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| ORIGINAL ARTICLE |
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| Year : 2022 | Volume
: 24
| Issue : 2 | Page : 131-137 |
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Cesarean sections conducted in a tertiary care hospital – An analysis as per robson's ten group classification system
Shilpa Asthana, PR Lele, Devdatt Pitale, G Sandeep
Department of Obstetrics and Gynaecology, INHS Asvini, Mumbai, Maharashtra, India
| Date of Submission | 14-Mar-2021 |
| Date of Decision | 14-Nov-2021 |
| Date of Acceptance | 17-Nov-2021 |
| Date of Web Publication | 01-Apr-2022 |
Correspondence Address:
(Dr) Shilpa Asthana
Department of Obstetrics and Gynaecology, INHS Asvini, Colaba, Mumbai - 400 005, Maharashtra
India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/jmms.jmms_39_21
Background: Over a past few decades, there has been an increase in cesarean section (CS) rates globally. The exponential rise in CS is a major contributory factor in both maternal and fetal morbidities. It is important to assess, analyze, and audit cesarean section rate and its indications, in obstetric care delivery units existing in every health-care system. This study was conducted to audit the rate of CS in our institute with a focus to optimize the indications of CS with an aim to help in reduction in cesarean deliveries in future. Materials and Methods: This retrospective observational study was conducted over a period of 1 year in a large tertiary care hospital. All patients who underwent cesarean section were categorized according to Robson Ten group Classification system. Results: In this study, a total number of deliveries in the given time period were 1062, of which 455 (42.84%) underwent CS. Among the total CS, n = 237 (52.08%) were elective and n = 218 (47.91%) were emergency CS. The highest contribution to the CS, according to Robson's TGCS, was Group 5 and Group 2 in this study. Group 9 had the lowest contribution to CS rate. The most common indication for emergency CS was nonreassuring fetal heart rate (n = 76, 34.86%); however, post-LSCS pregnancy attributed (n = 132, 55.70%) to elective CS. A total number of CS performed at term were 402 (88.35%) and preterm CS conferred to 53 (11.65%). Conclusion: There exists a significant concern toward the overuse of CS. A definitive protocol and optimization of indications for primary CS along with clinical and administrative efforts would aid in minimizing the CS rate. Furthermore, it must be noted that every effort should be made toward provision of CS in women warranting it, rather than achieving specific target goal.
Keywords: Cesarean audit, cesarean section, Robson's criteria
How to cite this article:
Asthana S, Lele P R, Pitale D, Sandeep G. Cesarean sections conducted in a tertiary care hospital – An analysis as per robson's ten group classification system. J Mar Med Soc 2022;24:131-7 |
How to cite this URL:
Asthana S, Lele P R, Pitale D, Sandeep G. Cesarean sections conducted in a tertiary care hospital – An analysis as per robson's ten group classification system. J Mar Med Soc [serial online] 2022 [cited 2023 Apr 1];24:131-7. Available from: https://www.marinemedicalsociety.in/text.asp?2022/24/2/131/342384 |
| Introduction | |  |
Childbirth is the most crucial event that occurs in a woman's life. Regardless, of the route of delivery, whether vaginally or by cesarean section, childbirth carries potential risks to a woman and her child.
In obstetrics, cesarean section (CS) has been the most common and oldest surgery performed worldwide. The word “Cesarean” is a Latin word that means “to cut.” Romans were the first to document CS as a procedure in medical sciences. There was a written law, during the ancient Roman times “Lex cesaria” which stated that if a pregnant woman died during childbirth, the baby had to be removed after cutting her womb, as the burial of a pregnant woman was not allowed as per religious custom of Romans during that era.
The most dramatic feature of modern obstetrics was the exponential increase in CS globally. This escalated growth in CS rates posed a major public health problem and also added an additional health risk for mother and child.[1],[2]
The World Health Organization (WHO) guidelines suggested that the ideal rate of CS for a country should be within 10%–15%.[3],[4] However, lately, there has been a sudden increase in CS rates globally. The main indications for CS have been previous cesarean delivery, labor dystocia, cephalopelvic disproportion, fetal malpresentation (breech presentation/transverse lie), and nonreassuring fetal heart pattern.
