Arthrotec is a combination of diclofenac and misoprostol.
Diclofenac is a NSAID (Non-steroidal anti-inflammatory
Drug) it works much like Ibuprofen or Aleve. Misoprostol is a synthetic (man-made) substance that stimulates secretion of mucus in the GI tract. Mucus helps protects the lining of the stomach. It's suppose to help reduce ulcers sometimes caused by a NSAID.
I've not seen literature that says Arthotec is contraindicated in ppl that take birth control medications.