Until what age can women use their own ovules?
- This is the starting point of the study presented by Dr. Marta Devesa, gynaecologist at Dexeus Women's Health, at the annual meeting of the ESHRE.
- Only 1.3% of in vitro fertilisation (IVF) procedures performed with the patient's own ovules in women over 44 have a successful outcome.
- In order to increase the success rate in women in this age group, the alternative is to opt for IVF with donor oocytes.
A study conducted and presented by Dr. Marta Devesa, gynaecologist at Dexeus Women's Health, at the annual meeting of the European Society of Human Reproduction and Embryology (ESHRE) shows that IVF cycles in women over 44 years using their own ovules have a success rate of only 1.3%.
According to the study, in women aged between 38 and 39 years, the rate of live births after IVF using their own ovules is 23.6%, falling rapidly as the patient ages: the success rate in women aged 40 to 41 is 15.6%, dropping as low as 6.6% in those between 42 and 43 years.
Dr. Devesa obtained these figures by reviewing 5,841 IVF treatment cycles conducted in 4,195 women, taking into account two main variables: the age of the patients and the number of oocytes retrieved in each case. This is the largest ever sample analysed to date to determine the percentage of live births in women over the age of 38; indeed, this study was conducted to make reliable predictions of the chances of success of this treatment in older patients.
"Not only do the findings support a well-known certainty, which is that female fertility deteriorates with age, but they also give us a clear and segmented overview of the extent to which fertility declines", Dr. Devesa explains. She adds: "We were able to see that this reduction in fertility is not as obvious in older patients who have opted to use donor ovules: in these cases, fertility levels remain similar regardless of age".
Age influences the quality of oocytes, but not the course of pregnancy.
The conclusion that can be drawn is that while the age of the patient has a critical impact on oocyte quality, it does not influence the course of pregnancy to the same extent; experts therefore recommend that patients over 44 opt for donated oocytes, as the chances of success with their own ones are scarce.
According to Dr. Devesa, the most likely biological reason for the fact that female fertility declines with age is the higher incidence of chromosomal abnormalities, which reaches up to 85% in the embryos of women over 42.
The study also shows that the cumulative ratio of live births was higher in cases where a surplus of embryos was available for cryopreservation, which indicates that the more oocytes the patient produces, the greater the success rate.
Therefore, in all age groups below 44 years, experts recommend taking into account both the mean IVF success rate for each age bracket and the number of oocytes retrieved in each patient before deciding whether to use own or donor oocytes.
According to Dr. Devesa, "scientific evidence shows that women aged 44 or over should be fully informed about their actual chances of a live birth and should be advised to resort to oocyte donation. This alternative is currently much more common in the US than in Europe, although Spain is one of the European countries where oocyte donation is the most widespread". According to the Spanish national registry system, 7,000 ovule donation cycles were performed in Spain in 2012.