| Literature DB >> 31822545 |
Francesca Tognon1,2, Angela Borghero3, Giovanni Putoto2, Donald Maziku4, Giovanni Fernando Torelli3, Gaetano Azzimonti3, Ana Pilar Betran5.
Abstract
OBJECTIVE: Caesarean section (CS) rates have increased worldwide in recent decades. In 2015, the WHO proposed the use of the 10-group Robson classification as a global standard for assessing, monitoring and comparing CS rates both within healthcare facilities over time and between them. The aim of this study was to assess the pattern of CS rates according to the Robson classification and describe maternal and perinatal outcomes by group at the Tosamaganga Hospital in rural Tanzania.Entities:
Keywords: 10-group classification system; Robson classification; Tanzania; cesarean section; neonatal outcome
Mesh:
Year: 2019 PMID: 31822545 PMCID: PMC6924846 DOI: 10.1136/bmjopen-2019-033348
Source DB: PubMed Journal: BMJ Open ISSN: 2044-6055 Impact factor: 2.692
Characteristics of women delivered during the period from January to June 2014 and March to November 2015 in Tosamaganga Hospital, Tanzania (n=3012)
| Maternal age | |
| Mean | 25.6 |
| Range | 14–45 |
| Parity | |
| Nulliparous (%) | 1321(43.9%) |
| Multiparous (%) | 1691(56.1%) |
| Previous CS | |
| No previous CS (%) | 2493(82.8%) |
| One previous CS (%) | 370(12.3%) |
| Two previous CS (%) | 111(3.7%) |
| Three or more previous CS (%) | 38(1.3%) |
| Referral status | |
| Self-admitted (%) | 2844(94.4%) |
| Referred from other facilities (%) | 168(5.6%) |
CS, caesarean section.
The Robson reporting table and neonatal outcomes by Robson group, Tosamaganga Hospital, Tanzania, January–June 2014 and March–November 2015
| Group* | Number of CS in group | Number of women in group | Group size (%) | Group CS rate (%) | Absolute group contribution to overall CS rate (%) | Relative contribution of group to overall CS rate (%) | Stillbirth(N stillbirth/N women (%)) | Early neonatal death†(N neonatal deaths/N women (%)) | Apgar <7 at 5 min(N live birth Apgar <7/N women (%)) | |
| 1 | Nulliparous, single cephalic, term pregnancy, in spontaneous labour | 309 | 1128 | 37.5 | 27.4 | 10.3 | 29.2 | 9(0.8) | 28(2.5) | 24(2.1) |
| 2 | Nulliparous, single cephalic, term pregnancy, induced labour or elective CS | 35 | 56 | 1.9 | 62.5 | 1.2 | 3.3 | 8(14.3) | – | 1(1.8) |
| 3 | Multiparous (excluding previous CS), single cephalic, term pregnancy, in spontaneous labour | 147 | 974 | 32.3 | 15.1 | 4.9 | 13.9 | 16 (16) | 13(1.3) | 13(1.3) |
| 4 | Multiparous (excluding previous CS), single cephalic, term pregnancy, induced labour or elective CS | 25 | 45 | 1.5 | 55.6 | 0.8 | 2.4 | 7(15.6) | – | 1(2.2) |
| 5 | One previous CS, single cephalic, term pregnancy | 404 | 463 | 15.4 | 87.3 | 13.4 | 38.1 | 5(1.1) | 2(0.4) | 8(1.7) |
| 6 | All nulliparous breeches | 13 | 21 | 0.7 | 61.9 | 0.4 | 1.2 | 2(9.5) | 2(9.5) | 3(14.3) |
| 7 | All multiparous breeches (including previous CS) | 16 | 32 | 1.1 | 50.0 | 0.5 | 1.5 | 5(15.6) | 4(12.5) | – |
| 8 | All multiple pregnancies (including previous CS) | 48 | 77 | 2.6 | 62.3 | 1.6 | 4.5 | 3(3.9) | 7(9.1) | – |
| 9 | All abnormal lies (including previous CS) | 30 | 30 | 1.0 | 100.0 | 1.0 | 2.8 | 1(3.3) | 1(3.3) | 3(10) |
| 10 | All single cephalic, preterm (including previous CS) | 33 | 186 | 6.2 | 17.7 | 1.1 | 3.1 | 22/11.8) | 17(9.1) | 15(8.1) |
| Total | 1060 | 3012 | 100 | 35.2 | 35.2 | 100 | 78(2.6) | 74(2.5) | 68(2.3) | |
Unclassifiable: 40 cases, 1.3% (40/3052).
