Scheduled versus on-demand nonopioid analgesia after cesarean delivery under regional anesthesia: a meta-analysis of randomized controlled trials

Manupriya Madhavan; K Pushpalatha; Kumar Madhavan; Amrut Phonde

doi:10.17085/apm.26511

Madhavan, Pushpalatha, Madhavan, and Phonde: Scheduled versus on-demand nonopioid analgesia after cesarean delivery under regional anesthesia: a meta-analysis of randomized controlled trials

Review

Anesthesia and Pain Medicine 2026;apm.26511.

Published online: July 9, 2026

DOI: https://doi.org/10.17085/apm.26511

Scheduled versus on-demand nonopioid analgesia after cesarean delivery under regional anesthesia: a meta-analysis of randomized controlled trials

Manupriya Madhavan¹

, K Pushpalatha²

, Kumar Madhavan³

, Amrut Phonde³

¹Department of Obstetrics and Gynaecology, Sri Satya Sai University of Technology and Medical Sciences, Sehore, India

²Department of Obstetrics and Gynaecology, All India Institute of Medical Sciences, Bhopal, India

³Department of Urology, All India Institute of Medical Sciences, Bhopal, India

Corresponding author Kumar Madhavan, M.B.B.S., M.S., M.Ch., M.R.C.S., F.R.C.S. Department of Urology, All India Institute of Medical Sciences, Saket Nagar, Habib Ganj, Bhopal 462020, India
Tel: +91-755-2835085 E-mail: madhavanranjit@gmail.com

Current affiliation: Kumar Madhavan Department of Urology, All India Institute of Medical Sciences, Bhopal, India

Received January 4, 2026 Revised February 11, 2026 Accepted March 19, 2026

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Effective pain relief after cesarean delivery is crucial for maternal comfort, recovery, and breastfeeding. Although scheduled nonopioid analgesics are standard, on-demand regimens have been suggested to reduce drug exposure. PubMed/MEDLINE, Embase, Scopus, and Cochrane CENTRAL were systematically searched from inception to August 20, 2025, for randomized controlled trials (RCTs) comparing scheduled vs. on-demand nonopioid analgesia following cesarean delivery. The primary outcomes were postoperative pain intensity and analgesic consumption. Three RCTs that included 666 women were identified. At 24 h, scheduled dosing significantly reduced pain scores compared with on-demand regimens (mean difference [MD] 0.98, 95% confidence interval [CI] 0.55 to 1.41; P < 0.001, I² = 78%), but no difference was observed at 48 h (MD 0.76, 95% CI -0.30 to 1.82; P = 0.16, I² = 96%). Overall analgesic consumption did not differ significantly between groups (standardized MD -0.23, 95% CI -0.62 to 0.16, P = 0.24; I² = 80%). Maternal adverse effects were rare and similar across groups (risk difference −0.01, 95% CI −0.04 to 0.02; I² = 0%). Breastfeeding outcomes were inconsistently defined, with two trials indicating benefits from scheduled dosing. Neonatal safety outcomes were reported in one trial, showing no differences between groups. Scheduled nonopioid analgesia after cesarean delivery under regional anesthesia was linked to better pain control during the first postoperative day. After this period, the comparative effectiveness of scheduled vs. on-demand regimens remained uncertain, with considerable variability across studies. No significant differences were found in analgesic consumption or maternal adverse effects.

Keywords: Analgesia; Analgesia, obstetrical; Delivery, obstetric; Meta-Analysis; Postoperative pain; Randomized controlled trial

INTRODUCTION

Cesarean delivery is among the most common surgeries worldwide, and effective postoperative pain management is crucial for maternal comfort, early mobility, breastfeeding, and psychological health [1,2]. Poor pain control after a cesarean can delay recovery, increase the risk of blood clots, hinder mother-infant bonding, and negatively impact breastfeeding initiation [3,4].

Standard postoperative care in most centers involves the scheduled (around-the-clock) administration of nonopioid analgesics such as acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs). This approach aims to maintain consistent plasma drug levels, lessen breakthrough pain, and reduce opioid use. Consequently, scheduled dosing has become a common part of multimodal pain management after regional anesthesia for cesarean delivery [3-6].

