Baby Aspirin in Late Pregnancy and Delivery

If you have a disorder that causes your blood to develop clots, you may need to take low-dose baby aspirin during pregnancy. Often prescribed in conjunction with heparin, another drug that prevents clotting, baby aspirin reduces the ability of platelets to stick together. Platelets form clots at bleeding sites that prevent excess blood loss. Most doctors suggests stopping baby aspirin around 36 weeks of pregnancy to reduce the risk of excessive blood loss at the time of delivery.


Baby aspirin alone or taken with heparin or other blood thinners reduces the risk of pregnancy loss from thrombotic disorders such as antiphospholipid syndrome or inherited blood disorders. As many as 10 to 20 percent of women who suffer from recurrent miscarriage, defined as three or more pregnancy losses in a row, have antiphospholipid syndrome, according to the March of Dimes. Thrombolytic disorders can also cause placental abruption, preeclampsia or preterm delivery, all potentially life-threatening complications that can threaten you or your baby.


Pregnant woman lying on sofa in sitting room

Can Taking Baby Aspirin Help With a Pregnancy?

Learn More

Because baby aspirin disrupts platelet aggregation -- the ability of platelets to stick together -- it could increase blood loss at the time of delivery. Women normally lose around 200 to 300cc of blood during a normal delivery, with amounts over 500cc considered maternal hemorrhage, according to certified nurse-midwife Peg Palumbo. The amount of 30cc equals 1 oz., so 300cc equals around 10 oz. of blood loss. Blood loss over 700cc to 1,000cc can cause shock or other serious maternal consequences.


Follow your doctor's instructions on when to stop taking baby aspirin. Most doctors suggest stopping the drug once your baby is big enough to deliver with little chance of complications, normally around 36 weeks. You may need to restart baby aspirin after delivery and continue it for six to eight weeks after delivery, rheumatologist Peter Shur reports on UpToDate.


Pregnant woman lying on sofa in sitting room

hCG Levels After a Miscarriage

Learn More

Take baby aspirin only if your doctor orders it. Do not substitute regular aspirin for baby aspirin. Regular aspirin can cause:

  • complications during pregnancy
  • including an increased risk of stillbirth
  • growth retardation
  • birth defects
  • bleeding into the fetal brain
  • fetal heart problems

Low-dose aspirin does not appear to have these risks, reports.