Vilma L Johnsson1, Nina G Pedersen1, Katharina Worda2, Elisabeth Krampl-Bettelheim2, Lillian Skibsted3,4, Stefan Hinterberger5, Isolde Strobl6, Maria E Bowman7, Roger Smith7, Ann Tabor1,4, Line Rode1,8. 1. Center of Fetal Medicine and Pregnancy, Department of Obstetrics, Copenhagen University Hospital Rigshospitalet, , Copenhagen, Denmark. 2. Department of Obstetrics and Gynecology, Medical University of Vienna, Vienna, Austria. 3. Department of Obstetrics and Gynecology, University Hospital Roskilde, Roskilde, Denmark. 4. Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark. 5. Department of Obstetrics and Gynecology, General Hospital of Klagenfurt, Klagenfurt, Austria. 6. Department of Obstetrics and Gynecology, Medical University of Innsbruck, Innsbruck, Austria. 7. Mothers and Babies Research Center/Hunter Medical Research Institute, John Hunter Hospital, Faculty of Health/School of Medicine and Public Health, University of Newcastle, Newcastle, NSW, Australia. 8. Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Denmark.
Abstract
INTRODUCTION: The aim of this study was to examine the association between plasma hormone concentrations, cervical length, and preterm delivery in twin pregnancies, including the effect of progesterone treatment. MATERIAL AND METHODS: This study included 191 women pregnant with twins from a randomizedplacebo-controlled trial. A baseline blood sample was collected at 18-24 weeks before treatment with vaginal progesterone (n = 95) or placebo pessaries (n = 96), and 167 (87.4%) women had a second sample collected after 4-8 weeks of treatment. At baseline, 155 (81.2%) women had their cervical length measured. Progesterone, estradiol, and unconjugated estriol concentration was measured, and the association between hormone concentrations, cervical length, and gestational age at delivery was examined. Hormone concentrations were compared in the placebo and progesterone group. Statistical analysis included Spearman's rho, Mann-Whitney U test, Cuzick's test for trends, and linear regression analyses. RESULTS: A short cervical length was associated with preterm delivery. Cervical length and hormone concentrations were not associated (Spearman's rho; progesterone -.05, estradiol .04, estriol .08). Decreasing gestational age at delivery was associated with higher progesterone and estradiol concentrations at baseline (P trend; progesterone 0.04, estradiol 0.02) but not in the second sample or in the weekly change between samples. Progesterone treatment did not increase the progesterone concentration. CONCLUSIONS:Plasma concentrations of progesterone, estradiol, and unconjugated estriol at 18-24 weeks are not associated with cervical length or preterm delivery in twin pregnancies. Vaginal progesterone treatment does not increase the circulating progesterone concentration in twin pregnancies. Cervical length, but not hormone concentration, is predictive of preterm delivery in twin gestations.
RCT Entities:
INTRODUCTION: The aim of this study was to examine the association between plasma hormone concentrations, cervical length, and preterm delivery in twin pregnancies, including the effect of progesterone treatment. MATERIAL AND METHODS: This study included 191 women pregnant with twins from a randomized placebo-controlled trial. A baseline blood sample was collected at 18-24 weeks before treatment with vaginal progesterone (n = 95) or placebo pessaries (n = 96), and 167 (87.4%) women had a second sample collected after 4-8 weeks of treatment. At baseline, 155 (81.2%) women had their cervical length measured. Progesterone, estradiol, and unconjugated estriol concentration was measured, and the association between hormone concentrations, cervical length, and gestational age at delivery was examined. Hormone concentrations were compared in the placebo and progesterone group. Statistical analysis included Spearman's rho, Mann-Whitney U test, Cuzick's test for trends, and linear regression analyses. RESULTS: A short cervical length was associated with preterm delivery. Cervical length and hormone concentrations were not associated (Spearman's rho; progesterone -.05, estradiol .04, estriol .08). Decreasing gestational age at delivery was associated with higher progesterone and estradiol concentrations at baseline (P trend; progesterone 0.04, estradiol 0.02) but not in the second sample or in the weekly change between samples. Progesterone treatment did not increase the progesterone concentration. CONCLUSIONS: Plasma concentrations of progesterone, estradiol, and unconjugated estriol at 18-24 weeks are not associated with cervical length or preterm delivery in twin pregnancies. Vaginal progesterone treatment does not increase the circulating progesterone concentration in twin pregnancies. Cervical length, but not hormone concentration, is predictive of preterm delivery in twin gestations.