Scolaris Content Display Scolaris Content Display

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 1 Pregnancy induced hypertension.
Figures and Tables -
Analysis 1.1

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 1 Pregnancy induced hypertension.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 2 Proteinuric pre‐eclampsia.
Figures and Tables -
Analysis 1.2

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 2 Proteinuric pre‐eclampsia.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 3 Eclampsia.
Figures and Tables -
Analysis 1.3

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 3 Eclampsia.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 4 Maternal death.
Figures and Tables -
Analysis 1.4

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 4 Maternal death.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 5 Placental abruption.
Figures and Tables -
Analysis 1.5

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 5 Placental abruption.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 6 Caesarean section.
Figures and Tables -
Analysis 1.6

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 6 Caesarean section.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 7 Induction of labour.
Figures and Tables -
Analysis 1.7

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 7 Induction of labour.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 8 Hospital admission for the woman during pregnancy.
Figures and Tables -
Analysis 1.8

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 8 Hospital admission for the woman during pregnancy.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 9 Preterm birth (< 37 weeks).
Figures and Tables -
Analysis 1.9

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 9 Preterm birth (< 37 weeks).

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 10 Preterm birth (subgroups by gestational age).
Figures and Tables -
Analysis 1.10

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 10 Preterm birth (subgroups by gestational age).

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 11 Fetal and neonatal deaths.
Figures and Tables -
Analysis 1.11

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 11 Fetal and neonatal deaths.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 12 Fetal, neonatal, infant and childhood deaths (subgroups by time of death).
Figures and Tables -
Analysis 1.12

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 12 Fetal, neonatal, infant and childhood deaths (subgroups by time of death).

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 13 Deaths after discharge from hospital.
Figures and Tables -
Analysis 1.13

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 13 Deaths after discharge from hospital.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 14 Small for gestational age (any definition).
Figures and Tables -
Analysis 1.14

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 14 Small for gestational age (any definition).

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 15 Small for gestational age (subgroups by severity).
Figures and Tables -
Analysis 1.15

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 15 Small for gestational age (subgroups by severity).

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 16 Birthweight < 2500g.
Figures and Tables -
Analysis 1.16

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 16 Birthweight < 2500g.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 17 Admission to a special care baby unit.
Figures and Tables -
Analysis 1.17

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 17 Admission to a special care baby unit.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 18 Intraventricular haemorrhage.
Figures and Tables -
Analysis 1.18

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 18 Intraventricular haemorrhage.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 19 Other neonatal bleed.
Figures and Tables -
Analysis 1.19

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 19 Other neonatal bleed.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 20 Non‐routine GP consultation for child.
Figures and Tables -
Analysis 1.20

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 20 Non‐routine GP consultation for child.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 21 Child admitted to hospital.
Figures and Tables -
Analysis 1.21

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 21 Child admitted to hospital.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 22 Developmental problems at 18 months.
Figures and Tables -
Analysis 1.22

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 22 Developmental problems at 18 months.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 23 Behaviour problems at 18 months.
Figures and Tables -
Analysis 1.23

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 23 Behaviour problems at 18 months.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 24 Malformations at 18 months.
Figures and Tables -
Analysis 1.24

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 24 Malformations at 18 months.

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 25 Growth at 18 months.
Figures and Tables -
Analysis 1.25

Comparison 1 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk), Outcome 25 Growth at 18 months.

Comparison 2 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry), Outcome 1 Pregnancy induced hypertension.
Figures and Tables -
Analysis 2.1

Comparison 2 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry), Outcome 1 Pregnancy induced hypertension.

Comparison 2 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry), Outcome 2 Proteinuric pre‐eclampsia.
Figures and Tables -
Analysis 2.2

Comparison 2 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry), Outcome 2 Proteinuric pre‐eclampsia.

Comparison 2 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry), Outcome 3 Placental abruption.
Figures and Tables -
Analysis 2.3

Comparison 2 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry), Outcome 3 Placental abruption.

Comparison 2 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry), Outcome 4 Preterm birth.
Figures and Tables -
Analysis 2.4

Comparison 2 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry), Outcome 4 Preterm birth.

