Not usual to have a retained placenta for a long time, that could have killed her eventually. My guess is that she had a stillbirth at home, which wouldn't have been registered and then she had a retained placenta. That's probably why you think she had a child a year before Steve. Modfied I meant the fact that a stillbirth wouldn't be registered is why you probably thought it was related to a birth a year previously.
Lizzie.