Women who meet the inclusion criteria at the outpatient clinic of Renji Hospital are recruited in this study from November 2022 to December 2023. Basic information of all subjects is recorded, including number of miscarriages, duration of breastfeeding, comorbidities, and intake of nutritional supplements. Subjects' medication use during the study is recorded as well. Subjects will undergo ultrasound BMD at six time points: before and after medication during pregnancy preparation, at 10, 24, 32 weeks of pregnancy, and at 42 days postpartum. Peripheral blood will also be collected at the time points above to measure serum osteocalcin, blood calcium, blood phosphorus, 25(OH) D, thyroid hormone, and parathyroid hormone levels. Subjects will be followed up to 42 days postpartum to observe pregnancy outcomes and health conditions of the newborn.
The goal of this prospective observational study is to learn about the effect of low molecular weight heparin (LMWH) application on bone mineral density (BMD) and on calcium-phosphorus metabolism in patients with recurrent spontaneous abortion (RSA), and to compare the degree of bone loss and changes in blood calcium and phosphorus in RSA patients and in control groups with normal pregnancy. By monitoring ultrasound BMD and serum indicators related to maternal bone formation and Ca-P metabolism, the association mechanism between long-term use of LMWH, maternal Ca-P regulation and bone loss will be constructed, so as to contribute to clinical treatment and lifestyle guidance during pregnancy in RSA patients.