Postpartum haemorrhage in rural Indigenous women: scoping review of a global obstetrical challenge

Figures & data

Table 1. Search strategies.

Database	Search Strategy
MEDLINE (via PubMed)	(“Postpartum Hemorrhage”[Mesh] OR “postpartum hemorrhage”[tw] OR “postpartum haemorrhage”[tw] OR “post partum hemorrhage”[tw] OR “post partum haemorrhage”[tw] OR pph[tw] OR “uterine atony”[tw] OR “retained placenta”[tw] OR “retained products of conception”[tw] OR “retained placenta”[tw] OR coagulopathy[tw] OR “Perineum/injuries”[Mesh] OR “Vagina/injuries”[Mesh] OR “Cervix Uteri/injuries”[Mesh] OR ((vaginal[tw] OR perineal[tw] OR cervical[tw]) AND (trauma[tw] OR laceration*[tw] OR tear*[tw]))) AND (“Health Services, Indigenous”[Mesh] OR “Indians, North American”[Mesh] OR “Inuits”[Mesh] OR “Oceanic Ancestry Group”[Mesh] OR inuit*[tw] OR eskimo*[tw] OR “first nations”[tw] OR “native american*”[tw] OR “native hawaiian*”[tw] OR “native alaskan*”[tw] OR “alaska native*”[tw] OR “alaskan native*”[tw] OR “pacific islander*”[tw] OR “american indian*”[tw] OR aborigin*[tw] OR indigenous[tw] OR “Rural Health”[Mesh] OR “Rural Health Services”[Mesh:NoExp] OR “Rural Population”[Mesh] OR “Hospitals, Rural”[Mesh] OR rural[tw] OR “remote area*”[tw] OR “remote region*”[tw] OR “remote communit*”[tw] OR “remote clinic*”[tw])
CINAHL (via EBSCOhost)	(MH “Postpartum Hemorrhage” OR “postpartum hemorrhage” OR “postpartum haemorrhage” OR “post partum hemorrhage” OR “post partum haemorrhage” OR PPH OR MH “Uterine Inertia” OR “uterine antony” OR “retained placenta” OR “retained products of conception” OR coagulopathy OR MH “Vagina/IN” OR MH “Perineal/IN” OR MH “Cervix/IN” OR ((TI vaginal OR AB vaginal OR TI perineal OR AB perineal OR TI cervical OR AB cervical) AND (TI trauma OR AB trauma OR TI laceration* OR AB laceration* OR TI tear* OR AB tear*))) AND (MH “Health Services, Indigenous” OR MH “Indigenous Health” OR MH “Indigenous Peoples” OR MH “Aborigines” OR MH “Maori” OR MH “Eskimos” OR MH “Native Americans” OR TI inuit* OR AB inuit* OR TI eskimo* OR AB eskimo* OR TI “first nations” OR AB “first nations” OR TI “native american*” OR AB “native american*” OR TI “native hawaiian*” OR AB “native hawaiian*” OR TI “native alaskan*” OR AB “native alaskan*” OR TI “alaska native*” OR AB “alaska native*” OR TI “alaskan native*” OR AB “alaskan native*” OR TI “pacific islander*” OR AB “pacific islander*” OR TI “american indian*” OR AB “american indian*” OR TI aborigin* OR AB aborigin* OR TI indigenous OR AB indigenous OR MH “Rural Health Personnel” OR MH “Rural Health Centers” OR MH “Hospitals, Rural” OR MH “Rural Population” OR MH “Rural Health Services” OR MH “Rural Health Nursing” OR MH “Rural Areas” OR MH “Rural Health” OR MH “Frontier Nursing Service” OR TI rural OR AB rural OR (remote N2 (area* OR communit* OR region* OR clinic*)))
EMBASE (via embase.com)	(“postpartum hemorrhage”/de OR “postpartum hemorrhage”:ab,ti OR “postpartum haemorrhage”:ab,ti OR “post partum hemorrhage”:ab,ti OR “post partum haemorrhage”:ab,ti OR pph:ab,ti OR “uterine atony”/de OR “uterine atony”:ab,ti OR “retained placenta”:ab,ti OR “retained products of conception”:ab,ti OR coagulopathy:ab,ti OR “perineum injury”/de OR “vaginal injury”/de OR ((vaginal:ab,ti OR perineal:ab,ti OR cervical:ab,ti) AND (trauma:ab,ti OR laceration*:ab,ti OR tear*:ab,ti))) AND (“indigenous health care”/de OR “indigenous people”/exp OR inuit*:ab,ti OR eskimo*:ab,ti OR “first nations”:ab,ti OR “native american*”:ab,ti OR “native hawaiian*”:ab,ti OR “native alaskan*”:ab,ti OR “alaska native*”:ab,ti OR “alaskan native*”:ab,ti OR “pacific islander*”:ab,ti OR “american indian*”:ab,ti OR aborigin*:ab,ti OR indigenous:ab,ti OR “rural health care”/de OR “rural health nursing”/de OR “rural population”/de OR “rural area”/de OR “rural health”/de OR (remote NEAR/2 (area* OR communit* OR region* OR clinic*)))

All searches conducted 11 January 2021. No date or language limiters were applied.