However, the on-demand or pro re nata (PRN) approach has been suggested as an alternative. In this model, women receive analgesics only when the pain becomes significant, potentially reducing overall drug exposure and side effects. The tradeoff, however, is the risk of delayed or inadequate analgesia as patients may not request medication until the pain is severe. Whether PRN protocols can provide comparable pain relief while lowering the drug burden and ensuring maternal and neonatal safety remains unclear [7,8].

To address this uncertainty, a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing scheduled and on-demand nonopioid analgesic protocols following cesarean delivery under regional anesthesia was conducted. The primary outcomes were pain intensity and analgesic dosage.

METHODS

The Population, Intervention, Comparison, Outcomes, and Study design (PICOS) method was used to define inclusion and exclusion criteria [9]. RCTs that compared scheduled (fixed-interval, around-the-clock) vs. on-demand administration of nonopioid analgesics for women undergoing cesarean delivery under regional anesthesia were included. Eligible interventions comprised paracetamol, acetaminophen, NSAIDs, or combinations of these, administered orally, intravenously, or via mixed routes. Background multimodal analgesia, including regional techniques or rescue opioid use, was permitted, provided the only difference between groups was the analgesic administration strategy (scheduled vs. on-demand). Studies were eligible if they reported at least one of the following outcomes: postoperative pain intensity (measured using the visual analogue scale [VAS], numeric rating scale, or equivalent), analgesic consumption (dose, number of administrations, or opioid equivalents), maternal satisfaction, maternal adverse effects, functional recovery, breastfeeding outcomes (initiation, exclusivity, or time to lactation), or neonatal safety. The primary outcomes were postoperative pain intensity and analgesic consumption. The secondary outcomes comprised maternal satisfaction, adverse effects, breastfeeding outcomes, and neonatal safety. Trials were excluded if they were observational or quasi-experimental, if they compared different analgesic drugs or doses rather than administration strategies, if cesarean delivery was performed only under general anesthesia, or if relevant outcome data could not be extracted.

A comprehensive search of the PubMed/MEDLINE, Embase, Scopus, and Cochrane Central Register of Controlled Trials (CENTRAL) databases was conducted on August 20, 2025, from inception. The search strategy included keywords related to “cesarean section,” “analgesia,” “scheduled administration,” “on-demand analgesia,” “nonopioid analgesics,” and “RCTs.” The exact search strategy is provided in Supplementary Data 1. References of shortlisted articles and review articles were also searched for studies meeting our inclusion criteria. In addition, databases of ongoing trials, including clinicaltrials.gov and the Clinical Trials Registry of India, were searched for data from ongoing RCTs. Two authors (KM and MM) independently extracted the data, which were reviewed by the third author (KP). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed [10]. The study was registered with PROSPERO under registration number CRD420251074350 [11].

The risk of bias was evaluated using the Cochrane Risk of Bias (RoB) 2 tool [12]. Heterogeneity was assessed with the I² statistic (values > 50% indicate significant heterogeneity) and the variance of the random effect (Tau-squared statistic) [13]. Owing to the limited number of included trials, formal subgroup meta-analyses were not conducted. Sensitivity analyses employed a leave-one-out method to evaluate the robustness of pooled estimates and examine how individual studies influenced effect sizes and heterogeneity. Publication bias was checked using funnel plots, depending on the number of studies included [14]. The certainty of evidence was rated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) criteria [15].

Data were extracted from all included studies into standardized forms and then imported into Microsoft Excel for Mac 2021 (Microsoft) and RevMan Web (Cochrane Collaboration). For studies reporting medians and interquartile ranges, means and standard deviations (SDs) were imputed using Wan et al. [16]’s formula. Fixed effects models were used to synthesize results in the absence of heterogeneity; otherwise, a random effects model was applied.

Standardized mean difference (SMD) or mean difference (MD) and 95% confidence interval (CI) were used as the effect measure and measure of variance, respectively, for continuous variables. The risk difference (RD) and 95% CI were used to assess the risk of adverse events. P value < 0.05 was considered significant for all comparisons. Post hoc power was calculated using G*Power 3.1.9.4) [17,18]. The PRISMA checklist is given in Supplementary Data 2.

