Being in your thirties is considered advanced maternal age.

Generally speaking, the age of 35 is considered advanced maternal age. The detailed analysis is as follows:

In medicine, an advanced maternal age pregnancy typically refers to a pregnant woman who is over 35 years old. This is because, as women age, both the quantity and quality of their eggs gradually decline, thereby increasing certain risks during pregnancy and childbirth. With the development of modern society, an increasing number of women are choosing to marry and have children later in life, leading to a rising average age at conception. However, the risks associated with advanced maternal age also increase accordingly. Both the number and quality of a woman's eggs decrease with age, making conception more difficult. Therefore, older mothers are more likely to face infertility or subfertility issues. Advanced maternal age women may also be at higher risk of spontaneous miscarriage in early pregnancy, which is related to declining egg quality and hormonal levels. Increasing maternal age raises the risk of fetal chromosomal abnormalities. For example, the incidence of Down syndrome is closely related to maternal age, with a significantly increased risk for pregnant women aged 35 and above. Older mothers are also more prone to develop pregnancy-related complications such as gestational hypertension and gestational diabetes. Advanced age may also increase the risk of delivery complications, such as prolonged labor and placental abruption.

Although age is an important factor, it is not the sole determinant of risks associated with advanced maternal age. Individual overall health status, lifestyle, and family history of genetic disorders can also influence these risks.