Studies of low-dose aspirin (LDA) with heparin compared with LDA alone in women with history of fetal loss
| Reference | Design | Comparison | Percent with explicitly fetal loss | Intervention | Control | Number of patients, intervention | Number of patients, control | Events, intervention | Events, control | Relative effect (95% CI) | Study quality |
| Live births | |||||||||||
| Muñoz-Rodriguez et al 199932 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 12 | 18 | 10 (83%) | 14 (78%) | – | High quality |
| Naru et al 201069 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 35 | 29 | 35 (100%) | 29 (100%) | – | High quality |
| Cohn et al 201070 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 62 | 98 | 49 (79%) | 61 (62%) | – | High quality |
| Mohamed and Saad 201471 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 47 | 23 | 43 (91%) | 15 (65%) | – | Intermediate quality |
| Ruffatti et al 201472 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 104 | 16 | 81 (77.8%) | 11 (68.7%) | – | High quality |
| Total | Indirect | 260 | 184 | 218 | 130 | RR=1.19 (1.06, 1.32) I2=88% | |||||
| Miscarriages | |||||||||||
| Cohn et al 201070 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 62 | 98 | 11 (16%) | 38 (37%) | – | High quality |
| Mohamed and Saad 201471 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 47 | 23 | 4 (9%) | 8 (35%) | – | Intermediate quality |
| Total | Indirect | 109 | 121 | 15 | 46 | RR=0.40 (0.24, 0.67) I2=0% | |||||
| Pre-term delivery | |||||||||||
| Naru et al 201069 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 35 | 29 | 12 (34.3%) | 9 (31%) | RR=1.10 (0.54 to 2.25) | High quality |
| Pre-eclampsia | |||||||||||
| Naru et al 201069 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 35 | 29 | 10 (28.6%) | 6 (20.7%) | – | High quality |
| Mohamed and Saad 201471 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 47 | 23 | 3 (7%) | 9 (39%) | – | High quality |
| Total | Indirect | 82 | 52 | 13 | 15 | RR=0.59 (0.32, 1.11) I2=87% | |||||
| Intrauterine growth retardation | |||||||||||
| Naru et al 201069 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 35 | 29 | 8 (22.8%) | 5 (17.2%) | – | High quality |
| Mohamed and Saad 201471 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 47 | 23 | 6 (12%) | 8 (33%) | – | Intermediate quality |
| Total | Indirect | 82 | 52 | 14 | 13 | RR=0.69 (0.36, 1.32) I2=70% | |||||
| Maternal thrombosis | |||||||||||
| Naru et al 201069 | Retrospective cohort | Indirect | NR | LDA+LMWH | LDA | 35 | 29 | 0 | 0 | RR not estimable | High quality |
LMWH, low molecular weight heparin;NR, not reported; RR, risk ratio.