*Birth weight ≥2500 g was used as proxy for gestational age >37 weeks
†Early neonatal death was defined as the death of a live born neonate, by discharge or day 7 of life (whichever occurred first)
CS, caesarean section.
Interpretation of the Robson classification in Tosamaganga Hospital, Tanzania, January– June 2014 and March–November 2015 following the WHO Robson Classification Interpretation Manual
| Quality of data |
The CS rate of the group is 100% indicating a good quality of data. |
| Type of population |
The size of groups 1 and 2 (39.5%) is within the expected range. However, the ratio of the size of group 1vs that of group 2 is very high (20.1). In the WHO Multicountry Study reference population (population in the WHO study with relatively low CS rates as well as good labour and childbirth outcomes), this ratio was found to be 6.3. The size of groups 3 and 4 is 33.9%. Since Tanzania has a high fertility rate, we expected a higher number of multiparous women. This can be explained by the very high size of group 5 (15.4%) with a CS rate of 87%, which contributes to about 38% of all the CS performed in the hospital. The size groups 6 and 7 is 1.6%, which is below the expected range for breeches. Moreover, the ratio of group 6/group 7 (0.5) is unusual since breeches are more frequent in nulliparas than multiparas. This could indicate errors in data collection potentially due to misclassification of nulliparous women with breech presentation into group 1. The size of group 10 is 6.2% that is slightly higher than that proposed by Robson (5%) and that found in the WHO Study (4.2%). Even if Tosamaganga Hospital is a referral hospital, only 168 women (5.6%) were referred, 107 (63.7%) of whom delivered by CS. For this reason, we consider that the larger sizes of groups 8 and 10 cannot be justified by a particularly high-risk population. Malnutrition and other concurrent diseases may have caused growth retardation and errors in pregnancy dating based on neonatal weight. |
| Caesarean section rate |
In all groups, the CS rates are higher than the expected range. It has been proposed that CS rates in group 1 of about 10% are achievable. However, the above-mentioned high ratio of group 1vsgroup 2 may be responsible for the high CS rate(27.4%) in this group. If insufficient numbers of women are induced or have necessary pre-labour CS, it is more likely that these women will need a CS at a later stage of labour. In addition, the high CS rate in group 2 is not caused by the size of group 2b (pre-labour CS, only 0.8% of the population), but mainly by a very low size of group 2a (1.1% of the population) and by the poor success for induction with a consequent high C/S rate (34.4%) in this group as well. Similar arguments apply to groups 3 and 4. The high CS rate in group 4 (55.5%) is not justified by the high size of group 4b (which accounted for only 0.8% of the population), but by the small size of group 4a (just 0.7% of the population). Particularly in groups 1 and 3, a large number of CS were performed with the diagnosis of dystocia. This might indicate a poor quality of diagnosis of dystocia and suboptimal management of the active phase of labour. The very high CS rate in group 5 (87.2%) is not justified by the proportion of women with two or more CS (group 5.2) who make up one-third of this group. CS rates in women with one CS (group 5.1) and two or more CS (group 5.2) are both high (83.2% and 97%, respectively), indicating the common practice of performing CS in women with previous scar. These rates contrast markedly with the 50%–60% rates considered appropriate by the Robson guideline and the 74.4% found in the WHO Study. Looking at the higher-risk groups, the CS rate in group 8 is within the expected range, while the CS rate in group 10 is lower than expected, probably indicating a high rate of spontaneous preterm labour or a high incident of low birth weight (since newborn weight was used as a proxy for gestational age). Considering the contribution of the groups to the overall CS rate, groups 1, 2 and 5 account for 70.6% of all CS, a higher percentage than expected, and of that figure, group 5 accounts for 38.1% indicating, as already mentioned, a very high CS rate in the previous years. |
CS, caesarean section; VBAC, vaginal birth after caesarean.