Table 2. Inclusion criteria and their operational definitions.

Inclusion Criteria	Operational Definitions
Population	Indigenous: As defined by the World Health Organization, indigenous people are as those that live in distinct geographical territories, identify themselves as belonging to a cultural group separate from mainstream society and descended from groups present in the area before modern states and borders.^22 For practical purposes, a population or patient was considered aboriginal if the study defined them as: Aboriginal; Indigenous; Inuit; Métis, First Nations, Native American; American Indian; Australian Aboriginal or; Torres Strait Islander.
Setting	Rural or Remote Settings: For practical purposes, a population was considered rural and remote if 1) the study labelled the population as rural or remote, 2) the population is considered far from a tertiary care centre or 3) the population was not-urban – living outside of a city of 10,000 or more people.
Outcome	If any of the following outcomes were assessed: PPH incidence, risk factors of incidence and maternal outcomes: PPH: Blood loss of 500cc or more from the maternal reproductive tract following delivery up to 6 weeks postpartum (WHO, SOGC). PPH was identified if 1) the estimated blood loss (EBL) was ≥ 500cc or 2) the study labelled a case a PPH. If there was a discrepancy between a study’s reported incidence of PPH and EBL ≥ 500cc, the incidence of PPH was recorded using the study’s reported incidence.

Table 2 shows the inclusion criteria for the systematic library search and associated operational definitions.

Figure 1. PRISMA diagram of search decision strategy.

Table 3. Characteristics of included studies.

Country	Study, Year	Region	Circumpolar Region	Published	Study Design	Data source	Population	Comparison Groups	Population			Outcome Assessed			Quality
									Rural-Dwelling	Rural Delivery	Sample Size	Incidence	Maternal Outcomes	Risk Factors
Australia	Kildea 2016	Northern Queensland		Y	Ambi-directional cohort	Medical records	Remote-dwelling Aboriginal women with deliveries > 20 weeks or 400 g	New model of care vs. old model of care	100%	10%	695 deliveries	Y			Good
	Humphrey 2003	Northern Queensland		Y	Retrospective cohort	Medical records	Women with singleton deliveries	Indigenous women vs. non-Indigenous women	80%*	0%	4823 aboriginal women			Y	Fair
Canada	Tarlier 2013	Unspecified		Y	Retrospective Cohort/ Ethnographic	Medical records	Women with deliveries over 2 years	First Nations women with deliveries vs. Optimal health outcomes in maternal and infant health	100%	No data	63 deliveries	Y	Y		Poor
	Van Wagner 2012	Nunavik (Northern Quebec)	Y	Y	Retrospective cohort	Medical records	Women with deliveries between 2000 and 2007 from Hudson Coast of Nunavik	None	100%	86.60%	1168 deliveries	Y	Y		Poor
	Carignan 1993	Nunavik (Northern Quebec)	Y		Hybrid (cohort and cross-sectional	Medical records & Questionnaire	Women with deliveries in 1989 from Hudson Coast of Nunavik delivering	None	100%	84.80%	347 deliveries	Y	Y		Poor
	Murdoch 1979	Nunavut	Y	Y	Retrospective cohort	Medical records	Inuit women with deliveries in 1 region over 23 months and in a 2nd region over 12 months	Risk factors for Baffin zoned women between 1976–1977	100%	88.20%	414 deliveries	Y			Poor
	Basket 1978	Nunavut	Y	Y	Retrospective cohort	Medical records	Inuit women with deliveries	Keewatin Inuit women vs. North-West Territories Inuit Women vs. Canadian Women	100%	89.30%	622 deliveries	Y	Y		Poor
	Thomas 1968	British Columbia		Y	Case series	Vital statistics/ medical records	Maternal deaths among native BC Indians from 1955–1965	Indian women vs. non-Indian women	Unspecified	Unspecified	26 maternal deaths		Y	Y	Poor
	Carpenter 1965	British Columbia		Y	Case Series	Provincial vital statistics	Maternal deaths from 1955–1962	Native Indian women vs. Population at large	Unspecified	Unspecified	145 maternal deaths		Y	Y	Poor
USA	Chalouhi, 2015	New Mexico		Y	Retrospective cohort	Medical records	Women with singleton term deliveries	Native American women vs. non-Native American women (Hispanic, White, Middle Eastern, Asian, Black)	Unspecified	Unclear – Hospital in Galluq (population 20,000)	1062 women	Y	Y	Y	Good
	Fenton, 2005	Southwest		Y	Retrospective cohort	Medical records	Rural American Indian women with deliveries	American Indian women who received AMTSL vs. American Indian women who received routine management of the third stage of labour	100%	100%	176 women	Y	Y	Y	Good

Y:Yes; Blank:No

Table 4. Results of quality appraisal.

Table 5. Definition and incidence of PPH derived from the identified studies.

