hello and welcome,
x-rays do not have any connection with abortion
.but it effects the brain of the growing foetus.
it do not cause any effect in your next pregnancy
if you have not taken x-ray already,its better to avoid if it is not essential.in the early stage of pregnancy or in first trimester,there is more chance of fetal damage due to x-ray exposure.
if the decay is not so deep,formocresol pulpotomy
or indirect pulp capping with calcium hydroxide has to be done.
from your description its not clear that what was the need of prescribing x-ray ,or what was your dental broblem.according to the problem we can decide the treatment and necessity of x-ray.
fetal damage due to x-ray radiation
can even cause mental retardation.