Hello. Welcome to Healthcare Magic. I can understand your concerns about an unwanted pregnancy, but if your wife s pregnancy tests have all been negative since she missed her period, she s probably not pregnant. Thus, misoprostol and mifepristone are not indicated. There are a number of conditions -- aside from pregnancy -- that can delay a woman s period, including severe stress, illness, ovarian cysts, excessive exercise, obesity, extremely low body weight, thyroid disease, autoimmune disorders and certain medications. Despite your desire to avoid disclosing your situation, it would be prudent to seek medical attention to ensure that your wife is not pregnant and to identify the real cause of her delayed period. My best to you and your wife.