Country	Study	Definition of PPH	Definition of Severe PPH	Sample Size	PPH Incidence by Study Definition(%)	PPH Incidence by EBL ≥500 mL (%)	Severe PPH Incidence (%)	Definition of AMTSL	Use of AMTSL
Australia	Kildea 2016	EBL ≥ 500 ml	EBL ≥ 1500 ml	695 deliveries,^†	n = 208 (29 · 90%)^‡	n = 208 (29.90%)	n = 14 (2.0%)	-	-
	Humphrey 2003	EBL > 500 mL	-	4683 aboriginal women	-	-	-	-	-
Canada	Tarlier 2013	-	-	63 deliveries	n = 5 (7 · 9%)	-	-	-	-
	Van Wagner 2012	Provider diagnosis	-	1168 deliveries	n = 221 (15.40%)	n = 438 (37.50%	-	-	49.8%
	Carignan 1993	Provider diagnosis	-	347 deliveries	n = 38 (14.20%)	n = 137 (39.50%)	-	-	-
	Murdoch 1979	EBL > 500 mL	-	414 deliveries	n = 24 (5 · 8%)	n = 38 (5.8%)	-	-	-
	Basket 1978	Provider diagnosis	-	622 deliveries,	n = 63 (10.1%)	-	-	-	-
USA	Chalouhi 2015	EBL > 500 mL	-	751 women	n = 87 (11.6%)	n = 87 (11.6%)	-	-	-
	Fenton 2005	3 g/dl postpartum Hb decline	-	148 women^§	n = 27 (18.20%)	n = 36 (24.30%)	-	Oxytocin given immediately after delivery of anterior shoulder	35.40%

Table 5 provides an overview of all 11 studies included in the scoping review. “†” indicates the full sample size for this study was 722, however data on PPH was only available for 695 women. “‡” symbol indicates an aggregate incidence of PPH combining 2 cohorts. “§” indicates the full sample size for this study was 175 women, however, no data was available for 27 women.

Table 6. Summary of PPH risk factors derived from the identified studies.

Country	Study	Risk Factor			Specific Risk Factors Studied
		Pre-Pregnancy	Antepartum	Intrapartum
Australia	Humphrey 2003	Y			Pre-pregnancy risk factor: Indigenous ethnicity significant (OR 1 · 83 p < 0.001) †
Canada	Thomas 1968	Y			Pre-pregnancy risk factor: High incidence of maternal death due to PPH indirectly suggests indigenous ethnicity as a risk factor
	Carpenter 1965	Y			Pre-pregnancy risk factor: Disproportionately high incidence of maternal death due to PPH in Native Indians indirectly suggests indigenous ethnicity as a risk factor
USA	Chalouhi, 2015	Y	Y	Y	Native American ethnicity OR 1 · 8 (1 · 3–3 · 0, p = 0 · 02). Other factors studied in a 70.7% indigenous population: gravity <5 OR 1.2 (p = 0.008), birth weight <4500 g OR = 1.0 (p = 0.001), retained placenta OR 51.0 (p = 0.001), magnesium sulphate usage OR 3.5 (p = 0.0009) were significant risk factors. Maternal age < 35, parity < 5, labour induction or augmentation, and chorioamnionitis were not significant risk factors.
	Fenton, 2005			Y	Protective factor: AMTSL significantly reduced > 3 g/dl decrease in Hb (aOR 0.13, p < 0.001), the decrease in Hb (p = 0.001) and reduced EBL (p = 0.02) vs. routine care. There was no significant effect on EBL ≥500 ml (p = 0.28) or transfusion (p = 0.55)

Y: Yes; Blank: No; †: source article did not provide an exact p-value.

List of risk factors examined for: Pre-pregnancy: maternal age, ethnicity, weight/body mass index, gravida, parity, prior C-section, prior PPH,

prior hypertensive disorder of pregnancy, prior curettage; Antepartum: poor prenatal care, smoking, hypertensive disease of pregnancy, gestation diabetes,

antenatal haemorrhage, anaemia, uterine fibroids, polyhydramnios, multiple gestation; Intrapartum: gestational age at delivery, induction of labour, mode of delivery, prolonged labour, precipitate labour, stillbirth, birth weight, retained placenta, maternal reproductive tract trauma, active management of third stage of labour, magnesium sulphate, chorioamnionitis.

Table 7. Summary of PPH-related outcomes derived from the identified studies.

Country	Study	Tranfusion	Hysterectomy	Mortality
Australia	Humphrey 2003	OR 2.62 (p < 0.001)
Canada	Tarlier 2013		n = 5 (20.0%)
	Van Wagner 2012	n = 15 (7.1%)
	Carignan 1993	n = 8 (21.2%)		n = 0 (0.0%)
	Basket 1978	N = 23 (36.5%)		n = 0 (0.0%)
	Thomas 1968			Indigenous women over-represented in maternal deaths from PPH vs. general population
USA	Chalouhi 2015	n = 30 (34.4%)
	Fenton 2005	n = 3 (11.1%)		n = 0 (0.0%)

Y: Yes; Blank: No

Reported outcomes included mortality, transfusion and hysterectomy. Possible outcomes that were not reported were renal failure, acute respiratory failure, sepsis, prolonged mechanical ventilation, coagulopathy, myocardial infarct, and amniotic fluid embolism.