In both developed and developing countries, CS has become increasingly common mode of delivery. In October 2018, the largest case series of assessment of CS globally was reported by the Lancet Journal in the year 2015, which revealed a doubling of CS rate from (16.0 million births) in 2000 to 21.1% (29.7 million births) in 2015.[1] The tilt toward an increased rate of CS was influenced by several factors such as small family norm, increased maternal age, use of electronic fetal monitoring system, litigation related to maternal and fetal outcome during and after delivery, maternal request for operative intervention, and decreasing trends toward vaginal birth after cesarean and instrumental deliveries.
Similarly, the CS rate in India has shown an upward trend from 8.5% in 2005 to 17.2% in 2015 by Family Health Survey (NFHS) in India. The CS rate in public health facilities in India has increased from 7.2% in the NFHS-1 to 11.9% in the NFHS-4, whereas a noticeable increase has been documented from 12.3% to 40.9% in private health facilities in 2015. According to NHFS, about 29% of institutional births in India take place in a private sector hospital, but they contribute to 63% of all CS rates in the country, whereas 70% of deliveries are conducted at government hospitals in India which account for 35% of all CS rates.[5] In view of the rising trend in the CS rates, comprehensive focus and strategies need to be implemented along with periodic assessment in respective institutes to analyze, standardize, and optimize quality of care within the health-care facilities to reduce CS rates.
All patients who underwent cesarean section during the study period were categorized according to Robson Ten group Classification System (RTGCS) as described by MS Robson. This classification system for CS has been widely advocated and supported by Federation of Obstetrics and Gynecology and WHO for analyzing the CS within a health-care system.
RTGCS grouped all the CSs performed in this institute according to the following parameters – parity (with/without previous CS), period of gestation (>37/<36 weeks), fetal presentation (cephalic/breech/abnormal lie), number of fetuses (singleton/multiple), and onset of labor (spontaneous/induced/CS before onset of labor).
This classification system provides an excellent structured and conceptualized format for tabulation of data of CS which can be compared with the data available not only within different states in India but also globally.[3],[4],[6] Its simplicity and ease of analysis and interpretation would aid in optimizing the rate of CS. The assessment done by RTGCS helps in the identification of highest and lowest contributors for CS in specific groups, which eventually would help in formulating strategies to reduce CS rates in the desired group.
This study was conducted in this tertiary care institute with an aim to assess the rate of CS and contribution of each group toward the overall CS rate, followed by a definitive focus to reduce CS rate in our institute in future. The aim of this study is to determine CS rate in a large, tertiary care hospital over a 1 year period as per Robson's Ten Group Classification System (TGCS), and to identify the group with the least and the maximum contribution to overall CS rate, we have also tried to analyze the most common indication for emergency and elective CS and to determine the rate of CS performed at term and preterm gestation.
| Materials and Methods | | |
This was a retrospective observational study conducted for 1 year from January 2019 to December 2019, in the department of obstetrics and gynecology in a large tertiary care government teaching hospital at Mumbai. The ethical clearance was obtained from the standing hospital ethics committee before commencement of this study. The relevant documentations were undertaken pertaining to the obstetric history given by patients from available hospital records. All patients in the age group of 18–40 years, delivered by CS, were included in the study and tabulated according to Robson's TGCS.[4],[6] All patients who underwent instrumental and vaginal deliveries either at preterm or term gestation and those who underwent a trial of labor after CS (TOLAC) were excluded from the study. The pregnant patients who were included in this study were grouped in accordance with the five parameters as stated by Robson's TGCS. After the collection of data, the results were tabulated in percentage for each group.
| Results | | |
This study conducted within the stipulated time during 1 year recorded a total of 1062 deliveries in our institute. The patients who underwent CS were 455 (42.84%) and normal (vaginal) deliveries were 578 (54.42%), as depicted in [Table 1]. Of the patients who underwent CS, 237 (52.08%) were elective and 218 (47.91%) were emergency CS, as mentioned in [Table 2].
A total of 402 (88.35%) were at term and 53 (11.65%) underwent preterm CS, as depicted in [Table 2]. Robson's TGCS for CS is illustrated in [Table 3].
