The Risk of Advanced Maternal Age: Causes and Overview

As an important factor of chromosome abnormality in offspring, elderly pregnant women have attracted more and more attention. Studies have confirmed that the offspring of older pregnant women, whether conceived naturally or through assisted reproductive technology, are more likely to develop chromosome abnormalities than younger pregnant women, and the reasons have not been fully explained. The spindle assembly checkpoint monitors the correct connection between all mobile axes and the spindle. The bipolar spindle is the key to cell division to guide the correct separation of chromosomes and is the main gatekeeper to prevent the development of oocytes carrying DNA damage. Older pregnant women lead to the error of sister chromatid separation and the decrease of chromosome cohesion. The integrity of telomeres also affects the folding of DNA and the ability of cells to replicate. In addition, more oxidative stress makes the ovaries of older pregnant women unable to support fertilization and embryonic development. With the oxygen free radicals increase, the pathway of ovarian cell apoptosis and mitochondrial repair were changed. Therefore, the analysis of the causes of fetal chromosome abnormalities in elderly pregnant women is helpful to improve the understanding of the particularity of pregnancy in elderly pregnant women, so as to reduce the birth of defective babies and improve the birth quality.