what are the basis of abnormal implantation?

Answer 1

Sometimes the egg implants outside of the uterus ( usually in the fallopian tube), this sometimes happens for no reason but chances are greater if you have endometriosis or polycystic ovary syndrome .. or anything else that has cause scarring in the fallopian tubes.

Answer 2

I'm assuming you mean when a fertilized egg implants in the wrong place, such as the fallopian tube. There is no real basis for this, it's just one of those things that happens unfortunately.

Answer 3

i dont know that would be odd. i would talk t o a doctor asap