Michalis Kyriakidis, MD, MSc,
Assisted Reproduction Gynaecologist, Embryolab Associate Scientific Director

Major strides have been made over the last decades to render assisted reproduction methods more successful and more patient-friendly. It is now evident that the effectiveness of IVF is greatly associated with ovarian stimulation response and the number of recruited eggs.

These days, the most common approach is the pharmaceutical stimulation of the ovaries, based on the rationale that response depends on the dose of the pharmaceuticals administered. Evidently, the aim is to increase the likelihood of success by increasing the number of eggs collected. Indeed, it seems that the ideal result is produced when a couple collects an adequate number of eggs and embryos.

In spite of this, a high percentage of women present diminished ovarian reserve and a low number of eggs. This group of women will not respond excessively to ovarian stimulation, despite the high doses of pharmaceutical treatment that may be used. The best alternative for these women is to combine mild stimulation cycles with embryo collection.

The term “mild stimulation” refers both to the low-dose pharmaceutical treatment and the restriction of the hormonal burden during the treatment cycle. During these cycles, pharmaceutical treatment depends on the special traits of each woman and may include anything-from stimulating pills to injections. For almost the past two decades, literature has linked mild-stimulation protocols to the collection of better quality eggs and higher pregnancy rates. It is possible that a homogeneous good-quality group of eggs may be due either to the best natural selection by the ovary or to the lowest exposure to stimulating drugs. The benefit of mild-stimulation protocols is not only limited to the characteristics of the eggs, but also extends both to the hormonal environment of the uterus and to the implantation process. There are adequate data available presently for the clinical effectiveness of mild stimulation at levels comparable to conventional ovarian stimulation. However, the small number of available embryos is a restricting factor which does not allow the couple to maintain a stock.

The daily use of new technology nowadays, such as pre-implantation diagnosis, has created the need for a larger stock of embryos. Therefore, this limitation of mild protocols may be addressed with the collection of embryos during different cycles of the woman. Women with diminished ovarian reserve or high reproductive age will be especially benefited by the systematic collection of eggs or embryos. Being aware of the significant developments in cryobiology and the safety of cryopreservation methods, it becomes evident that embryo collection is a viable alternative.

So, combining mild-stimulation protocols with the collection and cryopreservation of embryos is quite a successful strategy these days. Of course, it must be adapted to the special traits and wishes of the couple. However, it remains an effective alternative and a useful tool in achieving our goal to create a family.