The effect of coadministration of oral propranolol to oxytocin on induction of labor.

Study hypothesis:

Oral propranolol when used with oxytocin during the process of labor may reduce labor interval and decrease the rate of cesarean delivery.

Study population:

The patients will be recruited from the women attending obstetrics reception room, in Ain Shams University Maternity Hospital.

Intervention:

After taking informed consent, all patients recruited in the study will undergo complete clinical examination and detailed medical history will be obtained along with necessary laboratory investigations and ultrasound. Each patient will have a case record form in which the following data will be recorded:

1. History: personal (age, duration of marriage), present illness (any current medical or surgical diseases and any current medication), obstetric history (including parity, gestational age, obstetric complications) and past medical history(especially cardiac problems).

2. Clinical examination:

   1. General examination: assessment of vital data, cardiac and chest auscultation to exclude contraindications for drug administration.
   2. Abdominal examination: assessment of fundal level and contractions if present.
   3. Pelvic examination: assessment of Bishop score, membrane status and fetal presentation.

3. Investigations:

   1. Routine investigations will be done e.g., Full blood count, CRP titre.
   2. Pelvi-abdominal U/S (confirm fetal life, placental location, fetus parameters, amniotic fluid index, expected fetal weight).

Steps:

1. Informed consent will be obtained from parents or guardians of patients who are invited to participate in the research after explanation of benefits and risks of this trial.
2. A capsule containing 20 mg propranolol to the first group (propranolol plus oxytocin) and a similar capsule as a placebo to the second group (oxytocin plus placebo) are administrated orally before beginning induction. Oral capsules are repeated after 8 h, if three forceful contractions are not obtained during 10 min.
3. Induction will be initiated with a dose of 2 mIu/min and increased by 2 mIu/min every 15 min until three forceful contractions be obtained for 10 min, or to a maximum dose of 30 mIu/min. Then, continue at this rate for 8 h. If patients entered the active phase of labor (cervical dilatation = 3-4 cm), induction continue until delivery.
4. Amniotomy is performed when cervical dilation reached 5 cm, if the membrane has not been ruptured spontaneously.
5. The partogram will be used to monitor the fetal heart rate, membrane status, cervical dilation and effacement, station of the fetus, uterine contractions, maternal pulse, maternal blood pressure, maternal temperature.
6. If there is no response to induction on the second day, a cesarean section will be performed.
7. The participants are followed up until delivery.

Safety Considerations:

If the parturient has hyperstimulation of contractions (in a situation with more than 5 contractions/10 min, duration of contraction > 90 sec, interval of contraction less than 2 min, or fetal distress), the induction will be stopped, and the parturient is kept in left lateral position and given oxygen, and intravenous dextrose.

Inclusion Criteria:

1. Gestational age above 37 weeks.
2. Fetal life positive on ultrasound.
3. Bishop score > 5.
4. Primiparous women.

Exclusion Criteria:

1. history of uterine surgery
2. polyhydramnios
3. contraindications to β-adrenergic agents, such as systolic blood pressure less than 100 mmHg or pulse rate less than 60/min and more than 120/min
4. history of any known cardiac disease
5. mother's pulmonary or metabolic disorders
6. fetal distress
7. estimated weight of the fetus more than 4 kg by ultrasound of cephalic presentation