90% chance of maternal death?

I have a friend who recently found out he might have impregnated a woman he had a fling with. This woman showed up to his families house, announced to his parents that she was two months along and that their son was the possible father. Shocker for everyone.

However, she mentioned to them that she has a 90% chance of dying during labor, and she wants to ensure her baby will be taken care of. His family is obviously committed to taking care of the baby, but do find it strange that she would carry out a pregnancy that will most likely result in her dying.

She hasn’t been to a doctor yet, she has been kicked out of her home, and she had been sexually active with more than one man during the time she was with my friend. So they are also looking into getting a paternity test.

Our friend is more stable financially than the other men she was with, so they think she might also be trying to pin this on him for that reason. Who knows? This is a crazy situation, but a doctors visit and paternity test should clear all this up I hope.

What diseases can cause such a high maternal death rate?