A paper published in the journal Nature pointed out that uterine age affects the success rate of embryo transfer and conception in mice. Previous research has focused on how egg cell defects can cause age-related pregnancy complications, but new findings indicate that the maternal environment is also an important factor in pregnancy complications. As we all know, the aging of pregnant women is an important factor that increases the risk of reproduction. The aging of egg cells can lead to abnormal chromosomes in the embryo, leading to premature birth. Myriam Hemberger and colleagues studied mice and suggested possible causes of pregnancy complications (such as miscarriage and perinatal death) during the second trimester. They observed that the health and survival rate of the fetus decreased as the mother ages in the mice. Health problems that occur include developmental delays and heart defects. These are related to the placental defect in the uterus, which provides nutrition for the embryo.
The authors show that these problems can be solved by transferring embryos from older mothers to younger recipients. Experiments have shown that the ability of the uterus to nourish the placenta and embryos decreases with age. Uterine aging is related to the decrease in the number of immune cells in the decidua, which is a uterine structure that, together with the placenta, supports the growth and development of the embryo. The authors also found that with age, there are fewer and fewer cells in the uterus that respond to hormones that stimulate the formation of decidua. These results indicate that the age of the mouse's mother affects the survival of the embryo. This is attributed to the age of the uterus and the age of the egg cells, and provides more information to support embryo health and survival. Please note that this study is limited to mice, and there is currently no evidence that this mechanism exists in humans.