Comparison 2 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry), Outcome 5 Fetal, neonatal or infant death.
Figures and Tables -
Analysis 2.5

Comparison 2 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry), Outcome 5 Fetal, neonatal or infant death.

Comparison 2 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry), Outcome 6 Small‐for‐gestational age.
Figures and Tables -
Analysis 2.6

Comparison 2 Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry), Outcome 6 Small‐for‐gestational age.

Comparison 3 Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo), Outcome 1 Pregnancy induced hypertension.
Figures and Tables -
Analysis 3.1

Comparison 3 Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo), Outcome 1 Pregnancy induced hypertension.

Comparison 3 Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo), Outcome 2 Proteinuric pre‐eclampsia.
Figures and Tables -
Analysis 3.2

Comparison 3 Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo), Outcome 2 Proteinuric pre‐eclampsia.

Comparison 3 Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo), Outcome 3 Placental abruption.
Figures and Tables -
Analysis 3.3

Comparison 3 Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo), Outcome 3 Placental abruption.

Comparison 3 Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo), Outcome 4 Preterm birth.
Figures and Tables -
Analysis 3.4

Comparison 3 Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo), Outcome 4 Preterm birth.

Comparison 3 Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo), Outcome 5 Fetal, neonatal or infant death.
Figures and Tables -
Analysis 3.5

Comparison 3 Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo), Outcome 5 Fetal, neonatal or infant death.

Comparison 3 Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo), Outcome 6 Small‐for‐gestational age.
Figures and Tables -
Analysis 3.6

Comparison 3 Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo), Outcome 6 Small‐for‐gestational age.

Comparison 4 Aspirin versus placebo/no treatment (subgrouped by dose), Outcome 1 Pregnancy induced hypertension.
Figures and Tables -
Analysis 4.1

Comparison 4 Aspirin versus placebo/no treatment (subgrouped by dose), Outcome 1 Pregnancy induced hypertension.

Comparison 4 Aspirin versus placebo/no treatment (subgrouped by dose), Outcome 2 Proteinuric pre‐eclampsia.
Figures and Tables -
Analysis 4.2

Comparison 4 Aspirin versus placebo/no treatment (subgrouped by dose), Outcome 2 Proteinuric pre‐eclampsia.

Comparison 4 Aspirin versus placebo/no treatment (subgrouped by dose), Outcome 3 Placental abruption.
Figures and Tables -
Analysis 4.3

Comparison 4 Aspirin versus placebo/no treatment (subgrouped by dose), Outcome 3 Placental abruption.

Comparison 4 Aspirin versus placebo/no treatment (subgrouped by dose), Outcome 4 Preterm birth.
Figures and Tables -
Analysis 4.4

Comparison 4 Aspirin versus placebo/no treatment (subgrouped by dose), Outcome 4 Preterm birth.

Comparison 4 Aspirin versus placebo/no treatment (subgrouped by dose), Outcome 5 Fetal, neonatal or infant death.
Figures and Tables -
Analysis 4.5

Comparison 4 Aspirin versus placebo/no treatment (subgrouped by dose), Outcome 5 Fetal, neonatal or infant death.

Comparison 4 Aspirin versus placebo/no treatment (subgrouped by dose), Outcome 6 Small‐for‐gestational age.
Figures and Tables -
Analysis 4.6

Comparison 4 Aspirin versus placebo/no treatment (subgrouped by dose), Outcome 6 Small‐for‐gestational age.

Comparison 5 Antiplatelet agent + other agents versus placebo/no treatment (subgrouped by type of agent), Outcome 1 Proteinuric pre‐eclampsia.
Figures and Tables -
Analysis 5.1

Comparison 5 Antiplatelet agent + other agents versus placebo/no treatment (subgrouped by type of agent), Outcome 1 Proteinuric pre‐eclampsia.

Comparison 5 Antiplatelet agent + other agents versus placebo/no treatment (subgrouped by type of agent), Outcome 2 Fetal or neonatal death.
Figures and Tables -
Analysis 5.2

Comparison 5 Antiplatelet agent + other agents versus placebo/no treatment (subgrouped by type of agent), Outcome 2 Fetal or neonatal death.

