In women with a short cervix, treatment with progesterone reduces the rate of spontaneous early preterm delivery, 
that was a statement described in the article in August 2007, one of NEJM journals. It is unknown whether progesterone reduces this risk in such women. In previous study, it stated that the giving of progesterone in women who previously delivered prematurely reduces the risk of recurrent premature delivery. But a woman who have short cervix are at greatly increased risk for spontaneous early preterm delivery, and it remains unclear whether progesteron can reduce this risk in such women.
The researchers measured cervical length by transvaginal ultrasonography at a median of 22 weeks of gestation in 24,620 pregnant women seen for routine prenatal care. The primary outcome was spontaneous delivery before 34 weeks.
Eduardo B. Fonseca, M.D.,and colleagues found that giving progesteron in midgestation to women who previously had a preterm birth has been shown to halve the rate of recurrence. Then they designed a multicenter, randomized trial to evaluate the effect of vaginal progesterone on the incidence of spontaneous early preterm delivery in asymptomatic women found at routine mid-trimester screening to have a short cervix. They used 200 mg of progesterone, in contrast to the 100-mg dose used in a randomized trial of women with a history of preterm birth.
And the results said that in women with a short cervix, the daily vaginal administration of 200 mg of progesterone from 24 to 34 weeks of gestation significantly reduces the rate of spontaneous preterm delivery.
Read Progesteron’s Effect in Reducing Preterm Delivery from its original tittle in free downloadable PDF Filetype (source: nejm.org).
