@ageha @Moon @kaia @matrix @yangwenli The biggest factor I can think of for pregnancy-related long term health decline is terrible nutrition during pregnancy. On that front I don't have any information regarding your demographic, since I don't know where you're from or anything like that.
Bad nutrition during pregnancy can lead to decalcification of bones and teeth, anemia, drastic loss of muscle tissue, organ damage, and a whole bunch of conditions that basically come down to starvation under stress. But that's more irresponsibility or idiocy on the part of the couple than ill will or malice.