Indication for CS in the study population, Tosamaganga Hospital, Tanzania, January–June 2014 and March–November 2015
| Previous scar | 416 | 39.2% |
| Mechanical or dynamic dystocia | 236 | 22.3% |
| Fetal distress | 136 | 12.8% |
| Breech | 22 | 2.1% |
| Twins | 28 | 2.6% |
| Malpresentation | 41 | 3.9% |
| CPD | 90 | 8.5% |
| Urgent or emergency CS | 50 | 4.7% |
| Others | 41 | 3.9% |
| Total number of CS | 1060 | 100.0% |
CPD, cephalopelvic disproportion; CS, caesarean section.
Figure 1Management of women with one or more previous caesarean sections during the study period.
Figure 2Indication for caesarean sectionin groups1 and 3.
Distribution of severe neonatal* outcomes by Robson group classification
| Group | Number of severe neonatal outcomes/number of women in group | Proportion of severe neonatal outcomes | Relative contribution of group to the overall severe neonatal outcomes | Proportion of severe neonatal outcome in simple vaginal deliveries† / total simple vaginal deliveries | Proportion of severe neonatal outcome in operative vaginal deliveries‡ / total operative vaginal deliveries | Proportion of severe neonatal outcome in CS / total CS | |||
| 1 | 61/1128 | 5.4% | 27.7% | 43/799 | 5.4% | 1/20 | 5.0% | 17/309 | 5.5% |
| 2 | 9/56 | 16.1% | 4.1% | 7/19 | 36.8% | 0/2 | 0.0% | 2/35 | 5.7% |
| 3 | 42/974 | 4.3% | 19.1% | 27/818 | 3.3% | 1/9 | 11.1% | 14/147 | 9.5% |
| 4 | 8/45 | 17.8% | 3.6% | 7/20 | 35.0% | – | – | 1/25 | 4.0% |
| 5 | 15/463 | 3.2% | 6.8% | 1/58 | 1.7% | 0/1 | 0.0% | 14/404 | 3.5% |
| 6 | 7/21 | 33.3% | 3.2% | 6/8 | 75.0% | – | – | 1/13 | 7.7% |
| 7 | 9/32 | 28.1% | 4.1% | 7/16 | 43.8% | – | – | 2/16 | 12.5% |
| 8 | 10/77 | 13.0% | 4.5% | 4/29 | 13.8% | – | – | 6/48 | 12.5% |
| 9 | 5/30 | 16.7% | 2.3% | – | – | – | 5/30 | 16.7% | |
| 10 | 54/186 | 29.0% | 24.5% | 47/153 | 30.7% | – | – | 7/33 | 21.2% |
| Total | 220/3012 | 7.3% | 100.0% | 149/1920 | 7.8% | 2/32 | 6.3% | 69/1060 | 6.5% |
*Severe neonatal outcome includes stillbirths, neonatal deaths and live births with Apgar score <7 after 5 min.
†Simple vaginal delivery: vaginal deliveries not requiring forceps or vacuum, though episiotomy may have been done.
‡Operative vaginal delivery: vaginal deliveries that required forceps or vacuum.
CS, caesarean section.
The Robson classification table showing only the subdivisions in groups 2, 4 and 5, Tosamaganga Hospital, Tanzania, January–June 2014 and March–November 2015
| Group* | Number of CS in group | Number of women in group | Group size (%) | Group CS rate (%) | Absolute group contribution to overall CS rate (%) | Relative contribution of group to overall CS rate (%) | |
| 2a | Nulliparous, single cephalic, S37 weeks, induced | 11 | 32 | 1.1 | 34.4 | 0.4 | 1.0 |
| 2b | Nulliparous, single cephalic, S37 weeks, CS before labour | 24 | 24 | 0.8 | 100.0 | 0.8 | 2.3 |
| 4a | Multiparous (excluding previous CS), single cephalic, S37 weeks, induced | 1 | 21 | 0.7 | 4.8 | 0.0 | 0.1 |
| 4b | Multiparous (excluding previous CS), single cephalic, S37 weeks, CS before labour | 24 | 24 | 0.8 | 100.0 | 0.8 | 2.3 |
| 5.1 | One previous CS, single cephalic, S37 weeks | 272 | 327 | 10.9 | 83.2 | 9.0 | 25.7 |
| 5.2 | Two or more previous CS, single cephalic, S37 weeks | 132 | 136 | 4.5 | 97.1 | 4.4 | 12.5 |
*Birth weight ≥2500 g was used as proxy for gestational age >37 weeks.
CS, caesarean section.