Like Joy said, expressing colostrum or any kind of nipple stimmulation can cause contractions, so you kinda want to leave them alone until you give birth. If that's what gets you or your husband going you can keep doing it but try to keep it to a minimum so it does not cause any problems to your pregnancy.
BTW you will still produce milk later on when you give birth, it should not affect supply, it might just increase supply.
Hey there, I am not 100% but, I leaked colostrum occasionally from about 28 weeks, and I still produced it after birth, BUT, if you express your milk for your partner, it would most likely kick off your milk supply and therefore you would be producing actual milk and not colostrum and your baby wouldn't get all the benefits of it. The decision is yours of course but like I say, it is intended for your baby, so your partner may be out of luck :D but again the stuff that is leaking should be fine :) good luck to you and all the best for the rest of your pregnancy. :)
If I'm reading your question right, your partner wants to drink it? I started to leak at 25 weeks or so, and sometimes expressed tiny amounts, (like a drop) and I have a decent milk supply now. I'm not too sure about it though. There's no reason to express any of it now, and I've not really heard of anyone trying. Expressing this now wouldn't produce milk. That only happens after the child is born.
Renoire- nipple stimulation can cause contractions. You shouldn't pump or try to get the colostrum out. Your body will produce colostrum, off and on, until birth and then your milk will come in on the 2nd or 3rd day after birth. There are many books out there on Breastfeeding if you'd like more information.