In vitro mat­u­ra­tion of human oocytes can be used for fer­til­ity preser­va­tion. In vitro maturation-IVM indi­cates that eggs are retrieved with­out stim­u­la­tion or after a short period-about 3 days-of treat­ment with fer­til­ity med­ica­tion. Oocytes are then either 1. Frozen as imma­ture eggs, 2. Matured in the lab for 24 to 30 hours and then frozen as mature eggs or 3. matured in the lab and fer­til­ized using direct injec­tion of sperm-ICSI and the result­ing embryos as frozen. Freez­ing mature eggs gen­er­ally yields bet­ter out­comes that freez­ing imma­ture eggs. Vit­ri­fi­ca­tion appears to result in bet­ter sur­vival than slow freez­ing of oocytes.

Advan­tages of in vitro mat­u­ra­tion

IVM can be accom­plished with­out pro­longed expo­sure to fer­til­ity medication-3 days ver­sus 14 to 21 days for clas­sic IVF cycles.  Estro­gen does not increase to the same lev­els as seen with IVF, which may be advan­ta­geous for some estro­gen sen­si­tive can­cers as breast can­cer. Newer approach to ovar­ian stim­u­la­tion using aro­matase inhibitors in women diag­nosed with breast can­cer, enables ovar­ian stim­u­la­tion to pro­ceed with­out marked increase in estro­gen lev­els. Because less fer­til­ity med­ica­tion are used, the cost and the risk for ovar­ian hyper­stim­u­la­tion syn­drome are less than con­ven­tional IVF

Dis­ad­van­tages of in vitro maturation

As a repro­duc­tive endocri­nol­o­gist attempt to retrieve eggs from small imma­ture fol­li­cles, he or she is suc­cess­ful in doing so 50% of the time-approximately five eggs are retrieved from 10 fol­li­cles. Fur­ther­more, 70 to 80% of those com­plete mat­u­ra­tion in the lab mak­ing the process much less effi­cient than IVF. Very few labs in the world reported con­sis­tent suc­cess with IVM and only in select patients-those with high ovar­ian reserve. Research is ongo­ing to improve our abil­ity to com­plete mat­u­ra­tion of eggs in the lab. The suc­cess of this method is how­ever, lim­ited by woman’s ovar­ian reserve and our abil­ity to retrieve these imma­ture eggs. IVM is more suit­able for women with PCOS or large num­ber of small fol­li­cles in the ovary.

Safety of in vitro maturation

A rel­a­tively small num­ber of babies were borne world­wide using IVM. There are no long term data on the health of chil­dren con­ceived using IVM. More­over, data on out­comes are very scarce on babies borne after both IVM and egg freez­ing. One study showed that babies born after IVM are larger than those con­ceived with IVF and more fre­quently required cesarean deliv­ery. Long term neu­ro­log­i­cal out­comes are still unknown.

In vitro Mat­u­ra­tion of imma­ture oocytes after a con­ven­tional IVF cycle can be per­formed, aim­ing at increase the egg yield. After stim­u­la­tion with fer­til­ity med­ica­tion for 10–14 days, eggs are retrieved. Mature eggs are fer­til­ized with sperm and imma­ture eggs are left in cul­ture to mature-instead of dis­card­ing them. Imma­ture eggs are left over oocytes and in the expe­ri­ence of many labs sel­dom pro­duce a good qual­ity embryo or pregnancy.

In select patients with good ovar­ian reserve, in vitro mat­u­ra­tion can be con­sid­ered after coun­sel­ing patients that this so far a less effi­cient approach than IVF and that the long term out­comes of chil­dren con­ceived via IVM is still unknown. Read more at http://nycivf.org