Analyzing caesarean sections through the Robson classification in Nigeria: a prospective nationwide study in referral level facilities.

Background: Over the past 30 years, there has been increased concern on rising caesarean section rates. However, the absence of reliable data on appropriateness of caesarean section for women in many countries, including Nigeria, poses a significant obstacle to understanding the use of caesarean and the quality of care surrounding caesarean section. The objective of this study was to analyse the caesarean section rates in specific obstetric populations to better understand the appropriateness of caesarean section by Robson Group in 56 referral-level facilities across Nigeria. Methods: Data from 179,463 women who gave birth in 56 referral-level facilities across Nigeria between 1 September 2019 and 31 August 2022 were analysed using the Robson classification and interpreted using the WHO Implementation Manual. Findings: Of the 158,246 women classified by Robson, 52,221 (33%) had caesarean section. Women with previous caesarean section (Group 5) were the largest contributors to overall caesarean section rate, accounting for 27.1% of all caesarean sections. This was followed by women with preterm birth (Group 10-17.1%). Women with term induced labour or those who had a pre-labour caesarean section also made substantial contributions to overall caesarean section rate (Group 2 (nullipara women)-12.8%; Group 4 (multipara women)-12.0%). When examining caesarean section rate within specific obstetric populations, Group 2 and Group 4 (nullipara and multipara women without previous caesarean section) had particularly high caesarean section rates-84.0% and 77.7%, respectively. Most of these were pre-labour caesarean sections: 83.9% (5620/6702) in Group 2 and 90.6% (5676/6263) in Group 4, few women in these obstetric populations had labour induction (16.1% in Group 2; 9.4% in Group 4). Among nulliparous women undergoing pre-labour caesarean section the main indications were hypertensive disorders (18.9%) and suspected contracted/inadequate pelvis (13.2%). For multiparous women, hypertensive disorders (15.0%) and placental conditions (11.9%) were the leading indications. Group 2a and Group 4a (women who had induction of labour) also had high caesarean section rates-45.9% and 24.6%, respectively. Interpretation: This nationwide programme shows a high caesarean section rate among women with a previous caesarean section, highlighting the importance of appropriate caesarean section use in nulliparous women to prevent caesarean section in future pregnancies. Women with term pregnancies without previous caesarean section had a high rate of caesarean section while the rate of labour induction in the same population of women was low. Among women who had an induction of labour, a substantial proportion had a caesarean section. There may be an opportunity to reduce caesarean rate by strengthening strategies to identify women who are good candidates for induction of labour and by fostering an environment that supports safe and successful induction. A multi-faceted approach is needed including adequate training for health workers, creating a calm birthing environment, ensuring health workforce capacity to monitor women during labour induction and ensuring access to quality medications all within a the context of a well-functioning and well-financed health-care system. Funding: This work was funded by MSD for Mothers; and UNDP/UNFPA/UNICEF/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction Programme (HRP), a co-sponsored programme executed by the World Health Organization (WHO).