RESULTS

Our search identified three RCTs, which were included in our meta-analysis according to the PRISMA diagram in Fig. 1 [19-21]. A total of 4,152 records were retrieved; after screening, three RCTs met the inclusion criteria for this meta-analysis (Fig. 1). All three trials involved women undergoing cesarean delivery under regional anesthesia who were randomly assigned to receive either scheduled (fixed-interval) or on-demand (as-needed) nonopioid analgesia. The primary outcome reported across all studies was postoperative pain intensity, measured using the VAS. Analgesic consumption was also consistently reported, although in different formats: number of doses in Yefet et al. [19] and Dafna et al. [20], and cumulative oxycodone dose from patient-controlled analgesia (PCA) records in Li et al. [21] Yefet et al. [19] and Dafna et al. [20] reported breastfeeding outcomes, whereas Li et al. [21] additionally evaluated functional recovery, including time to ambulation, bowel recovery, and initiation of lactation. All three studies enrolled healthy parturients undergoing elective cesarean delivery, with comparable baseline characteristics between groups. The key baseline parameters of the included trials are summarized in Table 1 and Supplementary Data 3.

Across the three trials, 352 women were randomized to scheduled analgesia and 314 to on-demand analgesia. For the 24-h pain analysis, this randomization provided ≥ 99% power to detect a 1-point VAS difference between groups at α = 0.01 under conservative SD assumptions (SD = 1.5-2.5) and 95.6% power even with SD = 3.0. RoB 2 assessments were conducted for all studies and outcomes, and none were judged to be high risk (Fig. 2). Publication bias could not be definitively assessed because only three studies were included. Therefore, common methods such as funnel plots and Egger’s test were not suitable, given the small number of studies. The certainty of evidence was reduced due to the limited number of studies across all outcomes, as assessed using the GRADE approach (Supplementary Data 4).

PAIN SCORES

All three RCTs reported postoperative pain intensity using the VAS. On Day 1 (24 h), scheduled administration of nonopioid analgesics was associated with significantly lower pain scores compared with on-demand regimens (MD 0.98, 95% CI 0.55-1.41; P < 0.001, Fig. 2). Heterogeneity among studies was moderate to high (I² = 78%). Both Dafna et al. [20] and Yefet et al. [19] demonstrated clinically relevant reductions with scheduled dosing, whereas Li et al. [21] reported a smaller but still statistically significant effect.

On Day 2 (48 h), the pooled analysis did not show a statistically significant difference between the two regimens (MD 0.76, 95% CI -0.30 to 1.82; P = 0.16, Fig. 3). Heterogeneity was substantial (I² = 96%). Given the high heterogeneity, sensitivity analyses were performed for both pain scores on Day 1 and Day 2. However, this analysis did not change the results or heterogeneity, and no single study was responsible for the outcomes.

ANALGESIC CONSUMPTION

All three RCTs reported analgesic consumption, although their definitions of outcomes differed. Dafna et al. [20] reported the number of analgesic doses given, Yefet et al. [19] documented the number of rescue Percocet tablets used, and Li et al. [21] reported the total oxycodone consumption (mg) from PCA logs. To allow for pooling, data were combined using SMD. Our meta-analysis did not find a significant difference in overall analgesic use between scheduled and on-demand regimens (SMD -0.23, 95% CI -0.62 to 0.16; P = 0.24, Fig. 4). Heterogeneity was moderate to high (I² = 80%). Individually, Dafna et al. [20] observed higher total doses in the scheduled group, whereas Yefet et al. [19] reported nearly identical rescue opioid use between groups. Li et al. [21] found slightly lower cumulative oxycodone use in the scheduled group; however, this difference was not statistically significant. Again, sensitivity analysis did not change the results or heterogeneity.

