Weight loss challenge with Hubby

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Four years ago, due to hypothyroidism, I had gained 25 lbs before finally getting it stable. (at least I think it is now) The last 2 years I have been on fertility drugs, gaining another 20 lbs. (I have PCOS) That's 45 lbs in 4 years! I am 30, 5' 9" weighing 195. When we got married 4 years ago i was a healthy, athletic, tone, 150 lbs. I soooooo want to be there again! I have decided to stop the fertility drugs for a few months, and figure this is a good time to tackle those extra lbs til I have to start them again.

My Husband started a silly weight loss challenge a year ago with a buddy. But in order to be the one to lose the most lbs, they both gained 30 lbs before the competition started. Unfortunately, 2 days after the diet challenge officially started, my husband's brother died unexpectedly. Which in turn, put him in a major depression for 6 months, and off and on since then. Needless to say, he never lost those extra 30 he gained, nor the weight he wanted to lose before that. But now he is motivated and wanting to lose!


So... I'm thinking of a little husband-wife challenge. But I'm having troubles coming up with incentives to work for. What would make it worth it, without costing a whole lot? What could he win? Or me? What should terms be? Any ideas?? Help!