May 2021

The purpose of this document is to keep a working list of guidelines with information about aspirin for disease prevention in pregnancy.  The guidelines themselves should be read for further information.

Aspirin and pre-eclampsia

The International Federation of Gynaecology and Obstetrics recommend that women identified as high risk of pre-eclampsia during first trimester screening should be given aspirin prophylaxis (150mg at night from 11-14 weeks gestation until delivery or the diagnosis of pre-eclampsia). They do not advocate a policy of low-dose aspirin for all pregnant women.

Poon LC, Shennan A, Hyett JA et al The International federation of Gynaecology and Obstetrics (FIGO) initiative on pre-eclampsia: a pragmatic guide for first-trimester screening and prevention. Int J Gynecol Obstet 2019; 145 (Suppl.1) 1-33. @

https://obgyn.onlinelibrary.wiley.com/doi/epdf/10.1002/ijgo.12802

A Cochrane review from 2019 concluded that low dose aspirin does slightly reduce the risk of pre-eclampsia and its complications but that further research is required to identify those most likely to benefit.

Duley L, Meher S and Hunter KE et al. Antiplatelet agents for preventing pre-eclampsia and its complications Cochrane Database of Systematic Reviews Oct 2019

https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD004659.pub3/full

UK guidelines preeclampsia

NICE 2019 recommends that women who are at high risk of pre-eclampsia take 75-150mg of aspirin daily from 12 weeks until the birth of the baby. They define women at high risk as those with; hypertension during a previous pregnancy, chronic kidney disease, an auto immune disease (e.g. systemic lupus erythematosus or antiphospholipid syndrome), diabetes (type 1 or 2) and/or chronic hypertension. In addition, they advise women with more than one moderate risk factor for pre-eclampsia to take low-dose aspirin from 12 weeks until birth. Moderate risk factors for pre-eclampsia are; first pregnancy, age 40 or above, a pregnancy interval of more than 10 years, obesity, family history of pre-eclampsia and a multiple foetus pregnancy.

NICE NG133 Hypertension in pregnancy: diagnosis and management. 2019 @ https://www.nice.org.uk/guidance/ng133/chapter/Recommendations

USA guidelines preeclampsia

The U.S. Preventative services Task Force (USPSTF) recommends (Grade B) low-dose aspirin (81 mg per day) after 12 weeks gestation as a preventative medication in women at high risk of pre-eclampsia.

USPSTF Low-dose aspirin use for the prevention of morbidity and mortality from preeclampsia: preventative medication. 2014 (currently being updated) available @ https://www.uspreventativeservicestaskforce.org/uspstf/recommendations/low-dose-aspirin-use-for-the-prevention-of-morbidity-and-mortlality-from-preeclampsia-preventative-medication