MATERNAL ADVERSE EFFECTS

All three RCTs reported maternal adverse events, although the definitions differed slightly across studies. Reported adverse effects included gastrointestinal discomfort, nausea, vomiting, dizziness, and sedation. When combined, no significant difference was noted in the occurrence of adverse events between scheduled and on-demand analgesia (RD = -0.01, 95% CI -0.04 to 0.02; P = 0.56, Fig. 5). Heterogeneity was low (I² = 0%), indicating consistent results across the trials.

Individually, both Dafna et al. [20] and Li et al. [21] reported no adverse events in either group, whereas Yefet et al. [19] observed similar rates of minor adverse events between groups (11% vs. 9%). Overall, these results signify that the scheduled administration of nonopioid analgesics does not increase maternal adverse effects compared with on-demand dosing.

MATERNAL SATISFACTION

Two trials (Li et al. [21] and Yefet et al. [19]) reported maternal satisfaction with analgesia. The pooled analysis of 539 women (268 scheduled vs. 271 as-needed) revealed no significant difference in satisfaction scores between groups (MD -0.38, 95% CI -1.16 to 0.40; P = 0.34, Supplementary Fig. 1). Heterogeneity was substantial (I² = 93%), mainly due to divergent results: Li et al. [21] reported nearly identical satisfaction across groups, whereas Yefet et al. [19] found higher satisfaction among women receiving scheduled analgesia.

FUNCTIONAL RECOVERY

Functional recovery was only evaluated in Li et al. [21]’s study. Scheduled use of ibuprofen was linked to earlier bowel recovery, but no difference was observed in ambulation. Neither Yefet et al. [19] nor Dafna et al. [20] reported outcomes related to functional recovery. Dafna et al. [20] reported a significantly longer hospital stay in the on-demand group compared with the scheduled group (4.1 vs. 3.9 days; P value =0.05).

BREASTFEEDING OUTCOMES

Breastfeeding was assessed in all three trials, although the definitions varied. Yefet et al. [19] reported higher exclusive breastfeeding rates in the scheduled group, with a decreased need for supplemental formula. Dafna et al. [20] observed higher rates of breastfeeding initiation and exclusivity with scheduled dosing. Li et al. [21] measured the time to lactation initiation, which was similar between groups (72 h vs. 71.5 h). Owing to outcome heterogeneity, the data were summarized narratively rather than pooled. Overall, scheduled dosing appeared to support breastfeeding initiation and exclusivity in two trials, whereas the time to lactation showed no difference in the third trial.

NEONATAL OUTCOMES

Only Yefet et al. [19] systematically reported neonatal safety outcomes, including irritability, sedation, bilirubin levels, and the need for phototherapy. No significant differences were found between groups. Dafna et al. [20] and Li et al. [21] did not provide neonatal outcome data. The certainty of evidence was assessed using the GRADE approach and is furnished in Supplementary Data 4.

DISCUSSION

This systematic review and meta-analysis of three RCTs assessed the efficacy and safety of scheduled vs. on-demand nonopioid analgesic protocols after cesarean delivery under regional anesthesia. The main findings were that scheduled dosing provided better pain control at 24 h, but the difference was not statistically significant at 48 h. Scheduled dosing did not significantly change overall analgesic use or maternal adverse effects, and results on maternal satisfaction and breastfeeding outcomes were inconsistent across studies.

Our analysis revealed a meaningful clinical reduction in pain scores at 24 h with scheduled dosing, nearly a 1-point difference on the VAS scale. However, by 48 h, the difference was not statistically significant owing to high variability across studies. Despite lower pain scores, scheduled dosing did not decrease overall analgesic use when data from all studies were combined. This observation could be attributed to methodological differences: Li et al. [21] measured opioid doses in milligrams, Yefet et al. [19] counted rescue Percocet tablets, and Dafna et al. [20] reported total doses of multiple medications. These differences made comparison difficult. In addition, scheduled dosing results in higher total analgesic doses naturally. Nonetheless, scheduled protocols did not increase the incidence of adverse events. In a sample of > 650 women, maternal side effects such as nausea, vomiting, dizziness, or sedation were infrequent and occurred at similar rates in both groups [19-21].

