Please select the eligibility criteria that correspond to the clinical trial below.
Title: Comparative Study Between Nifedipine and Ritodrine as Maintenance Tocolytic Therapy in Preterm Labor: A Randomized Controlled Trial
Brief Summary: A randomized controlled double blinded study included 200 women with preterm contractions. After successful arrest of contractions women were randomized into 2 equal groups: GI women received nifedipine 20 mg tablets twice daily and GII women received Ritodrine 5 mg tablets every 6 hours. The primary outcome was gestational age at delivery and the secondary outcomes include episodes of recurrent preterm labor, mode of delivery, maternal side effects and neonatal outcome


Options:
A: Inclusion Criteria:

* pregnancy week 24-33
* Singleton pregnancy
* After successful treatment to stop PTL

Exclusion Criteria:

* Contraindications for Nifedipine extended release treatment.
B: Inclusion Criteria:

* Women included in the study were diagnosed as preterm labor defined according to American Academy of Pediatrics and the American College of Obstetricians and Gynecologists (2012) with regular contractions before 37 weeks that are associated with cervical change .

Regular uterine contractions means at least 4 in 20 minutes or 8 in 60 minutes) and cervical changes are either cervical dilation more than 1 cm, and/or cervical effacement ≥ 80%. Threatened preterm labour was defined as contractions without any appreciable cervical changes. Women included were between 18 and 40 years old at gestational age between 28 and 34 weeks

Exclusion Criteria:

* Women with failed tocolytic treatment to stop uterine contractions,
* those with established preterm labor (cervical dilatation ≥ 4 cm),
* multifetal pregnancy
* fetal anomalies
* those with contraindication of continuation of pregnancy (antepartum hemorrhage, premature rupture of membranes, evidence of intrauterine infections or non reassuring fetal heart rate tracing)
C: Inclusion Criteria:

* . Gestational age between 24-37weeks

  * Symptoms such as low backache , cramping ,pelvic pressure, excessive vaginal discharge and vaginal spotting .
  * Regular uterine contractions at least of 30 seconds duration at a rate of more than 4/30 minutes
  * Cervical changes dilatation less than 3cm,effacement lessthan50%.
  * Intact membranes.

Exclusion criteria

* Active vaginal bleeding and placental abruption.
* Chorioamnionitis and intrauterine infection
* Fetal conditions : fetal death or distress, lethal congenital or chromosomal abnormalities and intra uterine growth restriction
* Maternal conditions indicate that pregnancy shouldn't be continued: eclampsia , severe preeclampsia and cardiac diseases
* Drug specific contraindications(contraindication of tocolysis)
D: Inclusion Criteria:

* Singe fetus
* Gestational age between 24+0/7 and 31+6/7
* At least one uterine contraction in ten minutes for at least 20 minutes upon tocography admission
* Cervical parameters: 1 cm dilation or more or 80% cervical effacement or cervical length 20mm or less

Exclusion Criteria:

* Rupture of membranes
* Vaginal bleeding
* Cervical dilation ≥5cm
* Known fetal malformations
* Fetal heart rate abnormalities
* Suspected placental abruption of adherent placental syndrome
* Known sensitivity to one of the drugs used in the study (Indometacin and nifedipine)
* Maternal hypotension and known aortic or mitral stenosis
* Presence of cervical cerclage
* Previous administration of tocolytic drugs in current pregnancy

Answer: B