What causes preterm labor and birth?
Despite serious efforts to reduce preterm birth, there is little good news. Factors that start a normal, term labor are poorly understood, and preterm labor is more perplexing. Researchers have tried to identify the causes of preterm labor and birth, the women who are at risk, and ways to prevent or treat preterm labor. Very few clear answers have emerged. Most often, the cause of preterm labor is unknown. Sometimes malformations of the uterus or cervix are associated with early delivery. Often these are unknown to the woman prior to becoming pregnant. Even if known, how much a uterine fibroid or unusually shaped uterus will affect the pregnancy is often difficult to predict. One cause of preterm labor is premature (before labor begins), preterm (before full term) rupture of membranes. It is not known why the fetal membranes rupture too early in some pregnancies. When the fluid around the baby leaks out, the baby and mother are exposed to infection. Labor usually occurs within a few da