Significant heterogeneity was observed for several outcomes, particularly 48-h pain scores and maternal satisfaction. This variability likely reflects key clinical differences between trials, including variations in analgesic regimens (single-agent NSAIDs vs. multimodal combinations), routes and timing of administration, and background opioid use. To assess the robustness of our results, leave-one-out sensitivity analyses were conducted for the main outcomes. These analyses showed that the direction of the effect at 24 h consistently favored scheduled dosing; however, the effect size and heterogeneity remained unchanged when any single study was excluded. This finding indicates that the pooled estimates were not driven by a single dominant study. Given the small number of trials included, these analyses were exploratory and underpowered.

Maternal satisfaction with analgesia varied across trials. While Yefet et al. [19] reported higher satisfaction with scheduled regimens, Li et al. [21] found no difference. These inconsistencies may stem from cultural differences in pain-relief expectations, variations in background multimodal protocols, or differences in the tools used to measure satisfaction. Functional recovery was only reported by Li et al. [21], who showed earlier bowel recovery with scheduled ibuprofen but no difference in ambulation. Data on length of stay were limited, although Dafna et al. [20] indicated a modest reduction with scheduled regimens.

The definitions and measurements of breastfeeding outcomes varied widely. Both Yefet et al. [19] and Dafna et al. [20] reported higher initiation and exclusivity rates in the scheduled groups, whereas Li et al. [21] found no difference in the time to lactation initiation. These findings should therefore be interpreted cautiously. Neonatal outcomes were rarely reported: only Yefet et al. [19] assessed bilirubin levels, the need for phototherapy, and neonatal behavior, finding no differences between groups. The limited neonatal data available prevent definitive conclusions about neonatal safety.

Our findings align with current Enhanced Recovery After Cesarean guidelines, which recommend scheduled acetaminophen and NSAIDs as the core of multimodal pain management. The Society for Obstetric Anesthesia and Perinatology consensus emphasizes that regular dosing of nonopioid pain relievers decreases breakthrough pain and opioid use in the immediate postoperative period. This finding supports the benefits observed at 24 h and highlights that scheduled regimens remain the best practice during the period of highest pain intensity [22].

Beyond obstetrics, several studies in general surgical populations have similarly demonstrated that scheduled nonopioid dosing reduces analgesic variability and enhances patient comfort compared with PRN regimens [6]. Inadequate pain control has been shown to hinder breastfeeding initiation and exclusivity, while maternal comfort is vital for successful mother-infant bonding [23-25]. Our findings indicate that scheduled nonopioid dosing offers better pain relief in the first 24 h after cesarean delivery without increasing adverse events. Although benefits for maternal satisfaction and breastfeeding are possible, the evidence remains inconsistent. Given the common practice of scheduled dosing, future trials could focus on pragmatic or noninferiority designs that evaluate alternative dosing strategies beyond the initial postoperative period, using standardized outcome measures and longer-term follow-up.

STRENGTHS AND LIMITATIONS

Our meta-analysis followed a pre-registered protocol, the RoB 2 tool, and assessed evidence certainty with GRADE. However, there were some limitations. Only three RCTs with modest sample sizes were available, which limited the accuracy of the pooled estimates and prevented a formal assessment of publication bias. Heterogeneity was significant for several outcomes, especially pain at 48 h and satisfaction, owing to differences in interventions, outcome definitions, and cultural contexts. Neonatal outcomes were poorly reported, restricting conclusions about infant safety.

A key limitation was that analgesic consumption was measured using SMDs. The reason was that the included studies reported this outcome in incompatible units, which limited the clinical interpretability of absolute drug exposure and prevented conversion to a common metric such as morphine equivalents.

CONCLUSION

In randomized trials, scheduled nonopioid analgesia after cesarean delivery under regional anesthesia was associated with lower pain scores during the first postoperative day. Beyond this initial period, the comparative effectiveness of scheduled vs. on-demand regimens remained uncertain, with significant variability across studies. No definitive differences were found in overall analgesic use or maternal adverse effects. Evidence on breastfeeding and neonatal outcomes was limited and inconsistently reported.

SUPPLEMENTARY MATERIALS

Supplementary data is available at https://doi.org/10.17085/apm.26511.

