Hello Thanks for your query. Your friend needs to be thoroughly investigated before proceeding with this pregnancy. Some possible causes that I can think of are - diabetes hypertension autoimmune conditions like anti phospholipid syndrome fetal hydrops genetic or chromosomal anomalies intra uterine infections rare congenital syndromes cervical or uterine abnormalities thyroid disorders. She needs to look up a high risk specialist, undergo thorough evaluation and proceed accordingly. take care.