Comparison 1. Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk)

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Pregnancy induced hypertension Show forest plot

31

21754

Risk Ratio (M‐H, Fixed, 95% CI)

0.98 [0.90, 1.06]

1.1 moderate‐risk women

22

21107

Risk Ratio (M‐H, Fixed, 95% CI)

1.01 [0.93, 1.09]

1.2 high‐risk women

9

647

Risk Ratio (M‐H, Fixed, 95% CI)

0.60 [0.44, 0.83]

2 Proteinuric pre‐eclampsia Show forest plot

43

33439

Risk Ratio (M‐H, Fixed, 95% CI)

0.81 [0.75, 0.88]

2.1 moderate‐risk women

24

29217

Risk Ratio (M‐H, Fixed, 95% CI)

0.85 [0.77, 0.94]

2.2 high‐risk women

19

4222

Risk Ratio (M‐H, Fixed, 95% CI)

0.73 [0.64, 0.83]

3 Eclampsia Show forest plot

12

14977

Risk Ratio (M‐H, Fixed, 95% CI)

0.85 [0.53, 1.38]

4 Maternal death Show forest plot

3

12709

Risk Ratio (M‐H, Fixed, 95% CI)

2.57 [0.39, 17.06]

5 Placental abruption Show forest plot

16

25806

Risk Ratio (M‐H, Fixed, 95% CI)

1.06 [0.85, 1.32]

5.1 moderate‐risk women

12

23066

Risk Ratio (M‐H, Fixed, 95% CI)

1.13 [0.89, 1.44]

5.2 high‐risk women

4

2740

Risk Ratio (M‐H, Fixed, 95% CI)

0.72 [0.40, 1.29]

6 Caesarean section Show forest plot

23

29406

Risk Ratio (M‐H, Fixed, 95% CI)

1.02 [0.98, 1.06]

7 Induction of labour Show forest plot

5

19295

Risk Ratio (M‐H, Fixed, 95% CI)

1.03 [0.98, 1.08]

8 Hospital admission for the woman during pregnancy Show forest plot

2

9323

Risk Ratio (M‐H, Fixed, 95% CI)

1.05 [0.97, 1.14]

9 Preterm birth (< 37 weeks) Show forest plot

28

31845

Risk Ratio (M‐H, Fixed, 95% CI)

0.93 [0.89, 0.98]

9.1 moderate‐risk women

19

28693

Risk Ratio (M‐H, Fixed, 95% CI)

0.94 [0.89, 0.99]

9.2 high‐risk women

9

3152

Risk Ratio (M‐H, Fixed, 95% CI)

0.90 [0.83, 0.99]

10 Preterm birth (subgroups by gestational age) Show forest plot

25

Risk Ratio (M‐H, Fixed, 95% CI)

Subtotals only

10.1 delivery < 37 completed weeks

24

31522

Risk Ratio (M‐H, Fixed, 95% CI)

0.93 [0.89, 0.98]

10.2 delivery < 34 completed weeks

5

5248

Risk Ratio (M‐H, Fixed, 95% CI)

0.87 [0.64, 1.20]

10.3 delivery < 32 completed weeks

7

15180

Risk Ratio (M‐H, Fixed, 95% CI)

0.96 [0.80, 1.15]

11 Fetal and neonatal deaths Show forest plot

38

34010

Risk Ratio (M‐H, Fixed, 95% CI)

0.84 [0.74, 0.96]

11.1 moderate‐risk women

21

29364

Risk Ratio (M‐H, Fixed, 95% CI)

0.91 [0.78, 1.06]

11.2 high‐risk women

17

4646

Risk Ratio (M‐H, Fixed, 95% CI)

0.68 [0.53, 0.87]

12 Fetal, neonatal, infant and childhood deaths (subgroups by time of death) Show forest plot

34

Risk Ratio (M‐H, Fixed, 95% CI)

Subtotals only

12.1 stillbirths

27

18892

Risk Ratio (M‐H, Fixed, 95% CI)

0.97 [0.78, 1.20]

12.2 perinatal deaths

15

16028

Risk Ratio (M‐H, Fixed, 95% CI)

0.89 [0.73, 1.09]

12.3 neonatal deaths

20

12968

Risk Ratio (M‐H, Fixed, 95% CI)

