My wife is pregnant & her hcg level is 68858

This because she is expecting. If she weren't then it would be an issue to raise additional questions. However since the case is she it is not anything to raise alarm. This is the hormone used to measure pregnancy.

My wife went for her u/s & the doctor said he couldn't find a heartbeat, but she's not showing any signs of a muscarriage, her hcg level is 68858. Is it possible twins or the heartbeat is hiding, please we are freaking out

How far along is she suspected to be? If early enough, they may not see a heart beat yet. Was this a transvaginal ultrasound? Did they mention seeing the gestational sac and baby?

HCG levels can vary widely and still be considered within a normal range. Do they want to see her again for another ultrasound in a couple of weeks? Do they want to do another blood draw to determine if her level is rising?

She is suppose to be 8 weeks but uncertain

If she is around 8 weeks, the hcg level is well within the norm. Do you know if the ultrasound was transvaginal or abdominal? I would think that they would have said something about coming back in another week or two for another scan as more would be able to be seen at that stage and would give them a better indication of how things are.

I know the uncertainty is frustrating. Sending you positive thoughts!