Table 1 Characteristics of the included trials
Reference | n | GA at recruitment(days) | Inclusion criteria (the criteria of high risk of preeclampsia) | Concomitant use of aspirin | Interventions (sample size) | Outcome | |
|---|---|---|---|---|---|---|---|
Experiential group | Control group | ||||||
Fawzy et al. [14] | 107 | 33–49 | >= three documented IRM, no other reason for anticoagulation | No | Enoxaparin, 2000 IU daily (57) | Placebo (50) | Live births, preeclampsia, preterm delivery, gestational diabetes, and neonatal outcome |
Rey et al. [15] | 116 | 51–102 | Complications in the immediate previous pregnancy without previous venous or arterial thrombotic event | The use of aspirin according to local standard practice for high-risk pregnancies at each center | Dalteparin, 4000 IU in women < 60 kg, 5000 IU in women 60–90 kg, 6000 IU in women > 90 kg (57) without/with Aspirin (51) | Aspirin (46) or not (11) | Severe PET, newborn weight < = the 5th percentile, major abruptio placentae and non-severe PET, newborn weight between the 6th and 10th percentile and gestational age at delivery |
Gris et al. [16] | 160 | 35–50 | Abruptio placentae during the first pregnancy, without absolute indication for anticoagulant therapy | Aspirin 100 mg per day to pregnant women according to the usual local protocol | Enoxaparin, 4000 IU daily (80) without/with Aspirin 100 mg daily (15) | Aspirin 100 mg daily (33) or not (47) | preeclampsia, IUGR restricted to newborn birthweight ≤ the 5th percentile, abruptio placenta |
Gris et al. [17] | 224 | 34–50 | Severe PE during the first pregnancy, without absolute indication for anticoagulant therapy | Aspirin 100 mg per day to all women | Enoxaparin, 4000 IU (112) with Aspirin 100 mg daily | Aspirin 100 mg daily (112) | PE, SGA restricted to newborn birthweight ≤ 5th percentile, placenta abruption, IUFD after 20 weeks of gestation |
Martinelli et al. [18] | 135 | 63–91 | History of placenta complications in previous pregnancy without absolute indication for anticoagulant therapy. | No | Nadroparin, 3800 IU (63) | Medical surveillance (65) | Preeclampsia, eclampsia, HELLP syndrome, intrauterine fetal death, FGR, or placental abruption. |
Pasquier et al. [19] | 258 | 29–49 | History of unexplained recurrent miscarriage, without antiphospholipid syndrome and inherited thrombophilia. | No | Enoxaparin, 4000 IU (92) | Standard care and pregnancy monitoring (88) | Intrauterine fetal death, preeclampsia, birth of a small-for-gestational-age neonate, placental abruption, and premature delivery. |
Haddad et al. [20] | 244 | 72–89 | A confirmed history of previous severe preeclampsia, without anticoagulants judged by the local investigator | Aspirin 100 mg per day to all women | Enoxaparin, 4000 IU (122) with Aspirin 100 mg daily | Aspirin 100 mg daily (122) | Maternal death, perinatal death, preeclampsia, small for gestational age (less than the 10th percentile), and placental abruption |
Groom et al. [21] | 149 | 42–111 | At risk of preeclampsia and/or IUGR based on their obstetric history, without previous thrombosis or APS. | Aspirin 100 mg per day to all women | Enoxaparin, 4000 IU (72) with Aspirin 100 mg daily | Aspirin 100 mg daily (77) | Preeclampsia and/or SGA. |
Shaaban et al. [22] | 300 | 42 | 3 or more spontaneous consecutive miscarriages before 20 weeks’ gestation, without any known cause of recurrent miscarriage | No | Tinzaparin sodium, 0.4 mg/kg (109) | No placebo (69) | Take-home baby rate, miscarriage rate, occurrence of pregnancy complications such as IUGR or preeclampsia. |
Llurba et al. [23] | 278 | 60–110 | Severe PE or IUGR in previous pregnancy or positive first trimester screening for PE | Aspirin 100 mg per day to women with prior early-onset PE | Enoxaparin, 4000 IU daily (144) without/with Aspirin 100 mg daily (20) | Aspirin 100 mg daily (26) or not (108) | |