0.83 [0.61, 1.14]

13 Deaths after discharge from hospital Show forest plot

2

5886

Risk Ratio (M‐H, Fixed, 95% CI)

0.53 [0.21, 1.34]

13.1 deaths 8 days to 18 months

1

788

Risk Ratio (M‐H, Fixed, 95% CI)

1.69 [0.15, 18.57]

13.2 hospital discharge ‐ 12 months

1

4688

Risk Ratio (M‐H, Fixed, 95% CI)

0.28 [0.08, 0.99]

13.3 hospital discharge ‐ 18 months

1

410

Risk Ratio (M‐H, Fixed, 95% CI)

2.16 [0.20, 23.66]

14 Small for gestational age (any definition) Show forest plot

32

24310

Risk Ratio (M‐H, Fixed, 95% CI)

0.92 [0.85, 1.00]

14.1 moderate‐risk women

20

20111

Risk Ratio (M‐H, Fixed, 95% CI)

0.93 [0.85, 1.02]

14.2 high‐risk women

12

4199

Risk Ratio (M‐H, Fixed, 95% CI)

0.90 [0.75, 1.09]

15 Small for gestational age (subgroups by severity) Show forest plot

26

25005

Risk Ratio (M‐H, Fixed, 95% CI)

0.93 [0.86, 1.01]

15.1 birthweight < 10th centile

14

8905

Risk Ratio (M‐H, Fixed, 95% CI)

0.92 [0.82, 1.04]

15.2 birthweight < 5th centile

3

1390

Risk Ratio (M‐H, Fixed, 95% CI)

1.06 [0.77, 1.44]

15.3 birthweight < 3rd centile

7

12938

Risk Ratio (M‐H, Fixed, 95% CI)

0.93 [0.81, 1.07]

15.4 definition not stated

4

1772

Risk Ratio (M‐H, Fixed, 95% CI)

0.93 [0.68, 1.27]

16 Birthweight < 2500g Show forest plot

6

7577

Risk Ratio (M‐H, Fixed, 95% CI)

0.91 [0.82, 1.02]

17 Admission to a special care baby unit Show forest plot

15

29092

Risk Ratio (M‐H, Fixed, 95% CI)

0.96 [0.91, 1.02]

18 Intraventricular haemorrhage Show forest plot

10

26184

Risk Ratio (M‐H, Fixed, 95% CI)

0.88 [0.63, 1.22]

19 Other neonatal bleed Show forest plot

7

26896

Risk Ratio (M‐H, Fixed, 95% CI)

1.13 [0.83, 1.52]

20 Non‐routine GP consultation for child Show forest plot

1

Risk Ratio (M‐H, Fixed, 95% CI)

Subtotals only

20.1 at 12 months

1

4168

Risk Ratio (M‐H, Fixed, 95% CI)

1.00 [0.99, 1.02]

20.2 at 18 months

1

4365

Risk Ratio (M‐H, Fixed, 95% CI)

1.00 [0.96, 1.04]

21 Child admitted to hospital Show forest plot

1

Risk Ratio (M‐H, Fixed, 95% CI)

Subtotals only

21.1 at 12 months

1

4168

Risk Ratio (M‐H, Fixed, 95% CI)

0.94 [0.83, 1.08]

21.2 at 18 months

1

4365

Risk Ratio (M‐H, Fixed, 95% CI)

0.99 [0.89, 1.11]

22 Developmental problems at 18 months Show forest plot

2

Risk Ratio (M‐H, Fixed, 95% CI)

Subtotals only

22.1 poor gross motor function

1

4365

Risk Ratio (M‐H, Fixed, 95% CI)

0.82 [0.57, 1.17]

22.2 poor fine motor function

1

4365

Risk Ratio (M‐H, Fixed, 95% CI)

0.98 [0.84, 1.14]

22.3 poor gross or fine motor function

1

788

Risk Ratio (M‐H, Fixed, 95% CI)

0.49 [0.26, 0.91]

22.4 respiratory problems

1

788

Risk Ratio (M‐H, Fixed, 95% CI)

1.48 [0.98, 2.23]

22.5 poor language expression

1

4365

Risk Ratio (M‐H, Fixed, 95% CI)

