A national study on anticoagulant use for recurrent spontaneous abortion in China

In China, recurrent spontaneous abortion (RSA), the consecutive loss of two or more pregnancies, affects many couples. A contributing factor is abnormal blood coagulation, which can disrupt placental blood flow. This disruption deprives the fetus of oxygen and nutrients, potentially leading to miscarriage. Anticoagulant therapy is a common intervention to improve pregnancy outcomes, though strong evidence to support this approach is still limited.

A comprehensive six-year study now provides a crucial analysis of anticoagulant use for RSA treatment in China. Published in Reproductive and Developmental Medicine, the research examined more than 10,000 prescriptions from nine major cities between 2016 and 2021. The study details prescribing patterns, drug cost trends, and the frequency of medically appropriate prescriptions.

The investigation identified eight anticoagulants in use. Enoxaparin, a low-molecular-weight heparin (LMWH), was the predominant choice. It accounted for over half of all prescriptions by 2021 and was the most frequently used treatment from 2018 onward. The use of other LMWHs, like dalteparin and nadroparin, decreased significantly. In contrast, fondaparinux, a newer anticoagulant, demonstrated steady growth in usage.

“It makes sense that doctors prefer enoxaparin, because we know it well and have a lot of experience using it,” noted Dr. Wang Xianli, one of the study’s lead researchers.  But what’s interesting is the growing use of fondaparinux. That’s not really covered by current guidelines, so it shows there’s still a gap between what the official recommendations say and what’s actually happening in day-to-day practice.”

Enoxaparin's prevalence reflects both clinical preference and supporting evidence, which indicates a favorable safety profile. Fondaparinux, however, is not officially recommended for RSA in Chinese or international guidelines, except for patients with heparin intolerance. Its increasing use suggests that clinicians view it as a safe and effective alternative.

The analysis also focused on drug affordability. Fondaparinux remained the most expensive option throughout the study period, although its cost decreased. By 2021, enoxaparin and several other LMWHs were not only the most widely used but also among the most cost-effective treatments.

This shift in cost was influenced by national drug policy reforms, including the 2017 elimination of hospital drug markups (an extra percentage on top of the wholesale price) and the implementation of bulk procurement programs.

A significant finding was a high rate of inappropriate prescriptions. In many cases, prescriptions were issued without documented medical justification. Although this percentage declined over time, it remains considerable. The researchers note that incomplete clinical records may contribute to this trend. Nevertheless, the findings underscore a need for stricter prescribing protocols and enhanced collaboration between physicians and pharmacists.