What risk factor is most associated with prematurity?

Advanced maternal age is most associated with prematurity due to several physiological and contextual factors. As mothers age, particularly those over the age of 35, they may experience a higher likelihood of complications during pregnancy. These complications can include increased rates of chronic health conditions such as hypertension or diabetes, which can lead to preterm labor. Additionally, older mothers may encounter challenges related to fertility treatments or may have higher rates of multiple gestations, which are also associated with an increased risk of preterm birth.

In contrast, single gestation typically has a lower association with prematurity compared to multiple gestations, as carrying more than one fetus significantly raises the risk of early delivery. High socioeconomic status (SES) usually correlates with better access to healthcare, nutrition, and prenatal care, thus reducing the risk of prematurity. Finally, having prior full-term births can indicate a history of successful pregnancies, which may suggest that a woman has a lower risk of prematurity in subsequent pregnancies. Thus, advanced maternal age emerges as a prominent factor linked to the likelihood of premature birth.