What effects does inflammation/infection have on the risk of spontaneous preterm birth?

• A. Increases protein levels in the amniotic fluid
• B. Degrades membranes and induces inflammatory cytokines
• C. Reduces uterine contractility
• D. Increases placental thickness

Answer: (B)

Inflammation and infection during pregnancy play a significant role in the risk of spontaneous preterm birth, primarily through the degradation of membranes and the induction of inflammatory cytokines. When an infection occurs, the body's immune response initiates inflammation, which can affect various structures within the reproductive system.

The degradation of membranes refers to the weakening of the amniotic sac, which is critical for maintaining the environment for the developing fetus. This degeneration can trigger a chain of events leading to preterm labor. In addition, the presence of inflammatory cytokines released during an infection can stimulate uterine contractions and may contribute to cervical changes, both of which are critical factors in the onset of labor.

Therefore, the process by which inflammation and infection induce these changes forms a clear pathway to increased spontaneous preterm birth risk, making this answer the most accurate in reflecting the mechanisms involved. Other options touch on aspects that are less directly related to the mechanisms leading to preterm birth in the context of infection and inflammation.