The efficacy and safety of taking aspirin before the eleventh week of pregnancy have not been demonstrated for this gestational problem, which affects about 5% of women
Preeclampsia is a problem of pregnancy hypertension that increases the risk of premature delivery and leads to the death of approximately 60,000 women and 500,000 children worldwide each year, mainly in developing countries. The probability of this problem occurring decreases by 60% in women who start taking aspirin daily from the 11th week of pregnancy. From there to think that it would be advantageous to start this treatment earlier, there is only one step, which should be wary, warns a team of French and Canadian researchers led by Emmanuel Bujold, from the Faculty of Medicine and the Research Center of the CHU of Quebec - Laval University.
Professor Bujold and colleagues conducted a targeted survey of 12 maternal-fetal medicine or infertility specialists practicing in Canada and the United States. They also scrutinized Canadian data on medications taken by women prior to the first ultrasound, a test that usually takes place between 11 and 13 weeks of pregnancy.
The findings, which appear in the December issue of the journal Pregnancy Hypertension, show that 11% of pregnant women who are not in their first pregnancy take aspirin before the 11th week of gestation. Aspirin use also appears to be common during this period among women who are being monitored for fertility problems or recurrent miscarriages.
The researchers reviewed studies of aspirin use before 11 weeks of pregnancy and their findings suggest caution. Early initiation of treatment does not provide any additional benefit and may even reduce the efficacy observed when initiated after 11 weeks of gestation.
"This practice should be replaced with evidence-based screening and optimal interventions for the prevention of preeclampsia."
-- Emmanuel Bujold, on the routine prescription of aspirin to women undergoing assisted reproduction
The researchers note that daily aspirin is routinely prescribed to women who undergo assisted reproduction, even though there is little evidence to support this. "This practice should be replaced by evidence-based screening and optimal interventions for the prevention of preeclampsia in these women," says Emmanuel Bujold.
In addition to Professor Bujold, other members of the Laval University community who signed the article in Pregnancy Hypertension are Chantale Vachon-Marceau, Stéphane Côté and Sarah Maheux-Lacroix.