Are a young man and woman considered fornicators if an illegitimate pregnancy results from the leakage of semen without intercourse, and what are the necessary conditions to rectify their marriage, and will their repentance be accepted without the implementation of the had [prescribed punishment]?

The adultery that necessitates the prescribed punishment (حد) is the penetration of the private part into the private part. Anything less than that is metaphorical adultery, which is an ugly sin. If a pregnancy occurs without penetration, it is considered in the meaning of adultery. Sincere repentance (التوبة النصوح) is obligatory, by abandoning the sin, regretting it, and resolving not to return to it. The expiation for real adultery is repentance, and the validity of repentance does not depend on the execution of the prescribed punishment. Rather, one should conceal oneself, and repentance between the servant and his Lord suffices. Marriage is valid after repentance.