What factors contribute to the likelihood of preterm birth associated with a bicornuate uterus?

A bicornuate uterus is a congenital anomaly resulting from the incomplete fusion of the Müllerian ducts during fetal development. This structural abnormality can lead to an increased likelihood of preterm birth due to several factors, primarily related to its shape and the limited space it provides for a growing fetus.

The option highlighting limited uterus fusion is significant because a bicornuate uterus has a divided cavity, which can restrict fetal growth and lead to complications such as abnormal placentation, cervical insufficiency, and increased uterine contractility. These factors can directly contribute to preterm labor, as the uterus may not be able to accommodate the developing fetus adequately, thus leading to an earlier delivery.

Furthermore, the anatomy of a bicornuate uterus can lead to increased risks of complications like preterm rupture of membranes and preterm labor, which are not typically associated with a normally structured uterus. Other options, while relevant to overall reproductive health, do not directly influence the structural limitations imposed by a bicornuate uterus on pregnancy outcomes. Therefore, understanding the anatomical and physiological implications of a bicornuate uterus is essential in assessing the risks of preterm birth associated with this condition.