The patients included in this study group are then grouped in [Table 4], in accordance with Robson's Ten Group Classification for CS, as mentioned earlier. Class 1 included nulliparous women at term with singleton pregnancy, with cephalic presentation with spontaneous onset of labor, which contributed to 8.35%. Class 3 encased multiparous women at term, singleton without previous CS who went into spontaneous labor, accounting for 3.30% which was less than Group 1. | Table 4: Tabulation of result in each group as per Robson's Ten Group Classification of cesarean section
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Group 2 and Group 4 comprised nulliparous and multiparous patients, respectively, singleton pregnancy at term with cephalic presentation; in these subsets of patients, labor was induced or patients underwent CS before labor. Group 2 had 25.27% and 6.59% was noted in Group 4. The second highest percentage of CS rate in our study was found in Group 2.
Group 5 encompassed highest percentage of CS rate, i.e., 29.01%, which consisted of multiparous patients with singleton pregnancy at term ≥37 weeks of gestation and cephalic presentation with previous CS.
All nulliparous patients with breech presentation and multiparous with breech presentation (including previous CS) were incorporated into Group 6 and Group 7 with 7.47% and 2.64%, respectively. A total of 46 patients with breech presentation were delivered (34 primigravidae and 12 multigravidae) in this study period of 1 year. The patients with multiple pregnancies (including previous CS) were clustered in Group 8 which accounted for 4.83% of the total CS rate.
In Group 9, patients with abnormal lie (transverse or oblique lie) were integrated into this group, attributing to 0.88% of the total CS rate. Group 10 constituted all preterm pregnancies =<36 weeks of gestation with singleton and cephalic presentation (including previous CS). This group was responsible for the third largest contribution due to 11.65% of the total institutional CS rate during the study period. The highest rate of CS was seen in Group 5 by Robson's TGCS, followed by Group 2 and Group 10. The lowest rate of CS was observed in Group 9.
The distribution of age of the patients included in this study is depicted in [Figure 1]. The patients included in this study ranged between 18 and 40 years of age, with maximum patients within the age group of 25–29 years of age, equivalent to 63% and 3% of the mothers were in the advanced maternal age group (35–40 years). The birth weight distribution of neonates after CS is represented in [Figure 2]. Maximum number of neonates weighed between 2.1 and 3.0 kg which accounted for 47.91%, whereas 0.9% corresponded to extremely low birth weight (<1.0 kg) and 5% paralleled to neonates weighing more than 4.0 kg.
[Figure 3] and [Figure 4] describe the indications for elective CS and emergency CS, respectively. The highest contribution toward elective CS was from post-LSCS pregnancies which ascribed to n = 132 (55.70%), while the most common indication for emergency CS was nonreassuring fetal heart rate which credited to n = 76, 34.86%. A total number of CS performed at term were n = 402, 88.35% and preterm CS conferred to n = 53,11.65%, as shown in [Figure 5].
| Discussion | | |
In our institute, the CS audit was carried out to analyze the indications of CS with an emphasis to reduce CS rate in future. The CS was classified in accordance with Robson's Ten Group Classification, as mentioned in [Table 4]. The CS audit at this tertiary institute revealed that the rate of CS was 42.84% which is significantly higher than what is mentioned by the WHO, i.e., 10%–15%.
The increased rate in this tertiary care institute may be attributable to several factors, as our institute serves as a referral center for high-risk cases, i.e., pregnancy complicated by hypertensive disorders and severe preeclampsia, uncontrolled and overt diabetes, severe fetal growth restriction, and severe oligohydramnios. These high-risk pregnancies need management at a tertiary center, as it may necessitate intervention at an early gestation (preterm) and result in care of neonates at a well-equipped neonatal intensive care unit due to prematurity. Moreover, such high-risk cases cannot be managed appropriately with desired outcomes in a peripheral center due to unavailability or nonexistence of trained specialists (senior obstetricians and neonatologists with critical care anesthesiologists) and requisite infrastructure.
Furthermore, this center has a fully operational assisted reproductive technology (ART) center for infertility patients. The pregnancies through ART have an increased risk of preeclampsia, gestational diabetes, placenta praevia, multiple pregnancies, and perinatal morbidity and mortality (premature births and intrauterine demise), warranting aggressive evaluation and management. Hence, with an aim to achieve positive pregnancy outcome, there is an increased incidence of induction of labor and CS rates (both emergency and elective) in these subsets of patients. In this institute, 81 patients delivered post in vitro fertilization intervention, of which 66 underwent CS, 20 patients delivered vaginally, and two had instrumental delivery.
