Grobman (2012) n = 657; singletons only; nulliparous <30nmm 17-0HP-C, 250 mg 1M Delivery <37 weeks: only; 14 centers across US weekly 25% vs 24%, p = NS
Determined sonographically.
17-0HP-C = 17-hydroxyprogesterone caproate; 1M = intramuscularly; NS = nonsignificant; PTB = preterm birth; UK = United Kingdom; US = United States.
colleagues (2007) randomly assigned 250 women with short cervices measuringr:;15 mm identified during routine prenatal care. Women were given nightly 200-mg micronized progesterone vaginal capsules or placebo from 24 to 34 weeks' gestation. Spontaneous delivery <34 weeks was significantly reduced by progesterone therapy. Importantly, this trial included not only nulliparas but also those with twins or prior pre term birth.
In the second trial, Hassan and coworkers (2011) randomly assigned 465 women with a short cervix-IO to 20 mm-to vaginal progesterone gel, 90 mg daily, or placebo. his trial also included nulliparas and women with prior preterm births.
From these studies, the FDA rejected progesterone gel for use because the results did not meet the level of statistical significance required to show eicacy in the subjects recruited in the United States. According to Likis and colleagues (2012), the heterogeneity of these first two studies that included women with varied indications for progestogen treatment, combined with the fact that outcomes were not reported by risk factors such as nulliparity, made it impossible to interpret the eicacy of progesterone for speciic indications.
The third study randomly assigned administration of 17 -0 HP -C intramuscular injection or placebo between 16 and 223/7 weeks to nulliparas with a singleton gestation and a cervical length < 30 mm detected sonographically (Table 42-8) (Grobman, 2012). Treatment with 17-0HP-C given weekly did not reduce the frequency of preterm birth before 37 weeks. Regardless of cervical length, 17-0 HP -C was inefective.
hus, vaginal progesterone, but not 17 -OHP-C, appears to benefit women with a sonographically measured short cervix. Romero and Stanczyk (2013) provided a review to explain the conlicting evidence and argued that naturally occurring progesterone, which is used in the vaginal preparations, is not the same as synthetic 17-0HP-C. Likewise, Furcron and coworkers (2015) found that 17-0 HP -C did not have local antiinflammatory efects at the maternal-fetal interface or cervix. Further, 17 -OHP-C did not protect against endotoxin-induced preterm birth.
From all these studies, the merican College of Obstetricians and Gynecologists (2016c) concluded that universal cervical length screening in women without a prior preterm birth is not mandatory. However, this screening strategy could be considered in the context of treatment with vaginal progesterone.
The OPPTIMUM Study his study of 1228 high-risk women with singleton pregnancies is the largest to date for vaginal progesterone prophylaxis (N orman, 2016). his randomized trial of vaginal progesterone, 200 mg daily from 22-24 weeks to 34 weeks of gestation, was termed the OPPTIMUM study-dQes Erogesterone Erophyxis Io prevent preterm labor prove High-risk women were defined as those with a prior spontaneous birth :;34 weeks or with a cervical length :;25 mm or a positive FN test result combined with other clinical risk factors for preterm birth.