In a new study published in the Journal of Endocrinology, embryologist Dr. Yanguang Wu challenged the assertion that it’s women’s declining egg quality that prevents IVF from being more successful for women over 40 years of age. Dr. Wu found that aging of the eggs’ environment is the problem, not aging of the eggs themselves
The researcher team compared the reproductive tissue of egg donors aged 21-29, 30-37 and 43-47 years. Compared with egg donors aged 21-29 and 30-37, those aged 43-47 had reduced growth and multiplication of granulosa cells, the cells that support the oocytes inside a woman’s ovary and aid their growth.
Further investigation revealed that the granulosa cells of the older women produced fewer cell receptors for follicle-stimulating hormone (FSH), but produced more receptors for luteinizing hormone (LH) and progesterone. These changes in hormone sensitivity mean older women are significantly more likely to experience early luteinization, which prevents the ovaries from maturing oocytes and preparing the womb for pregnancy.
The team explains that the process of luteinization normally happens after ovulation, in which increasing LH levels cause a fall in FSH levels and a rise in progesterone levels. However, if luteinization occurs prior to the oocyte leaving the ovary, the chance of conception is reduced.
Dr. Wu says these findings show that is it not the aging eggs themselves that are responsible for lower IVF success among older women, but the aging of the eggs’ environment that is to blame. Tighter hormonal control of the womb’s environment, then, may be a key factor in increasing IVF success rates in women over 40 years of age.
Whiteman, H. (2015, August 12). “New IVF approach could boost success rates for older women.” Medical News Today. Retrieved from