Infertility is an extremely common problem that affects approximately 1 in 6 couples at some stage in their lives. The cause may be related to a problem with the man, the woman or both. In view of the intimate nature of the problem, there can be few conditions that cause such personal distress and embarrassment.

Assisted Reproductive Technologies (ART) are today largely established methods to rescue infertility problems. In conventional IVF, the gametes (ovocytes and sperm cells), once collected, are fertilized and cultivated for 2 to 5 days in an artificial culture medium in the embryology lab. Once a number of them have developed and reached the blastocyst stage when they are able to proceed to implantation inside the uterine cavity, they undergo a selection process by the embryologist and those that qualify as being of good enough quality are transferred into the uterus in variable numbers.

The traditional IVF process, although widespread, is still subject to limitations and, according to the European registries generated by the European Society of Human Reproduction and Embryology in 2003, the clinical pregnancy rates per transfer were 29.6%. Currently, measures taken to compensate for low rates of success of the procedure include strong hormonal stimulation (in order to obtain more ovocytes to begin the process with) and the transfer of more than one embryo (in order to increase the probability of implantation).

Although there are losses at every step of the process, the rate-limiting step is, in effect, the implantation. This step depends on a perfectly coordinated and synchronized process between the embryo and the uterus in which both the quality of the embryos and the receptivity state of the uterus play a determining role.

In terms of embryo quality, the success of IVF was initially compromised by sub-optimal culture conditions resulting in impaired embryo development and decreased embryo viability. Through the years, the in vitro techniques have made a lot of progress. Still, the culture media remain artificial and often incorporate a number of additives that are absent from the uterine cavity. More importantly, the laboratory context misses all of the biological interactions between the developing embryos and the maternal organism.

Given the importance of the environment in which the very first stages of development take place, and the existence of animal data showing that exposure of embryos to different culture conditions can alter the expression and imprinting of a number of key genes^2,3,4,5, it is paramount to try to replicate, in the lab, the physiologic composition found in the natural environment. However, there have been next to no studies investigating the impact of different culture media on chromosomal normality and the architecture of the mitotic spindle⁶.

In the ANECOVA approach, the zygotes are placed in the maternal uterine cavity over all early development stages to get the benefits of a customized and adapted environment. (see also section: in vivo development by Anecova)