Essay: Induction of labour

The rate of induction of labor is different worldwide. It varies between different countries and even between different regions of the same country. The WHO Global survey on maternal and perinatal health in 24 countries showed that 9.6% of all, deliveries involved induction of labor (9).
Overall, the induction of labour is higher in developed countries than in developing countries. In the United States of America and United Kingdom 20% of all deliveries are due to induction of labor (10).The rates of induction are on rise in developed countries which is attributed mainly to patient and physician factor (11) . According to the WHO Global secondary survey by Fawole and colleagues induction of labor in developing countries is low 4.4% in Africa& 12.1% in Asia (12)
In South Africa in regional hospital in Gauteng the rate of induction was 9.6 % (13). Induction of labour is indicated when the benefits to mother or fetus are more than the risk of continuing the pregnancy. Induction of labor improves maternal and neonatal outcomes and is directly related to millennium development goals . The main aim of induction of labor is successful vaginal delivery as the morbidity associated with operative delivery is reduced . Induction of labor improves fetal outcome which is found to be increased beyond 41 weeks of gestation age (14).
To decrease the caesarean section is an important step in low resource settings as the risks with caesarean delivery are more (12). Induction of labor lowers the caesarean deliveries, In the hospitals where induction of labor is more practiced there are less numbers of caesarean deliveries (15)
In a study by Ibrahim in Nigeria the rate of induction of labor was found to be 6.5%, majority of women delivered within 12 hours after induction .Reduction in time from induction to delivery is of advantage to the pregnant mothers and their family as the duration of labor decreases, it helps in reducing the congestion in the labor wards.(16)
In another study in Nigeria most of the parturient (75.9%) had vaginal delivery, while 24.1% had emergency caesarean section .(17)
In a study at Kinshasa at democratic republic of Congo, the outcomes after induction of labor included SVD in 66.9% of women and caesarean section in 29.6% (18) .
Maternal and neonatal outcome
According to a Secondary Analysis of the WHO Global Survey on Maternal and Neonatal Health, the main maternal outcomes were delivery by caesarean section after induction of labour ,maternal death, perennial laceration ,blood transfusion, postpartum hospital stay for 7 days. The neonatal outcomes were APGAR score less than 7 at 5 minutes ,low birth weight, fresh still birth ,admission to neonatal wards and neonatal death occurring before the discharge of the patients (19). In a study done in Canada, at University of Toronto for the effects of induction of labor on still births ,it was observed that induction of labor was associated with reduction in stillbirth among postdate women (20).
According to a study done in South Africa 59.8% of women had spontaneous vaginal delivery and 40.2 % had caesarean section. The women also had post-partum hemorrhage, puerperal sepsis and 6.8% of babies were admitted to neonatal wards out of which 2.0% were premature, 1.85% had hypoxic ischemic encephalopathy and there was one early neonatal death(13).
Indications for induction of labour
The most common reason for induction of labor worldwide is hypertensive disorders of pregnancy (21)
Postdate pregnancy as it carries risk to the neonate due to the ageing of the placenta leading to placental insufficiency with advancing gestation .Postdate pregnancy is also associated with increased birth trauma and meconium aspiration. Induction also helps in reducing, perinatal deaths and still births which are associated with postdate pregnancy (22)
Postdate pregnancy and hypertensive disorders of pregnancy were the common indications in the study done in Sokoto, where the proportion of postdate pregnancy was 45.8%, Premature rupture of membranes 31.9%, Intra uterine fetal death 12.4%, (23). The NICE guidelines recommend induction of labor after 34 weeks in Premature rupture of membranes as there is increased risk of maternal and fetal infections due to rupture of membranes (1).
In a study done by Ibrahim et al in Nigeria the proportion of postdate pregnancy was 51.7%, premature rupture of membranes 31.7% and hypertension in pregnancy 10.0%(16) The main indications in a study at Kinshasa were hypertensive disorder 54.1%, PROM 29.5%, postdate 14.6%(18) .In a study done at Kenyatta National Hospital by Marian the most common indication of labor was postdates 133(50.0%) followed by hypertensive disorders 42(16%), followed by premature rupture of membrane 22 (8.4%) (24).
According to ACOG the maternal and neonatal indication of induction includes conditions such as Abruptio placentae,postdate pregnancy PROM .Maternal medical conditions eg diabetes mellitus , renal disease, ,chronic pulmonary disease,chronic hypertension ,antiphispholipid syndrome. Fetal indications include chorioamnionitis, intrauterine fetal death,oligohydramnios ,isoimmunization ,severe fetal growth restriction(10).
According to the study done in Pakistan18.1% had failed induction of labor and it was more common among nulliparous women who had poor Bishops score(25) .The indications for caesarean section in the study done in South Africa were Cephalopelvic disproportion 14.9% and failed IOL 12.9 %(13). Ceplhalopelvic disproportion was the most common indication for operative delivery in 5 (8.3%) women undergoing induction of labor in the study done in Nigeria(16) .
Failed induction of labor means that women do not enter active labor. Failed induction is defined as failure to establish labor after one cycle of treatment, which includes the insertion of two vaginal PGE2 tablets 10 mg at 12 -hourly intervals, or one PGE2 controlled released pessary (10 mg) over 24 hours (26,27). The subsequent management of failed induction needs a further attempt to induce labor or a caesarean section (1).
There is need for a study which will help us to know the maternal and neonatal outcome in induction of labor in our hospital. These studies have been done in different parts of the world, where the induction is high in developed countries and on the other hand it is low in developing countries.