Effect of micronized progesterone on fetal-placental volume in first-trimester threatened abortion.

PURPOSE: To compare the effect of oral micronized progesterone (OMP) on the first-trimester fetal and placental volumes using three-dimensional ultrasonography and extended imaging virtual organ computer-aided analysis (XI VOCAL) method in threatened abortion.

METHODS: This randomized controlled trial enrolled women with threatened abortion and a singleton pregnancy from 6-8 6/7 weeks of gestation. A total of 60 women with threatened abortion were randomly assigned to one of two groups: OMP (400 mg/day) (n = 30) and control groups (n = 30). The XI VOCAL method was used for all volume measurements using three-dimensional ultrasonography. All patients were evaluated for fetal, amniotic, and placental volumes during the initial diagnosis and after 4 weeks.

RESULTS: After treatment, placental volume difference was significantly higher in the OMP group (336%, 67-1,077) than in the control group (141%, 29-900) (p = 0.007). The mean differences in gestational sac, amniotic sac, and embryonic volumes between the OMP and control groups were not statistically significant.

CONCLUSIONS: Hormonal support with OMP is associated with increased placental volume in first-trimester threatened abortion when compared with the control group. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:14-19, 2017.