Which of the following is a risk factor for preterm labor?

Multiple pregnancies, such as twins or triplets, are indeed a known risk factor for preterm labor. This is primarily due to the increased physical demands on the mother’s body, as well as the factors associated with carrying more than one fetus, such as uterine over-distension and hormonal changes that may trigger labor. The increased strain can lead to cervical changes and contractions that may result in preterm labor.

In contrast, carrying a single pregnancy, practicing yoga during pregnancy, and attending regular prenatal check-ups are less associated with preterm labor. Single pregnancies typically carry a lower risk of early labor compared to multiple pregnancies. Engaging in yoga, as part of a healthy pregnancy routine, can actually contribute positively to maternal well-being and may help in managing stress. Regular prenatal check-ups are essential for monitoring the health of both the mother and fetus and are linked to better pregnancy outcomes rather than increased risk of complications such as preterm labor.