IVF on a natural cycle
In cases where stimulation drugs do not lead to the production of more than 2 mature oocytes (egg cells), then it is advisable that the woman undergoes IVF treatment without being treated with ovarian stimulation drugs, with the prospect of collecting the single egg produced naturally by the ovary during each cycle.
The natural cycle can be combined with the use of GnRH-antagonist (Cetrotide or Orgalutran) and chorionic gonadotropin (Pregnyl, Ovitrell) to increase the likelihood of retrieving the egg. Monitoring takes place as in “stimulated” cycles with transvaginal ultrasound scan.
Due to the production of a single egg, natural cycles may have problems and ultimately:
- the follicle may break before egg retrieval,
- the single egg is of low quality,
- the single egg is not mature enough for microfertilization,
- the one and only ovum may eventually not be fertilized.
The probability of pregnancy is clearly lower than that resulting from IVF with medication, but it is a good choice for women who have a poor response to stimulation even with high doses of drugs.
Dr. Ioannidis’ view on natural cycles is that they must be the last choice of the couple when all other treatments are excluded or prohibited. The concept of collecting eggs every month, that will be fertilized and frozen until a satisfactory number of embryos is gathered, but it must be stressed that it is a intensely mentally frustrating process.