In the present study, the CS rate of this tertiary teaching hospital was 42.82% which is comparable to several studies conducted across various states in India. Banerjee et al. conducted a study in a tertiary center in Assam to audit CS rates for a time period of 8 years from 2010 to 2018, CS rate was found to be 34.1%. A study reported by Das et al. showed a CS rate of 35.45% at a tertiary center at Orissa in 2018. In a similar study performed at a tertiary care obstetric unit in Karnataka, Nagavarapu et al. revealed a CS rate of 44%. Other studies such as Kant et al. in Haryana, Rajiv Saxena and Balan in Bengaluru, and Yerra and Khan in Hyderabad enumerated the total CS rates in each institute as 53.86%, 46.7%, and 55%, respectively. A multicentric study, conducted by Boerma et al., reported an increasing rate of global CS, with wide disparities existing between countries ranging from highest rate of 55.9% in Brazil, 44.3% in Latin America and Caribbean region to as low as 4.1% in West and Central African region, the CS rate in US documented to be 32%, while 33%, 28%, and 35% CS rates were reported for Australia, Canada, and China individually.[3],[7],[8],[9],[10],[11],[12],[13]
In this study, about n = 237 (52.08%) were elective and n = 218 (47.91) were emergency CS. The most common indications for elective CS were previous CS (29.01%) and breech presentation (15.38%). Similar results were seen in Das et al. (29.96%) and Banerjee et al. (26.76%).[11],[13] In the present study, indications for elective CS were also inclusive of the following: multifetal gestation, placenta praevia, abnormal lie, fetal growth restriction, abnormal color Doppler velocimetry, and pregnancy complicated with medical disorders, for example, SLE, thrombophilia, hypertensive disorders, gestational diabetes, elderly gravida, prolonged period of infertility, or pregnancy following ART intervention. Nonreassuring fetal heart rate was the most common indication for emergency CS accounting for n = 76 (34.86%), followed by labor dystocia (n = 58, 26.60%), hypertensive disorders (severe preeclampsia/eclampsia) (n = 15, 6.88%), abruptio placentae (n = 11, 5.04%), and cord prolapse (n = 3,1.37%); various other indications such as severe fetal growth restriction, severe oligohydramnios, pregnancy with malpresentation or abnormal lie in active labor, and history of poor pregnancy outcome in previous pregnancy including those with no prior living issue and pregnancy complicated with medical disorders, for example, SLE, thrombophilia, hypertensive disorders, gestational diabetes, not responsive to induction of labor protocols for vaginal delivery, underwent emergency CS in this study. The indication for emergency CS with the highest contribution was noticed with nonreassuring fetal heart rate, and similar results were evident in studies by Banerjee et al., Arpitha and Asha, and Yerra and Khan attributing to 32.8%, 40.3%, and 44% independently.[8],[11],[14]
The study was conducted in this tertiary care institute as a retrospective analysis of deliveries in a time frame of 1 year by categorizing the CS s undertaken during this time period, in accordance with Robson TGCS. The categorization of CS was done with an aim to evaluate and understand the indication of CS in each group. This CS audit was undertaken to rationalize each indication in a given category and regulate the CS rate in the center for future use. The groups that contributed maximum and minimum to the CS rates were recorded.
The highest contribution was seen in Group 5 with 29.01%. Studies by Das et al. reported the contribution of CS in Group 5 as 29.96%, Banerjee et al. in 2018 showed 26.76%.[11],[13] CS rate of Group 5 was 33.9% in China and 32.7% in Brazil as described by Boerma et al.[7] Only six patients with previous CS consented for TOLAC (trial of labor after CS) and the remaining patients (132) in this group were unwilling for trial of labor.
In this study, Group 2 had the second highest contribution to CS rates accounting for 25.27%. Similar results were seen in Kant et al., a study conducted in 2018 at Faridabad which revealed 36.71%. Few studies in India have suggested Group 1 as the second highest contributors toward CS rates; for example, a study conducted in Hyderabad in 2020 by Yerra and Khan showed it as 19.3% in Group 1 and only 7.7% in Group 2. In 2019, a study conducted in tertiary care institute in Bengaluru by Saxena and Balan showed the contribution in Group 1 to be 26% and 15.9% for Group 2. Boerma et al. in 2018 stated that Robson Groups 1 and 2 contributed to 39.9% in China and 35.4% in Brazil to overall CS rates and were deemed as the largest contributor to the overall CS rates followed by Group 5.
