Induction of labour is the stimulation of uterine contractions to achieve delivery before the onset of spontaneous labour after fetal viability, when the benefits of delivery outweigh the risks of continuing pregnancy. It is indicated when maternal or fetal complications may adversely affect outcomes, especially in postdated pregnancies. Various methods are available; in this study, one group received mifepristone and the other underwent induction with Foley’s catheter. Routine antenatal ultrasound for accurate confirmation of EDD has been shown to reduce unnecessary induction in postdated pregnancies by correcting gestational age ^1,2.

AIM AND OBJECTIVE

The objective of this study is to compare the safety and efficacy of mifepristone and Foley’s catheter for induction of labour in postdated pregnancies.

MATERIALS AND METHODS

This randomized controlled study was conducted in the Department of Obstetrics and Gynaecology at Coimbatore Medical College Hospital from January 2018 to December 2018, with a sample size of 200 postdated pregnant women. Inclusion criteria were singleton pregnancy with cephalic presentation, while women with hypertension, diabetes mellitus, multiple pregnancy, renal or heart disease complicating pregnancy, oligohydramnios, fetal growth restriction, macrosomia, or contracted pelvis were excluded. After obtaining informed written consent, detailed history and complete general, systemic, and obstetric examinations were performed. Routine investigations including complete blood count, urine analysis, blood grouping, HIV, HBsAg, VDRL, blood sugar, and obstetric ultrasound were carried out. The study population was randomized into two groups: one group received 200 mg oral mifepristone, and the other underwent induction with Foley’s catheter. Outcomes assessed after 24 hours included change in Bishop’s score, mode of delivery, induction–delivery interval, neonatal outcome, and incidence of Post Partum Hemorrhage (PPH). Based on the response, further augmentation with prostaglandin gel, amniotomy, or oxytocin was considered to ensure safe delivery.

RESULTS

A total of 200 women were included in the study, with 100 in the mifepristone group and 100 in the Foley’s catheter group. The mean age was comparable between groups (24.54 ± 3.94 years in the mifepristone group and 25.01 ± 3.21 years in the Foley’s group; p = 0.356), indicating no significant difference.

Regarding parity, in the mifepristone group, 63% were primigravida and 37% were multigravida, while in the Foley’s group, 72% were primigravida and 28% were multigravida. There was no statistically significant association between parity and type of induction (p = 0.174).(Figure 1)

In mifepristone group,84 % of patients deliver by labour natural compared to 67% in foley catheter group. The rate of caesarean section rate was only 16% in mifepristone group than compared to foley group which was 33%. This reduction in the rate of caesarean section among the two groups were found to be significant (p value<0.05). (Table 1). The mean induction to delivery interval was 26 hours as compared to 36 hours in foley’s induction group. This decrease in interval between the two groups was found to be significant (p value: <0.05) (Table 2)

The incidence of meconium stained liquor was 9% in mifepristone group when compared to 13% in the foley’s group. All the babies born with meconium stained liquor are vigorous only. This decline in the incidence of respiratory distress in newborn was found to be statistically significant (p value: < 0.05%). In this study the incidence of PPH was compared between the two groups which was found to be insignificant as the P value >0.05.

Figure 1: Parity With Type of Induction

Table 1: Association Between Type of Induction and Mode of Delivery:

 Chi-square test                                                                                 *P is <0.05

Table 2: Association between Induction delivery interval and Induction Types:

DISCUSSION

This observational randomized study was conducted at Coimbatore Medical College Hospital among 200 postdated pregnant women, comparing mifepristone and Foley’s catheter for induction of labour. Of the participants, 100 received mifepristone and 100 underwent Foley’s catheter induction; 135 were primigravida and 65 were multigravida, with a mean age of 24–25 years. A significant improvement in Bishop’s score was observed in both groups, similar to the findings of Atawale et al.³ and Fathima et al.,⁴ who also reported better cervical ripening with mifepristone compared to mechanical methods.

Vaginal delivery was higher in the mifepristone group (84%) compared to the Foley’s group (64%), while cesarean section rates were lower (16% vs. 33%). Comparable results were reported by Lata G et al.⁵ and Rutuja Atawale ⁶ et al., where vaginal delivery rates with mifepristone ranged around 75–85%, with reduced cesarean rates compared to Foley’s catheter. The mean induction–delivery interval in this study was shorter with mifepristone (26 hours) compared to Foley’s catheter (36 hours), which is in accordance with the study by Kannan Yelikar et al.,⁷ who also demonstrated a significantly reduced induction–delivery interval with mifepristone.

Neonatal respiratory distress was lower in the mifepristone group (3%) compared to the Foley’s group (12%), with no significant difference in overall perinatal outcomes or incidence of postpartum hemorrhage, similar to observations by Hapangama and Byrne et al.⁸ Overall, the findings support that mifepristone is more effective than Foley’s catheter in reducing cesarean section rates, shortening induction–delivery interval, and improving neonatal outcomes in postdated pregnancies.

CONCLUSION

 Mifepristone is a safe and effective method for induction of labour in postdated pregnancies when compared to Foley’s catheter. Mifepristone was associated with a shorter induction–delivery interval, higher rates of vaginal delivery, lower cesarean section rates, and reduced incidence of neonatal respiratory distress, with no significant difference in postpartum hemorrhage. Therefore, mifepristone can be considered a better alternative for cervical ripening and induction in postdated pregnancies, although further large-scale studies are recommended to confirm its safety profile and long-term outcomes.

BIBLIOGRAPHY

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