Supplementary Data 1.

Search strategy

apm-26511-Supplementary-Data-1.pdf

Supplementary Data 2.

PRISMA 2020 checklist

apm-26511-Supplementary-Data-2.pdf

Supplementary Data 3.

Baseline data of all studies

apm-26511-Supplementary-Data-3.pdf

Supplementary Data 4.

Summary of findings and certainty of evidence as per GRADE criteria

apm-26511-Supplementary-Data-4.pdf

Supplementary Fig. 1.

Forest plot of maternal satisfaction.

apm-26511-Supplementary-Fig-1.pdf

Notes

FUNDING

None.

CONFLICTS OF INTEREST

No potential conflict of interest relevant to this article was reported.

DATA AVAILABILITY STATEMENT

The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

AUTHOR CONTRIBUTIONS

Conceptualization: Manupriya Madhavan, Kumar Madhavan. Data curation: Kumar Madhavan. Formal analysis: Kumar Madhavan, Amrut Phonde. Methodology: Manupriya Madhavan, Amrut Phonde. Project administration: Kumar Madhavan. Visualization: Manupriya Madhavan. Writing - original draft: Kumar Madhavan, Amrut Phonde. Writing - review & editing: Kumar Madhavan, K Pushpalatha. Investigation: Manupriya Madhavan, Amrut Phonde. Resources: Kumar Madhavan. Software: Kumar Madhavan. Supervision: Manupriya Madhavan, Kumar Madhavan. Validation: K Pushpalatha, Kumar Madhavan.

Fig. 1.

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) diagram of our meta-analysis.

Fig. 2.

Forest plot of pain score at 24 h. SD: standard deviation, IV: inverse variance, CI: confidence interval, DL: DerSimonian-Laird. *IV group. **Oral group.

Fig. 3.

Forest plot of pain score at 48 h. SD: standard deviation, IV: inverse variance, CI: confidence interval, DL: DerSimonian-Laird. *IV group. **Oral group.

Fig. 4.

Forest plot of analgesic consumption. SD: standard deviation, Std.: standard, IV: inverse variance, CI: confidence interval, DL: DerSimonian-Laird. *IV group. **Oral group.

Fig. 5.

Forest plot of maternal adverse events. M-H: Mantel-Haenszel, CI: confidence interval. *IV group. **Oral group.

Table 1.

Baseline Parameters of the Included Studies

Study	Country	Population	Exclusion criteria	Scheduled group	As-needed group
Li et al., 2025 [21]	China	CS under spinal anesthesia (American Society of Anesthesiologists II-III)	Severe hepatic/renal dysfunction; need for sedatives; mental illness/drug abuse/NSAID allergy; complex CS such as cesarean hysterectomy	300 mg of ibuprofen orally when reported	300 mg ibuprofen orally every 12 h × 48 h starting 6 h post‑delivery; Outcome: FPS‑R pain scale
Yefet et al., 2017 [19]	Israel	CS delivery with regional anesthesia	Chronic pain; chronic analgesic use; drug allergy; GA use; vaginal delivery; abnormal LFTs	Same drug combinations as the demand protocol	IV tramadol 100 mg + paracetamol 500 mg + diclofenac 100 mg initially; scheduled Zaldiar q6h; additional Percocet PRN; Outcome: mean pain intensity over 48 h
Dafna et al., 2019 [20]	Israel	Elective CS (1st/2nd), term, > 18 yr, regional anesthesia	Drug allergy; opioid addiction; > 1 prior CS; emergency CS; BTL; major intra‑op complications	Multimodal VAS-based regimen: paracetamol, dipyrone, ibuprofen	IV paracetamol 1 g tid + ibuprofen bid or oral paracetamol tid + ibuprofen bid; Breakthrough: dipyrone or tramadol 100 mg; Outcome: VAS pain first 48 h

CS: caesarean section, NSAID: nonsteroidal anti-inflammatory drug, GA: general anaesthesia, LFT: liver function test, BTL: bilateral tubal ligation, VAS: visual analogue scale, FPS-R: Faces Pain Scale-Revised, PRN: pro re nata, IV: intravenous.

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