Usage of Heparin and Aspirin for Recurrent Miscarriages
In recent years, many doctors are deliberately prescribing anticoagulant and antithrombotic medications such as Herapin and Aspirin as a common course of treatment for recurrent miscarriages. It has been widely used to stimulate uterine blood flow for expectant mothers with uterine blood insufficiency and recurrent miscarriage. It is also believed to be safe as it does not pass through the placenta.
However, such anticoagulant medications do not treat the conditions that lead to uterine blood insufficiency and has no impact in the treatment of recurrent miscarriage, potentially it can increase the risk of it.
Why is it being prescribed for patients?
Antiphospholipid antibodies are believed to be associated with a higher risk of pregnancy complications, including the risk of pregnancy loss. Use of antithrombotic drugs during pregnancy are wrongly believed to help prevent pregnancy loss for women who have had recurrent miscarriages. Although Aspirin is in fact an anti‐inflammatory drug that reduces platelet aggregation and blood clotting & Heparin is a potent anticoagulant that prevents blood clot formation, it has been proven in recent studies that it has little to no effect in the treatment and prevention of pregnancy losses.
Contributing Factors of Uterine Blood Insufficiency
Uterine blood insufficiency leads to recurrent miscarriages because it restricts embryo/fetal growth.
Constriction of Blood in Uterine Tissues
- Naive Uterus
- Septate Uterus
The two conditions above are uterine malformations. Such uteruses are made of excessive connective tissues as compared to smooth muscles. This congenital disruption in the ration of these two specific tissues affects the blood vessels both in quality and quantity, hence, there is insufficient blood in the uterus to nurse an embryo or fetal growth, inevitably leading to a pregnancy loss, if no treatment is received for the patient.
Poor quality of uterine blood vessels: too few and too thin
Competition for Blood Supply
- Uterine Fibroid(s)
- Other growths such as cysts, and polyps
Multiple fibroids or a singular, large fibroid in the uterus will compete with the embryo/fetus for blood supply and nutrients. As a result, the pregnancy will not have sufficient blood and nutrients for optimal growth.
Symptoms of Uterine Blood Insufficiency
The first symptom of a restricted embryo/fetal development resulting from uterine blood insufficiency is an hCG level lower than expected, where hCG is not doubling every three days. However, since the corpus luteum function is fine, the progesterone level will still be within the acceptable range.
Why Anticoagulant Drugs are Ineffective in Miscarriage Prevention
Prescribing anticoagulant drugs for uterine blood insufficiency to prevent miscarriages makes theoretical sense since they thin out the blood and increase uterine blood flow.
However, as mentioned above, uterine blood insufficiency results from organic diseases such as excessive uterine connective tissues or fibroids growth. Organic diseases can only be treated with surgery and not with medications. Hence, Heparin and Aspirin are not effective in preventing miscarriages caused by uterine blood insufficiency.
Dangers of Anticoagulant Drugs Usage During Pregnancy
During pregnancy, an expectant mother is in a hypercoagulability state where they are more prone to develop blood clots. However, this is not an unfavorable occurrence. It is an adaptive process during pregnancy to prevent postpartum bleeding.
Hence, prescribing anticoagulant drugs such as Heparin and Aspirin during pregnancy alters the body’s natural state during pregnancy, from hyper-coagulant to hypo-coagulant. It thins out the expectant mother’s blood, creating a risk of hemorrhaging during pregnancy or postpartum.
Proper Recurrent Miscarriage Prevention
The proper and effective way of preventing recurrent miscarriages is with thorough diagnostic testing to find the root cause. Uterine blood insufficiency is a symptom of connective tissues restricting blood supply or abnormal growths within the uterus competing with embryo/uterus for blood. After finding the underlying root cause, patients can then undergo the necessary treatment.
Uterine blood insufficiency conditions such as infantile uterus, uterus septate, or uterine fibroids can be corrected with surgery.
Antai hospital provides a comprehensive list of diagnostic testing and treatment. Antai hospital specializes in recurrent miscarriages with experts in reproductive immunological disorders. Each year, Antai hospital treats 300-400 couples to carry their baby to full term successfully.