Abstract

Preterm delivery is traditionally known as birth that occurs after 20 weeks and before completing 37 weeks of gestation; however, this definition is being reevaluated. In developed countries, preterm delivery is the primary cause of children mortality and it significantly increases their morbidity. It is fundamental to determine its predisposing factors, in order to detect mothers at risk and consequently, avoid this adverse outcome.

Some of the known risk factors for preterm delivery are: short cervical length, demographic characteristics, history of cervical surgery, previous preterm delivery, vaginal bleeding during the first trimester, obesity, infections, smoking, low preconceptional weight, substance abuse, and short interpregnancy interval.

On the other hand, some effective prevention measures may include: better prenatal control, antibiotic treatment for certain genital infections, in patients with premature rupture of membranes, and asymptomatic bacteriuria; supplementation of progesterone in patients with or without history of previous preterm delivery, but with very short cervical length before the 24th week of gestation, use of cervical cerclaje in women with history of preterm delivery before 34 weeks and cervical length less than 25 mm at 24 weeks of gestation, use of pessary in asymptomatic women without history of preterm delivery with incidental diagnosis of short cervix at 18-22 weeks of gestation, zinc supplementation in women with low income and malnutrition, and finally, interpregnancy interval longer than 12 months.

Key words: Preterm delivery - risk factors - prevention - pregnancy - progesterone - cerclaje