More WA couples are getting permission to store their frozen embryos beyond the normal 10-year limit, figures show.
In-vitro fertilisation experts say the trend is likely to increase as more couples grapple with the dilemma of whether they will want more children later and others put off the difficult decision to discard their embryos.
The Reproductive Technology Council's latest annual report reveals some embryos are being kept on ice up to 15 years.
In the last financial year, it approved 30 applications for couples to store their embryos beyond 10 years - almost double the 16 approvals in 2011-12.
Most get permission to store for an extra two or three years.
It also approved one application to store gametes - eggs and sperm - for a total of 25 years, which is 10 years longer than the normal 15-year limit.
Before 2004, embryos could be stored for only three years, but regulations were changed because couples wanted more time to use them.
As of June, 18,455 embryos were in storage, compared with 17,312 in June last year.
Just over 1000 were discarded in the past year.
Professor Roger Hart, of the IVF unit Fertility Specialists of WA, said to "allow an embryo to succumb" was incredibly difficult so many couples wanted to postpone that decision.
Extending the storage time let them leave options open, including using the embryos themselves or donating them to another couple.
The RTC report shows 3638 WA women had IVF in 2012-13, a one per cent rise on the previous year.
But the number of fresh egg treatment cycles fell for the first time in WA, from 5575 to 5483.
Experts believe that fall may reflect the better success rate of IVF, which meant couples needed fewer attempts for success.
But some doctors point to reduced Medicare funding for IVF after caps were introduced in 2010.