**2. Prevalence**

Nowadays, the prevalence of induction of labor in the field of obstetrics is increasing. According to a WHO report, up to 25% of all term deliveries in developed countries were following labor induction for different reasons. In the United States and England, labor induction accounts for 29% [4] of deliveries, while 12.1% and 4.4% of deliveries are induced in Asian and African regions, respectively [5].

However, even if induction of labor is practiced widely in the field of obstetrics, it has variations from setting to setting, with studies showing that facilities in developing countries tend to have lower rates of induction of labor than in developed countries. One systematic study shows that the average induction rate was 4.4% in African, 12.1% in Asian, and 11.4% in Latin American countries, which has a huge difference from that in developed countries [5, 6].

### **3. Indications and contraindications of induction of labor**

The decision to induce labor was never an easy task and requires a complex clinical judgment. It usually constitutes a choice between three options, allowing the pregnancy to continue, inducing labor, or performing cesarean section, and needs the consideration of a number of factors [2]. Some of the factors are the condition of the baby, gestational age and the level of certainty about the baby's age (rarely, preterm induction may have to be done.), history of previous cesarean section, the preference of the mother, and the likelihood that induction of labor will be efficient and vaginal delivery could be achieved, which in turn is dependent on the state of the uterine cervix and birth canal [3, 7].

Taking the above conditions in to consideration, there are various indications that might require labor induction. These factors could be maternal or fetal and sometimes both.

#### **3.1 Maternal indications**

Maternal conditions that necessitate labor induction could be medical conditions or discomforts that have been caused or aggravated by pregnancy [8, 9]. These indications include:

• Preeclampsia/eclampsia
