Acetylsalicylic acid does not prevent first‐trimester unexplained recurrent pregnancy loss: A randomized controlled trial

Abstract

Treatment with acetylsalicylic acid did not prevent recurrent miscarriage in women with at least three consecutive miscarriages in the first trimester, of unknown reasons and in the same relationship. The fertility prognosis is very good, the live birth rate being > 80% with or without acetylsalicylic acid.

Does low-dose aspirin initiated before 11 weeks’ gestation reduce the rate of preeclampsia?

“…Six out of the eight trials reported the effect of aspirin commenced at <11 weeks' gestation on the rates of preeclampsia. (38,40,50,56,84,85) Four out of the eight trials reported the effect of aspirin started at <11 weeks' gestation on the rates of gestational hypertension. (40,50,84,85) For any hypertensive disorder of pregnancy, there were eight trials reporting the effect of aspirin initiated at <11 weeks' gestation.…”

“…(38,40,50,56,84,85) Four out of the eight trials reported the effect of aspirin started at <11 weeks' gestation on the rates of gestational hypertension. (40,50,84,85) For any hypertensive disorder of pregnancy, there were eight trials reporting the effect of aspirin initiated at <11 weeks' gestation. (38,40,50,56,76,(84)(85)(86) Lastly, six and five of the eight trials reported the effect of aspirin commenced at <11 weeks' gestation on the preterm delivery (40,56,76,(84)(85)(86) and fetal growth restriction, (38,40,50,56,86) respectively.…”

“…Concerning the potential risks of aspirin usage during the very early stage of pregnancy, evidence from clinical trials and meta-analyses on low-dose aspirin in women with previous pregnancy loss has demonstrated that aspirin does not increase the risk of major bleeding, such as gastrointestinal bleeding, or major adverse events, such as congenital or neonatal abnormalities. (40,50,56,60,85,86,117) One study demonstrated that vaginal bleeding was more common in women receiving the treatment, (3.9% vs. 1.3%, p=0.004) but vaginal bleeding was not associated with an increased risk of miscarriage (13% vs. 12%, p=0.781). (117) The largest study included in this meta-analysis has also evaluated complications and safety of pre-conception low-dose aspirin in 1,228 American women.…”

“…The denominator for each outcome in each trial was the number randomized minus any participants whose outcomes were missing or whose pregnancy did not reach 20 weeks. We contacted the authors directly when further clarification on their data, such as the precise gestational age for trial drug administration (74,75) and the results according to singleton or multiple pregnancies, (40,50,56,76) were required. Only one author responded (40) and reported that for singleton pregnancies there were three and six cases of preeclampsia in the aspirin and placebo groups, respectively; and there were two cases of gestational hypertension in each treatment group.…”

“…(17,(28)(29)(30)(31)(32)(33)(34)(35)(36) Following the success of the ASPRE trial, the question that remains is whether high risk women should start low-dose aspirin before pregnancy or during the very early stage of pregnancy. To date, most studies have evaluated the potential benefit of pre-conception or early administration of low-dose aspirin in women with a history of recurrent pregnancy loss, (37)(38)(39)(40) women who have undergone in vitro fertilization (IVF) (28,(41)(42)(43)(44)(45)(46)(47)(48)(49)(50)(51)(52)(53)(54) or women with thrombophilia or antiphospholipid syndrome. (55)(56)(57)(58)(59)(60)(61)(62)(63)(64)(65) It is recognized that these women are at an increased risk of placenta-associated complications of pregnancy, including hypertensive disorder of pregnancy, (66)(67)(68)(69) preterm delivery, (70,…”