Please select the eligibility criteria that correspond to the clinical trial below.
Title: Prevention of Preterm Birth With a Pessary in Singleton Gestations
Brief Summary: Preterm birth (PTB) is associated with over one million infant deaths annually worldwide. The incidence of PTB in the United States is 11.5% with more than 500,000 deliveries occurring at less than 37 weeks gestation annually. The rate of PTB in the United States increased to 12.8% in 2006, and remains high compared to almost all other developed countries, despite the introduction of many public health and medical interventions designed to delay PTB. Weekly treatment with 17-alpha hydroxyprogesterone caproate beginning at 16-20 weeks gestation has been shown to significantly reduce the risk of PTB and is currently recommended for women who experienced spontaneous PTB in a prior pregnancy. However, a strategy for the prevention of spontaneous PTBs in which therapeutic intervention is restricted to women with a previous PTB is likely to have a small effect on the overall rate of prematurity since only about 10% of spontaneous PTBs arise in women with such a history. A major reduction in rates of mortality and morbidity in premature babies will only be achieved with increased precision in the identification of women at risk of spontaneous PTB and through the development of an effective prevention for this complication. Transvaginal ultrasound measurement of cervical length is a reliable screening test for prediction of PTB. Although treatment with vaginal progesterone is effective in decreasing PTB in women with a short cervix, over 30% of women still experience premature delivery and many women find daily administration of progesterone to be challenging. Preliminary studies have suggested that use of an intravaginal pessary may be effective in preventing PTB. If effective this approach would be particularly appealing because of the wide availability of pessaries, ease of use, and low cost. Unfortunately, existing studies are inadequate to confirm effectiveness; a well designed, properly powered, prospective randomized trial is warranted prior to widespread implementation in clinical practice. We propose such a trial to study the effectiveness of the pessary in decreasing the incidence of PTB in an inner city Philadelphia population.


Options:
A: Inclusion Criteria:

1. Short cervical length equal or less than 20 mm
2. Singleton pregnant women between 18 -24 weeks with no prior history of preterm deliveries.
3. 18 years or older at the time of enrollment.
4. Consent to participate in the study

Exclusion Criteria:

1. Previous preterm delivery less than 37 weeks
2. Major fetal anomalies
3. Multiple pregnancy
4. Patient currently with cervical cerclage in-situ for the treatment of incompetence cervix.
5. Regular uterine contractions or significantly dilated cervical canal
6. Age less than 18 years
7. Decline to participate in the study
B: Inclusion Criteria:

* Pregnant women with short cervix (=\< 25 mm) identified by use of routine transvaginal ultrasonography at 19-22 weeks of gestation.
* Single pregnancy
* Women older than 18 year-old
* Women sign informed consent according GCP and local legislation
* Gestational age at randomization between 20+1 and 23+6 weeks.

Exclusion Criteria:

* Major fetal abnormalities
* Major uterine abnormalities
* Placenta praevia during current pregnancy
* Vaginal bleeding or ruptured membranes in the moment of randomization
* Cervical cerclage in situ
* History of cone biopsy
* Allergic to peanuts
* Contraindication for Progesterone usage.
* Active treatment with Progesterone at randomization.
* History of 3 or more premature labor.
* If in the investigator's opinion, there are findings on physical examination, abnormalities in the results of clinical analyzes or other medical factors, social or psycho-social that could negatively influence.
* Women unable to give the informed consent
C: Inclusion Criteria:

* Diagnosed to be pregnant at up to 24+0 weeks of gestation, with a cervical length measurement of ≤25 mm with a singleton pregnancy, or ≤38 mm in twins pregnancy.
* Does not meet with maternal/fetal/membrane/placental factors detailed in the exclusion criteria.
* Willingness to comply with the protocol for the duration of the study.
* Have signed an informed consent.

Exclusion Criteria:

* Fetal factors: major fetal abnormalities, death of one or both of the fetuses, twins- twin-to-twin transfusion syndrome, and severe growth retardation.
* Maternal factors: prophylactic cervical cerclage in situ, painful regular uterine contractions, active labor, active vaginal bleeding, maternal age under 18, uterine abnormalities (i.e. two cervices), and severe uterine prolapse.
* Membranes and placental factors: placenta previa, ruptured membranes.
D: Inclusion Criteria:

* 18-50 years of age
* Singleton pregnancy (limits the participants to female gender)
* Short cervical length (less than or equal to 25 mm) on second trimester ultrasound at 18-23 6/7 weeks gestation

Exclusion Criteria:

* Multiple gestation
* Prior spontaneous preterm birth 16-36 6/7 weeks
* Ruptured membranes
* Lethal fetal structural anomaly
* Fetal chromosomal abnormality
* Cerclage in place (or planned placement)
* Vaginal bleeding
* Suspicion of chorioamnionitis
* Ballooning of membranes outside the cervix into the vagina or CL = 0 mm on transvaginal ultrasound
* Painful regular uterine contractions
* Placenta previa

Answer: D