Participants
Uterine anatomy abnormalities, thyroid disease, immune dysfunction, proteinuria, myocardial ischemia, hypoglycemia, miscarriages, renal insufficiency, hypertension
THYROID DISEASE, MYOCARDIAL ISCHEMIA, REPRODUCTIVE TRACT INFECTION, HYPOGLYCEMIA, CHROMOSOMAL ABNORMALITIES, MISCARRIAGES, RENAL INSUFFICIENCY, HYPERPROLACTINEMIA, HYPERTENSION, PROLIFERATIVE RETINOPATHY, UTERUS
According to the RSA diagnostic criteria, adult women aged 22 to 42 years who experienced two or more miscarriages or three or more consecutive cycles of high-quality embryo transfer without pregnancy were recruited, with blood lead concentration > 20 µg/l. In this populations, patients with immune dysfunction and abnormalities of glucose or lipid metabolisms were also enrolled. Key exclusion criteria were: (1) Un-heathy life styles such as smoking and drinking. (2) Excessive exposure to harmful chemicals. (3) Genetic problems such as chromosomal abnormalities. (4) Uterine anatomy abnormalities such as a mediastinal uterus and cervical insufficiency. (5) Abnormal endocrine function such as thyroid disease and hyperprolactinemia. (6) Reproductive tract infections. (7) Use of antibiotics within 90 days before enrollment. (8) The habits of taking biotic products such as probiotics, prebiotics, synbiotics, or postbiotics. (9) A history of administrations with hypoglycemia and hypolipidemic drugs during the past two months. (10) The changed amplitude of body weight over 5% in the past two months. Patients with the coexisting conditions (i.e., severe myocardial ischemia, proliferative retinopathy, renal insufficiency with the proteinuria > 1 g/day, hypertension with systolic pressure > 160 mmHg or diastolic blood pressure > 95 mmHg) were also excluded.