Multicenter Prospective Cohort Study of Twin Maternal-Child Dyads in China

This study follows twin pregnancies and their babies over time in China to understand how carrying twins affects the health of both mother and children. Researchers will collect data from early pregnancy through the children's early development to identify risk factors and improve care for twin pregnancies. **You may be eligible if...** - You are carrying twins - You are between 18 and 45 years old - You are less than 14 weeks pregnant - You plan to receive all prenatal care and give birth at the study hospital - You are willing to sign a consent form **You may NOT be eligible if...** - You have serious mental health conditions or serious maternal illness - You are not planning to receive care at the participating hospital - You are unable to provide informed consent Talk to your doctor to see if this trial is right for you.