Furthermore, in this study, Groups 6 and 7 for breech presentation (nulliparous and multiparous, respectively) had contributed to 10% of the total CS rate in our institute. A similar outcome was seen in a study conducted at Thrissur medical college in 2017, by Jacob et al. which was attributing to 13.1% of institutional CS rates. A study conducted by Sharma et al. in 2017 in Himachal Pradesh showed a contribution of breech delivery by CS of 12% to the total CS rate. However, Boerma et al. for breech presentation and malpresentation seen globally was quoted as 5%. In England and Wales, the National Sentinel CS audit report showed the CS rate for breech presentation as 10.8%. The increasing CS rate among women with breech presentation could be attributed to increased morbidity and mortality seen in vaginal breech deliveries, as stated by the term breech trial and meta-analysis of several observational studies. External cephalic version at term would be an effective approach to curtail the increased rate of CS rate in this group in absence of any contraindication for conduct of vaginal breech delivery.[15],[16],[17] However, no external cephalic version was attempted in patients included in this study.
In Group 10 in this study, all CSs were undertaken before 37 weeks of gestation women attributing 11.65% to the CS rates in this institute. Severe preeclampsia and eclampsia, severe fetal growth restriction, severe oligohydramnios, preterm premature rupture of membranes, and preterm labor were the main contributors to this group. Similar findings were seen in a study conducted by Yerra and Khan in a tertiary care teaching hospital in Hyderabad, contributing to 10% of the total CS rate in the institute; Kant et al. conducted a study in a tertiary care institute in Faridabad, where preterm CS contributed to 9.7% of the total CS rate, hile Boerma et al. stated 9.2% in Brazil and 5.5% in China. The CS in this group was imminent due to intervention required at preterm gestation to reduce both maternal and fetal morbidity and mortality due to existing obstetrical complications.[7],[8],[12]
The lowest contributor to the total CS rates of the institute was Group 9 (all pregnancies with transverse or oblique lie) with 0.88%. Similar incidence had been quoted in a study by Yerra and Khan as 0.6%, and Tanaka et al. 0.8%. As per Vogel et al., a multicentric study conducted in 21 countries globally reported 0.4%–0.6% of CS rate for transverse lie.[8],[9],[18]
In the present study, Group 8 contributed to 4.8% to the total CS rate. Similar rates were seen study by Kant et al. and Banerjee et al. which showed the CS rates contribution of multiple pregnancies as 3.14% and 2.7% individually. The rise in ART intervention due to infertility has also attributed to the incidence of multifetal gestation.[11],[12]
After a detailed analysis of CS in each group as per Robson's classification, maximum CS rates for this tertiary care hospital were from Group 5 (post-CS) followed by Group 2 (nulliparous at 37 weeks of gestation after induction). This CS audit revealed similar results in various tertiary care institutes in India. A multicentric study conducted across 21 countries in the world by Vogel et al. has also concluded the contribution of Group 5 toward the highest proportion of CS rates. The use of induction protocols in both nulliparous and multiparous women, i.e., Group 2 and Group 4, has shown increased CS rates when compared to women (both nulliparous and multiparous) in Group 1 and Group 3. Similar results have been quoted by several studies in the Indian context and across the world by Vogel et al. and Boerma et al. Total contribution toward CS rates from Group 1, 2, 3, 4, and 5 together accounted for 72.52% of total CS.
| Conclusion | | |
The incidence of CS in this study was noted to be 42.84% which was found to be significantly higher than elucidated by the WHO (10%–15%). It is important to monitor the modifiable indications for CS in Groups 1, 2, 3, and 4 so that the overall CS rate for the institute could be controlled to an extent. The reduction in primary CS for women in Groups 1, 2, 3, and 4 would affect the overall CS rates in Group 5 (post cesarean pregnancies). This would definitely serve to be a major step toward lowering CS rate in the institute.
It is pertinent to incorporate regular audits and definite protocols in hospitals to curb the CS rates in every obstetric care unit. CS would always undoubtedly, be an important mode of delivery in situations wherein maternal and fetal compromise is suspected. It is also noteworthy for every clinician to exert sustained efforts toward provision of indicated cesarean delivery to women whenever indicated rather than achieve a specific target.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]
[Table 1], [Table 2], [Table 3], [Table 4]
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