Using Mifepristone and Misoprostol to end a current pregnancy will not have any effect or cause birth defects  to a future pregnancy. Both of the abortion pills (Mifepristone and Misoprostol) are rapidly removed from the body, thus they do not have any effect on future pregnancies.
 Women on Web. What are the chances that the fetus will be malformed if you have an ongoing pregnancy? Retrieved from: https://www.womenonweb.org/en/page/478/what-are-the-chances-that-the-fetus-will-be-malformed-if-you-have-an-ongoing-p