Case 1 Continued
MC initiated treatment with daily vaginal progesterone at 18 weeks’ gestation and returned for ultrasound cervical length examination weekly instead of every other week. At 20 weeks’ gestation, cervical length was 2.0 cm; the following week it was 1.4 cm. What would you recommend at this point?
When to consider cerclage
If cervical shortening progresses to about 1.5 cm while a woman is being treated with vaginal progesterone, cerclage may be considered. The benefit of cerclage in patients with prior PTD and a short cervix was highlighted in a 2018 Cochrane Review.20 In this stepwise management approach to a short cervix, waiting for a cervix to be less than 1.5 cm may be unadvisable. Under conditions of a very short cervix that is frequently dilated with exposure of fetal membranes, ascending subclinical intra-amniotic infection may already be present, reducing the efficacy of any preventive measures. Preferential consideration for cerclage from the start over initial vaginal progesterone also may be appropriate when there is a history of 2 spontaneous PTDs or mid-trimester losses, a history of a successful cerclage, or with a very short cervix (< 1.0 cm) at the initial evaluation. As for the latter, a 2018 individual patient data meta-analysis of vaginal progesterone found no benefit when the cervix was less than 1.0 cm.13
Progesterone plus cerclage likely to add benefit
The results of an adjusted indirect comparison meta-analysis suggest that both interventions—vaginal progesterone and cerclage—are equally effective.21 Assuming that there is no clinically meaningful difference in benefit associated with these 2 treatments, the next logical question is whether combining the 2 therapies provides any added benefit; limited observational data seem to suggest that it does. In a retrospective cohort of 86 consecutive singleton pregnancies among women who underwent ultrasound-indicated cerclage, those who used vaginal progesterone after cerclage (n = 45) had a lower rate of PTD.22 Also, a small (66 cases) case-control study demonstrated the benefit of administration of vaginal progesterone as a rescue intervention in women with cerclage and progressive cervical shortening despite cerclage.23
Case 2 Woman experiences adverse effects from vaginal progesterone
MS is a 25-year-old G2P0101 who was started on vaginal progesterone as prophylaxis for recurrent PTD. She is now at 20 weeks’ gestation, with a stable remnant cervical length of 2.0 cm. She is reporting an increasing vaginal burning sensation and vaginal discharge caused by the nightly vaginal progesterone applications, to the point that she is unwilling to continue the treatment. She asks if any alternatives to vaginal progesterone are available to decrease her risk of PTD.
Continue to: Is oral progesterone an option?...