation. This could include:
 (i) The use of human chorionic gonadotrophin (hCG)
(ii) The administration of gonadotrophin-releasing hormone (GnRH) antagonist

Mild IVF
When FSH or HMG is administered at lower doses, and/or for a shorter duration in a GnRH antagonist co-treated cycle, or when oral compounds (anti-estrogens, or aromatase inhibitors) are used  either alone or in combination with gonadotrophins. HCG injection and luteal support are also administered.

Conventional IVF
The following protocols can be considered:
(i) GnRH agonist is used for pituitary down-regulation followed by conventional doses of stimulation with FSH or hMG.
(ii) GnRH agonist is administered in a flare protocol with conventional doses of FSH or hMG.
(iii) GnRH antagonist is used with conventional doses and early start of FSH or hMG.

All of the above methods include the administration of hCG and luteal support.