Simbar 2015.

Study characteristics
Methods	Randomised controlled trial
Participants	Setting: Alzahra Hospital, Tehran, Iran. From April 2011 to February 2012 Inclusion criteria: primi‐ or multiparous women with moderate‐to‐severe after‐pain (score > 4 on VAS and with need for analgesia), normal vaginal delivery Exclusion criteria: women with birth complicated by perineal laceration, prolonged labour, macrosomia, instrumental birth, analgesics in previous 2 weeks
Interventions	Following initial assessment of pain, women were randomly allocated to 1 of 2 groups: Experimental intervention: pimpinella anisum, apium graveolens and crocus sativus (PAC), (500 mg capsule, provided as Menstrogol), 1st capsule within 2 hours of birth, then up to 4 doses 6‐hourly for 24 hours (N = 54) Control/comparison: mefenamic acid (250 mg capsules), 1st capsule within 2 hours of birth, then up to 4 doses 6‐hourly for 24 hours. (N = 54)
Outcomes	Adequate pain relief as reported by the women Severity of after‐pains on VAS (scale 0 ‐ 10, no pain to very severe pain) 1. Before Intervention; 2. 1 hour after intervention. Pain intensity difference following the 1st dose was calculated and used to estimate 'adequate pain relief as assessed by the woman' (estimate over 1 hour) Pain however reported by the authors: Time until pain relief experienced (duration of pain) Maternal side effects: side effects of intervention.
Notes	Funding sources: Goldaru Company ‐ manufacturer of Menstrogol Declarations of interests: the authors declare that they have no conflicts of interest
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No information related to sequence generation
Allocation concealment (selection bias)	Unclear risk	Quote: "participants randomly selected a packet that was coded A or B containing 4 capsules of PAC of MAC". Unclear if codes visible
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Single‐blind, assume participants were blinded but personnel may not have been blinded
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Trial registration states that study is double‐blind but publication states single‐blind. Therefore unclear if they were excluded if they experienced any side effects or requested to withdraw from the study. Unclear how many participants applied to withdraw
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	The trial included 108 women, 54 in each group. Pain severity before and after treatment does not include the number of women. Latency for medication effect reports data from 54 women in each group. Study report states that "participants were excluded if they experienced any side effects or requested to withdraw from the study". Unclear how many participants this applied to
Selective reporting (reporting bias)	High risk	Trial registered retrospectively
Other bias	Low risk	No other risk of bias identified