Progesterone and preterm birth prevention: translating clinical trials data into clinical practice

Diagnosis/definition: The term “progestogens” includes both vaginal progesterone and 17-alpha-hydroxy-progesterone caproate (17P).

Management:
Screening/Work-up, and Prenatal care:

• There is insufficient evidence to recommend the use of progestogens in singleton gestations with no prior PTB and unknown CL.
• In women with singleton gestations, no prior PTB, and short CL ≤20mm at ≤24 weeks, vaginal progesterone, either 90-mg gel or 200-mg suppository, is associated with reduction in PTB and perinatal morbidity and mortality, and can be offered in these cases. (Figure)
• The issue of universal TVU CL screening of singleton gestations without prior PTB for the prevention of PTB remains an object of debate. CL screening in singleton gestations without prior PTB cannot yet be universally mandated. Nonetheless, implementation of such as creening strategy can be viewed as reasonable, and can be considered by individual practitioners. Given the impact on prenatal care and potential misuse of universal screening, stretching the criteria and management beyond those tested in RCTs should be prevented. Practitioners who decide to implement universal TVU CL screening should follow strict guidelines. Practitioners who choose to screen low-risk singleton gestations may consider offering vaginal progesterone, either 90-mg gel or 200-mg suppositories, for short TVU CL ≤20mm at ≤ 24 weeks.  
• In singleton gestations with prior PTB 20-36 6/7 weeks, 17-alpha-hydroxy-progesterone caproate 250 mg intramuscularly weekly, preferably starting at 16-20 weeks until 36 weeks, is recommended. In these women with prior PTB, if the transvaginal ultrasound CL shortens to <25mm at <24 weeks, cervical cerclage may be offered. (Figure)
• Progestogens have not been associated with prevention of PTB in women who have in the current pregnancy multiple gestations, preterm labor, or preterm premature rupture of membranes. There is insufficient evidence to recommend the use of progestogens in women with any of these risk factors, with or without a short CL. Some experts offer 17P to women with a prior SPTB and a current multiple gestation, but there are insufficient data to evaluate the risks and benefits of this intervention in this population.
• See table 3 for summary of these recommendations

Last Reaffirmed: Aug 1, 2014