0.94 [0.74, 1.19]

22.6 poor language comprehension

1

4365

Risk Ratio (M‐H, Fixed, 95% CI)

0.95 [0.80, 1.13]

22.7 language problems ‐ undefined

1

788

Risk Ratio (M‐H, Fixed, 95% CI)

0.99 [0.69, 1.42]

22.8 hearing problems

1

788

Risk Ratio (M‐H, Fixed, 95% CI)

2.54 [0.10, 62.10]

22.9 sight problems

1

788

Risk Ratio (M‐H, Fixed, 95% CI)

0.85 [0.25, 2.90]

23 Behaviour problems at 18 months Show forest plot

1

4365

Risk Ratio (M‐H, Fixed, 95% CI)

0.87 [0.75, 1.01]

23.1 poor sleep pattern

1

4365

Risk Ratio (M‐H, Fixed, 95% CI)

0.87 [0.75, 1.01]

24 Malformations at 18 months Show forest plot

1

788

Risk Ratio (M‐H, Fixed, 95% CI)

0.74 [0.27, 2.02]

25 Growth at 18 months Show forest plot

2

10306

Risk Ratio (M‐H, Fixed, 95% CI)

0.94 [0.84, 1.07]

25.1 height < 3rd or 10th centile

2

5153

Risk Ratio (M‐H, Fixed, 95% CI)

0.94 [0.80, 1.09]

25.2 weight < 3rd or 10th centile

2

5153

Risk Ratio (M‐H, Fixed, 95% CI)

0.96 [0.79, 1.16]

Figures and Tables -
Comparison 1. Antiplatelet agents versus placebo/no antiplatelet (subgrouped by maternal risk)
Comparison 2. Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry)

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Pregnancy induced hypertension Show forest plot

31

21754

Risk Ratio (M‐H, Fixed, 95% CI)

0.98 [0.90, 1.06]

1.1 entered into the study < 20 weeks

13

7787

Risk Ratio (M‐H, Fixed, 95% CI)

0.95 [0.84, 1.07]

1.2 entered into the study > 20 weeks

12

3886

Risk Ratio (M‐H, Fixed, 95% CI)

0.88 [0.74, 1.06]

1.3 unclassified

7

10081

Risk Ratio (M‐H, Fixed, 95% CI)

1.06 [0.93, 1.20]

2 Proteinuric pre‐eclampsia Show forest plot

43

33439

Risk Ratio (M‐H, Fixed, 95% CI)

0.81 [0.75, 0.88]

2.1 entered into the study < 20 weeks

20

17455

Risk Ratio (M‐H, Fixed, 95% CI)

0.85 [0.76, 0.94]

2.2 entered into the study > 20weeks

21

10263

Risk Ratio (M‐H, Fixed, 95% CI)

0.80 [0.70, 0.91]

2.3 unclassified

7

5721

Risk Ratio (M‐H, Fixed, 95% CI)

0.71 [0.56, 0.89]

3 Placental abruption Show forest plot

16

25806

Risk Ratio (M‐H, Fixed, 95% CI)

1.06 [0.85, 1.32]

3.1 entered into study at < 20 weeks

5

3735

Risk Ratio (M‐H, Fixed, 95% CI)

1.11 [0.60, 2.05]

3.2 entered into study at > 20 weeks

4

290

Risk Ratio (M‐H, Fixed, 95% CI)

1.19 [0.37, 3.81]

3.3 unclassified

7

21781

Risk Ratio (M‐H, Fixed, 95% CI)

1.05 [0.82, 1.33]

4 Preterm birth Show forest plot

28

31845

Risk Ratio (M‐H, Fixed, 95% CI)

0.93 [0.89, 0.97]

4.1 entered into the study < 20 weeks

14

16644

Risk Ratio (M‐H, Fixed, 95% CI)

0.94 [0.88, 1.01]

4.2 entered into the study > 20 weeks

15

9708

Risk Ratio (M‐H, Fixed, 95% CI)

0.89 [0.82, 0.96]

4.3 unclassified

4

5493

Risk Ratio (M‐H, Fixed, 95% CI)

1.01 [0.88, 1.15]

