Table 2 Impact of pregnancy risk screening on stillbirth and perinatal mortality

Abraham et al. 1991 [18]

India. Health centre setting.

Prospective cohort study. Health workers at 6 primary health centres used a home-based mothers card with pregnant, mostly illiterate women (N = 2446).

Assessed the association of perinatal mortality with risk factors recorded on a home-based mother's card to pregnant women on which risk factors and ANC attendance were documented.

PMR directly related to # of risk factors:

0 risk factors: PMR = 25.9/1000

1 risk factor: PMR = 39.7/1000

2 risk factors: PMR = 56.5/1000

3 risk factors: PMR 122.5/1000)

Chard et al. 1992 [10]

UK.

N = 994 pregnant women (470 primiparae; 524 multiparae)

Used receiver-operating characteristic curves (ROC) to compare the use of weighted and unweighted risk scores in estimating an overall risk score based on individual risk factors, and relating this score to fetal outcome.

Weighted risk factor method clearly superior to unweighted risk factor method in primiparae.

No difference in multiparae.

Cho et al. 1991 [163]

Korea. Chung Ang Medical Center.

Cross-sectional study to test scoring system. N = 1300 pregnant women (N = 1313 infants) admitted from 1988–1990.

Assessed the utility of Edwards' scoring system adapted to a Korean setting in identifying high-risk pregnancy. Risk scoring included demographic, obstetric, medical, and miscellaneous factors.

560 infants (42.7%) were born to mothers with risk-scores greater than 7, and 753 infants (57.3%) were born to mothers with risk-scores less than 7.

Lefevre et al. 1989 [15]

USA. Rural primary care setting.

Prospective study. N = 635 women. N = 47 (8.3%) adverse outcomes.

Tested the predictive value of Coopland's obstetric risk in anticipating adverse outcome (perinatal death, birthweight < 2500 g, 5-min Apgar score < 7, or newborn transferred to a level 2 or level 3 nursery.

There was a clear relationship between risk score and probability of adverse outcome. Good sensitivity could be achieved only at the expense of a very high false-positive rate, however.

Risk scoring no more effective than a policy that would refer all women with standard obstetric risk factors; majority of adverse outcomes occurred in women identified as low-risk.

Majoko et al. 2002 [12]

Zimbabwe. Rural setting.

Evaluation of screening test; sub-study of ANC trial. N = 5223 women who received traditional care from nurse-midwives in 12 rural health centres (N = 2890 high risk).

Used traditional risk scoring at ANC booking to group women into low- and high-risk groups. High-risk women were encouraged to deliver in facilities.

Complications: 924 (17.7%) of women; 62.4% had had risk markers identified at booking. 20% (577/2890) of women classified as high risk developed complications.

Predictive ability of risk allocation: Likelihood ratio = 1.16.

Mikulandra 1986 [164]

Croatia.

Prospective study.

Assessed the associations of a risk factor scale (low, moderate, and high risk) for pregnancy and delivery on perinatal outcomes.

High pregnancy risk: 10.9% of cases.

High intrapartum risk: 14.02% of cases.

Severe asphyxia (Apgar ≤3): 0.37%, 0.81%, and 4.36% in low, moderate, and high-risk groups, respectively (P < 0.001).

SBR: 0.76% vs. 34.48% in low vs. high-risk groups (P < 0.01)

Morrison 1980 [165]

USA.

Retrospective analysis. N = 1994 consecutive parturients, N = 472 (23%) high-risk (risk score ≥ 3).

Assessed the association of high-risk (risk score ≥ 3) pregnancy with adverse perinatal outcomes.

PMR: Significantly higher in high-risk group (P > 0.001).

Abnormal intrapartum outcome: 71% of high-risk group (P < 0.0001).

Morrison 1979 [11]

USA.

N = 16,733 deliveries. Women scored during pregnancy using a simplified, numerical form for antepartum risk scoring.

Tested the predictive value of a simplified risk scoring system in anticipating the risk of perinatal mortality.

19% of group was high-risk (score ≥ 3).

PMR: 69/1000 vs. 7/1000 in high- vs. low-risk groups, respectively (P < 0.0001).

70% of perinatal deaths occurred in high-risk group.

Talsania et al. 1994 [14]

India (Ahmedabad).

N = 687 indigent women enrolled during first trimester. Women scored as no, mild, moderate, or severe risk based on sociodemographic and obstetric data.

Assessed association of risk factors and risk scoring with perinatal mortality.

PMR: 84.77/1000 births overall; 7.94 in no risk, 92.20/1000 for mild, 200/1000 for severe. Statistically significant.

PMR: OR = 13.09 in women with risk factors vs. women without, respectively.

PM sensitivity, specificity, PPV were 98.31%, 19.90%, and 10.34% respectively.

Talsania et al. 1991 [13]

India (Ahmedabad).

N = 687 women enrolled at < 12 wks gestation, given risk scoring during their first and second visits, during their second and third trimesters, and when admitted for delivery.

Assessed the association of risk factors with perinatal mortality.

81.66% had risk factors. Women with no risk factors had no stillbirths, while 20% of those in the highest risk group did.