Reasons for exclusion of studies after full-text review
| Study reference | Reasons for exclusion |
| Studies from LMICs | |
| Tee et al 15 | This was a descriptive study of the prevalence and outcomes of nutritional anaemia among 309 pregnant women in a maternity hospital in Malaysia. Thus it did not fit the inclusion criteria for study design, interventions and outcomes. |
| Tsu16 | Pregnant women who were induced with oxytocin before delivery were excluded, hence no intervention or comparator. |
| Phillip et al 17 | Pregnant women with anaemia were excluded from the study. |
| Kavle et al 3 | Did not include any information on the intervention of interest—induction and/or augmentation of labour compared with spontaneous vaginal delivery. The study showed that ergometrine and/or oxytocins in the third stage of labour were significantly associated with increased odds of postpartum haemorrhage. |
| Wang et al 18 | This was a case–control study that examined the risk factors for PPH. Anaemia was found to be an independent risk factors for PPH, but management of labour and delivery was not examined. |
| Donchev19 | This study compared the proportions of maternal and fetal complications between 138 pregnant women with anaemia and 300 pregnant women without anaemia. Higher proportions of women with anaemia had preterm delivery, prolonged labour, uterine inertia and birth asphyxia compared with women with no anaemia. The study did not fit the inclusion criterion for interventions. |
| Studies from HICs | |
| Salwa20 | This study examined complications during labour and delivery in 309 pregnant women and reported a higher prevalence of PPH in women with anaemia (11%–75%) compared with women with no anaemia (8.2%). The study did not fit the inclusion criterion for interventions. |
| Daraz21 | This cross-sectional study of 2128 pregnant women during labour showed that the average duration of the first and second stages of labour increased with a decrease in the concentration of haemoglobin, but the association was statistically significant for multiparous women only. The study did not fit the inclusion criteria for study design, interventions and outcomes. |
LMICs, low and middle-income countries; HICs, high-income countries; PPH, postpartum haemorrhage