https://www.scirp.org/reference/referencespapers?referenceid=876566
Simms-Stewart, D., et al. (2009) Retained placenta in homozygous sickle cell disease. Obstetrics & Gynecology, 114, 825-828. doi10.1097/AOG.0b013e3181b6f762
et alretained placentasimmsstewarthomozygous