Women With More Severe Endometriosis Have Fewer Eggs

However, this does not affect their rate of fertilization.

Key Points

Highlights: 

• The stage of endometriosis affects ovarian response and the quality of oocytes and embryos but not fertilization rates.

Importance:

• Appropriate ways of managing women with advanced endometriosis may be necessary.

What's done here:

• The number and quality of oocytes and embryos and the rate of fertilization in women with and without endometriosis who underwent intracytoplasmic sperm injection were analyzed.
• A total of 440 women (220 had endometriosis, 220 did not have the disease) were evaluated.

Key results:

• The number of retrieved oocytes was significantly lower in women with advanced endometriosis (stage 3 or 4) compared to women with minimal or mild disease or controls.
• The size of the oocytes retrieved from women with advanced endometriosis was smaller compared to other women.
• Fewer mature oocytes were retrieved from women with advanced endometriosis.
• The total number of embryos was smaller in women with advanced endometriosis.
• The fertilization rate was similar among all women.

Limitations:

• This was a single-center retrospective study.

Lay Summary

Severe endometriosis negatively affects ovarian response and the quality of oocytes and embryos, according to a new study published in JBRA Assisted Reproduction. However, the rate of fertilization does not seem to be affected by endometriosis stage. 

These findings could help clinicians find appropriate methods of managing advanced endometriosis, according to the authors of the study.

In order to explore whether the stage of endometriosis affects the outcomes of intracytoplasmic sperm injection in infertile women who have not previously had ovarian surgery, a team of researchers from Babol University of Medical Sciences in Iran led by Dr. Parvaneh Mirabi analyzed a total of 440 women. Of these, 220 had endometriosis while 220 did not have the disease. They then divided women with endometriosis into four groups based on the stage of their disease.

The researchers analyzed the women’s clinical and laboratory parameters and ovarian reserve markers as well as the number and quality of oocytes and embryos and the rate of fertilization.

The results showed that women with advanced endometriosis (stage 3 or 4 according to the American Society for Reproductive Medicine – ASRM) had significantly fewer retrieved oocytes compared to women with less severe disease and women who were infertile due to other reasons. 

Moreover, the retrieved oocytes were smaller in size and fewer of them were in the metaphase 2 stage, i.e. more mature in women with advanced endometriosis. The total number of embryos generated using these oocytes was also lower compared to oocytes obtained from women with less severe diseases or those who were infertile due to other reasons.

However, the researchers found that the rates of fertilization between women with severe endometriosis and women with minimal or mild endometriosis and controls were similar.

“Based on the results of this study, we suggest that the high stage of endometriosis may damage ovarian reserve, and it has a detrimental effect on ovarian response during gonadotropin stimulation,” the researchers concluded.

Research Source: https://pubmed.ncbi.nlm.nih.gov/36350241/