The efficacy of low-dose aspirin combined with low-molecular-weight heparin treatment for improving antiphospholipid syndrome and maternal-fetal outcome of patients is recognized by various countries and recommended by the guidelines. However, there are still 20-30% of APS patients whose treatment fails. Therefore, the standard treatment effect is still not ideal, and other treatment options need to be explored. The purpose of this study is to conduct a randomized double-blind, parallel controlled study of patients with recurrent miscarriage and APS in addition to standard treatment, plus hydroxychloroquine sulfate (HCQ) or placebo, to observe the effects of HCQ on pregnancy outcome in patients with abortion and APS, to evaluate the effectiveness and safety of HCQ treatment.

This study uses a multi-center, double-blind, randomized, parallel-controlled research model. In addition to the standard anticoagulant drugs for antiphospholipid syndrome, patients with recurrent miscarriage and APS who meet the enrollment criteria will be randomly divided into hydroxychloroquine sulfate( HCQ) group or placebo group, and randomly assigned according to a 1:1 ratio. Observe the efficacy and safety.

The Hydroxychloroquine sulfate(HCQ) group is the test group. Hydroxychloroquine sulfate 0.2g/d (sig: 0.1g bid po) will be applied 3 months before pregnancy, pregnancy will be started at the 4th month, and aspirin 50mg/d will be added after menstruation( sig: 25mg bid po), low molecular weight heparin 4000-6000 U/d after ovulation or 1 week before embryo transplantation; the placebo group is the control group, and placebo 0.2g/d (sig: 0.1 g bid po) from the fourth month of pregnancy, add aspirin 50mg/d (sig: 25mg bid po) after menstruation, and add low molecular heparin 4000-6000 U/d after ovulation or 1 week before embryo transplantation Both groups were followed up by telephone every 1 month to obtain medication compliance, whether there were adverse reactions, etc., and both oth groups were followed up every 3 months for non-pregnant women by outpatient service , until pregnancy. If the patient is not pregnant within one year, The clinical study of this patient will be terminated, and the patients will be followed up for adverse reactions by telephone one month and three months after withdrawal. If you are pregnant, follow up in the first trimester immediately, and arrange a follow-up every three months thereafter (defined as follow-up in the first trimester, follow-up in the second trimester and follow-up in the third trimester). The drug was discontinued on the day of delivery and the postpartum follow-up was completed 6 weeks after delivery. So, therefore, the entire study time is approximately 27 months.

The researcher mainly records the subjects' vital signs, laboratory indicators, adverse events and combined medications, as well as related indicators of pregnancy check-ups (such as uterine artery blood flow, presence or absence of pregnancy complications, fetal complications, etc.)

Inclusion Criteria:

• Patients who want to conceive，with recurrent miscarriage and antiphospholipid syndrome (APS) .
• Agree to join the study and sign the informed consent of the study.

Exclusion Criteria:

• Women who are already pregnant.
• Allergies or adverse events to Hydroxychloroquine(HCQ),such as allergies to the active substance -aminoquinoline or allergies to HCQ or any other chemical components of placebo.
• Patients with any changes in the retina or visual field caused by treatment with 4-aminoquinoline compounds;
• HCQ is currently being used
• Weight <45kg
• Psoriasis
• Uncontrolled epilepsy
• Anti-ENA antibody positive
• Renal replacement therapy
• Other serious active complications (human immunodeficiency virus, hepatitis B)
• Porphyria
• History of retinopathy
• History of galactose intolerance, history of lactase deficiency, or history of glucose-galactose malabsorption
• Participate in any other clinical trial drug research at the same time.
• Previous treatment failure with Hydroxychloroquin
• Others: such as poor compliance, or those who cannot be followed up on schedule due to certain factors.