Nearly 60% of IVF procedures in the United States are performed on women 35 and older.
They may be subject to embryo cryopreservation for later use if IVF procedures have resulted in more embryos than is currently needed.
The resulting embryos are then transferred to the uterus through the normal IVF procedure.
All insurance companies in New York pay for diagnosis and many cover drugs, but few pay for IVF procedures.
It is thought that this is due to genes being turned on or off by the IVF procedures.
The researchers used these findings to call for more attention to the effective transfer of embryos during IVF procedures.
There may be leftover embryos or eggs from IVF procedures if the woman for whom they were originally created has successfully carried one or more pregnancies to term.
The estimated $30 million to $40 million market in IVF procedures has medical entrepreneurs interested, especially since insurers are starting to pick up some of the costs.
For the IVF procedure to work, eggs must be removed when they are fully mature, whatever the hour.