By I.Soussis MD
Egg donation is a fantastic tool in our hands, that allows us to explore how endometriosis affects the results of IVF.
Its action is through the endometrium or through the quality of the oocytes and subsequently through the quality of the produced embryos?
In trying to answer the question two different approaches have been taken:
1. The eggs of the same donor were shared by two recipients. One recipient is healthy and the other suffers from endometriosis. Data was prospectively collected and the pregnancy rates between the two groups compared.
2. Retrospective studies with oocyte donation cycles, in which a recipient became pregnant and the other not. The data was analyzed according to the cause of infertility. We also examined the origin of the eggs and compared the pregnancy rates between recipients, receiving ova from donors with endometriosis or without endometriosis.
Diaz et al 2000, from the Valencia Infertility Institute IVI IVF studied 58 recipients. Of these 25 were suffering from severe endometriosis stage III and IV. The remaining 33 recipient did not suffer from endometriosis. Both groups of women followed the same preparation of the endometrium, prior to embryo transfer. The number of fertilized eggs, of transferred embryos, the pregnancy rates and abortion rates were similar in both groups. So severe endometriosis does not affect pregnancy rates when the eggs come from healthy donors.
Similar results were reported from 444 egg donation cycles in 222 recipients from Bodri et al 2007.
Simon et al. 1994 again from I.V.I IVF retrospectively examined 178 embryo transfers into 141 recipients. Significantly lower pregnancy rates were found in women who received oocytes from donors with endometriosis.
To further investigate the influence of endometriosis on the endometrium or the egg, the same group of scientists in Spain, organized a prospective study Pelicer et al 1994.
Patients were divided into three groups. A: 44 donors without endometriosis who gave eggs to healthy recipients, B: 14 donors with endometriosis who gave eggs to healthy recipients, and C: 16 donors without endometriosis donated to recipients with endometriosis.
Significantly lower embryo implantation rates were observed in group B 6.8% versus 20.1% A and 20.8% C.
Significantly lower rates of pregnancy were observed in group B 28.6% vs. 61.4% A and 60% C.
In agreement with the mentioned studies, analysis of the results of egg donation in our IVF Unit in Athens, IVF & Genetics, showed that the recipients with endometriosis have excellent pregnancy rates of 60%.
1. Pregnancy rates after oocyte donation in recipients with endometriosis are excellent, when the eggs originate from donor without endometriosis and they can reach 61.4%.
2. Pregnancy rates after oocyte donation are lower than expected, even in healthy recipients, when the eggs originate from donors with endometriosis.
3. Endometriosis affects the quality of the eggs.