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A Randomized Trial of Pessary and Progesterone for Preterm Prevention in Twin Gestation with a Short Cervix

IRB#: UNC: 15-0601, Wake: 761390

The purpose of this study is to find out whether a pessary or vaginal progesterone lowers the risk of babies being born preterm to women with a short cervix. A pessary is a round, soft silicone device that goes around the cervix. Progesterone is a hormone naturally produced by the placenta.

All women with twin pregnancies will be asked to be screened for this study.

If you consent to screening for this study, your cervix will be measured by a vaginal ultrasound. This is done as a part of routine care with many twin pregnancies at the time of the normal anatomy scan between 18-20 weeks.

If the length of your cervix measures less than 30 mm (about 1 inch), a member of the research staff may contact you to talk about taking part in a study in which you will be randomized (like choosing one of three numbers out of a hat) into one of three treatment groups: 1) the pessary group will have a pessary placed around the cervix, 2) the progesterone group will be given vaginal progesterone capsules, and 3) the placebo group will be given vaginal placebo capsules (the capsules look like the progesterone capsules but contain no medicine). If the length of your cervix measures between 30 mm and 35 mm (about 1 to 1½ inches), a member of the research staff may ask you to have another vaginal ultrasound within one to four weeks to see if your cervix measures less than 30 mm at that time. You and your doctor will be informed of the results of your screening ultrasound examination.

You may be qualified if the following applies to you:

  • Your cervical length on transvaginal examination is less than 30 millimeters.
  • You are pregnant with twins
  • You are less than 24 weeks pregnant.

You may not be able to participate if:

  • Your cervix is dilated 2 centimeters or more
  • You have a monoamniotic twin pregnancy (Where there is only one amniotic sac around both babies)
  • You have been diagnosed with twin to twin transfusion syndrome
  • You are diagnosed with fetal growth restriction as defined by a EFW of less than the 5th percentile
  • One or both of your babies have died or has birth defects
  • You have Placenta Previa
  • You have active vaginal bleeding
  • You have ruptured membranes
  • You are having more than 6 contractions per hour prior to enrollment in the study
  • You have any maternal uterine malformations or maternal medical illnesses, including active vaginal or cervical infections
  • You plan to have a cerclage
  • You plan to deliver you twins before 35 weeks
  • You plan to use progesterone therapy of any type or form after 14 weeks, 6 days of pregnancy
  • You have an allergy to progesterone or silicone
  • You have an allergy to peanuts
  • Participation in another interventional study that influences gestational age at delivery or neonatal morbidity or mortality
  • You plan to deliver at a non-network site unless study visits can be made as scheduled and delivery information can be obtained.

If you’re not sure if you qualify please contact us so we can help guide you.

Dates of Study

Projected start date of July 2015 until 630 women have been randomized nationally.

Contact Information

This study is funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). Conducted by the NICHD Maternal-Fetal Medicine Units (MFMU). All biostatistical information is the responsibility of the Biostatistical Coordinating Center (BCC) at George Washington University.

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The Maternal Fetal Medicine Network is funded by the

NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development