I had a D & C after a failed pregnancy exactly one week ago. The doctor said no intercourse for 4 weeks. Does this mean no orgasm by masturbation? Or just no penetration? I understand the risk of infection with intercourse, but no where on the internet does it say anything about orgasm. Is it safe?

I am glad you understand the risk for infection. But even masturbation give rise to risk for infection.

See it takes about 4 weeks for your cervix will still be open for that 4 weeks. Anything to introduce to the vagina wither inside or out poses an infection risk.

Is orgasm more important than your health? I didn't think so.

If you wait another week or two, then maybe, but you better make sure everything is clean and germ free.