5 Fetal, neonatal or infant death Show forest plot

38

34010

Risk Ratio (M‐H, Fixed, 95% CI)

0.85 [0.75, 0.97]

5.1 entered into the study < 20 weeks

16

17501

Risk Ratio (M‐H, Fixed, 95% CI)

0.83 [0.69, 0.99]

5.2 entered into the study > 20 weeks

21

10857

Risk Ratio (M‐H, Fixed, 95% CI)

0.83 [0.67, 1.03]

5.3 unclassified

6

5652

Risk Ratio (M‐H, Fixed, 95% CI)

1.12 [0.73, 1.72]

6 Small‐for‐gestational age Show forest plot

32

24310

Risk Ratio (M‐H, Fixed, 95% CI)

0.92 [0.85, 1.00]

6.1 entered into the study < 20 weeks

15

12150

Risk Ratio (M‐H, Fixed, 95% CI)

0.89 [0.79, 1.00]

6.2 entered into the study > 20 weeks

17

6634

Risk Ratio (M‐H, Fixed, 95% CI)

0.93 [0.81, 1.08]

6.3 unclassified

3

5526

Risk Ratio (M‐H, Fixed, 95% CI)

1.00 [0.82, 1.21]

Figures and Tables -
Comparison 2. Antiplatelet agents versus placebo/no antiplatelet (subgrouped by gestation at entry)
Comparison 3. Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo)

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Pregnancy induced hypertension Show forest plot

31

21754

Risk Ratio (M‐H, Fixed, 95% CI)

0.98 [0.90, 1.06]

1.1 placebo

25

20411

Risk Ratio (M‐H, Fixed, 95% CI)

0.97 [0.89, 1.06]

1.2 no placebo

6

1343

Risk Ratio (M‐H, Fixed, 95% CI)

1.02 [0.80, 1.30]

2 Proteinuric pre‐eclampsia Show forest plot

43

33439

Risk Ratio (M‐H, Fixed, 95% CI)

0.81 [0.75, 0.88]

2.1 placebo

35

31958

Risk Ratio (M‐H, Fixed, 95% CI)

0.83 [0.77, 0.90]

2.2 no placebo

8

1481

Risk Ratio (M‐H, Fixed, 95% CI)

0.46 [0.30, 0.70]

3 Placental abruption Show forest plot

16

25806

Risk Ratio (M‐H, Fixed, 95% CI)

1.06 [0.85, 1.32]

3.1 placebo

13

24644

Risk Ratio (M‐H, Fixed, 95% CI)

1.08 [0.86, 1.36]

3.2 no placebo

3

1162

Risk Ratio (M‐H, Fixed, 95% CI)

0.80 [0.35, 1.87]

4 Preterm birth Show forest plot

28

31845

Risk Ratio (M‐H, Fixed, 95% CI)

0.93 [0.88, 0.98]

4.1 placebo

23

30464

Risk Ratio (M‐H, Fixed, 95% CI)

0.93 [0.88, 0.98]

4.2 no placebo

5

1381

Risk Ratio (M‐H, Fixed, 95% CI)

0.90 [0.76, 1.08]

5 Fetal, neonatal or infant death Show forest plot

38

34010

Risk Ratio (M‐H, Fixed, 95% CI)

0.85 [0.75, 0.97]

5.1 placebo

30

32381

Risk Ratio (M‐H, Fixed, 95% CI)

0.88 [0.76, 1.00]

5.2 no placebo

8

1629

Risk Ratio (M‐H, Fixed, 95% CI)

0.56 [0.33, 0.94]

6 Small‐for‐gestational age Show forest plot

32

24310

Risk Ratio (M‐H, Fixed, 95% CI)

0.96 [0.88, 1.04]

6.1 placebo

27

22830

Risk Ratio (M‐H, Fixed, 95% CI)

0.94 [0.87, 1.03]

6.2 no placebo

5

1480

Risk Ratio (M‐H, Fixed, 95% CI)

1.04 [0.83, 1.31]

Figures and Tables -
Comparison 3. Antiplatelet agents versus placebo/no treatment (subgrouped by use of placebo)
Comparison 4. Aspirin versus placebo/no treatment (subgrouped by dose)

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Pregnancy induced hypertension Show forest plot

30

21715

Risk Ratio (M‐H, Fixed, 95% CI)

0.98 [0.91, 1.06]

1.1 75 mg or less aspirin

18

17287

Risk Ratio (M‐H, Fixed, 95% CI)

1.00 [0.92, 1.10]

1.2 > 75 mg aspirin

12

4428

Risk Ratio (M‐H, Fixed, 95% CI)

0.91 [0.78, 1.07]

2 Proteinuric pre‐eclampsia Show forest plot

41

33369

Risk Ratio (M‐H, Fixed, 95% CI)

0.82 [0.76, 0.89]

2.1 75 mg or less aspirin

22

28404

Risk Ratio (M‐H, Fixed, 95% CI)

0.86 [0.79, 0.93]

2.2 > 75 mg aspirin

19

4965

Risk Ratio (M‐H, Fixed, 95% CI)

0.49 [0.38, 0.65]

3 Placental abruption Show forest plot

16

25806

Risk Ratio (M‐H, Fixed, 95% CI)

1.06 [0.85, 1.32]

3.1 75 mg or less aspirin

11

22071

Risk Ratio (M‐H, Fixed, 95% CI)

1.05 [0.83, 1.33]

3.2 > 75 mg aspirin

5

3735

Risk Ratio (M‐H, Fixed, 95% CI)

1.11 [0.60, 2.05]

4 Preterm birth Show forest plot

27

31787

Risk Ratio (M‐H, Fixed, 95% CI)

0.94 [0.89, 0.99]

4.1 75 mg or less aspirin

18

27823

Risk Ratio (M‐H, Fixed, 95% CI)

0.94 [0.89, 0.99]

4.2 > 75 mg aspirin

9

3964

Risk Ratio (M‐H, Fixed, 95% CI)

0.94 [0.76, 1.16]

5 Fetal, neonatal or infant death Show forest plot

37

33990

Risk Ratio (M‐H, Fixed, 95% CI)

0.85 [0.74, 0.96]

5.1 75 mg or less aspirin

25

29722

Risk Ratio (M‐H, Fixed, 95% CI)

0.85 [0.74, 0.97]

5.2 > 75 mg aspirin

12

4268

Risk Ratio (M‐H, Fixed, 95% CI)

0.79 [0.48, 1.28]

6 Small‐for‐gestational age Show forest plot

30

24242

Risk Ratio (M‐H, Fixed, 95% CI)

0.92 [0.85, 1.00]

6.1 75 mg or less aspirin

18

19663

Risk Ratio (M‐H, Fixed, 95% CI)

0.93 [0.84, 1.02]

6.2 > 75 mg aspirin

12

4579

Risk Ratio (M‐H, Fixed, 95% CI)

0.91 [0.78, 1.05]

Figures and Tables -
Comparison 4. Aspirin versus placebo/no treatment (subgrouped by dose)
Comparison 5. Antiplatelet agent + other agents versus placebo/no treatment (subgrouped by type of agent)

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Proteinuric pre‐eclampsia Show forest plot

6

589

Risk Ratio (M‐H, Fixed, 95% CI)

0.20 [0.10, 0.39]

1.1 aspirin + dipyridamole

4

442

Risk Ratio (M‐H, Fixed, 95% CI)

0.29 [0.14, 0.61]

1.2 aspirin + fish oil + vit C + vit E

1

127

Risk Ratio (M‐H, Fixed, 95% CI)

0.07 [0.01, 0.54]

1.3 dipyridamole + heparin

1

20

Risk Ratio (M‐H, Fixed, 95% CI)

0.09 [0.01, 1.45]

2 Fetal or neonatal death Show forest plot

5

462

Risk Ratio (M‐H, Fixed, 95% CI)

0.49 [0.23, 1.03]

2.1 aspirin + dipyridamole

4

442

Risk Ratio (M‐H, Fixed, 95% CI)

0.52 [0.24, 1.13]

2.2 dipyridamole + heparin

1

20

Risk Ratio (M‐H, Fixed, 95% CI)

0.24 [0.01, 4.44]

Figures and Tables -
Comparison 5. Antiplatelet agent + other agents versus placebo/no treatment (subgrouped by type of agent)