Lifting?

I've heard a number of times that you are not supposed to lift heavy things during pregnancy, but does any one know what exactly the danger is, and how heavy "heavy" is? My older daughter is three and weighs about 55lb (about 25.4kg, I think) and occasionally, I have to lift her. (ie. get her off of something, pick her up onto my lap, whatever.) Also, when I get my weekly groceries, I usually use boxes, and sometimes, they're pretty heavy, too.
Am I really putting my baby at risk? Or does that warning refer to doing heavy lifting all day, or lifting something REALLY heavy?

Hi
I've heard that the only real danger in lifting heavy things is to yourself. I think it has something to do with muscles weakening. Anyway, liftinh heavy things might do you damage but the baby is well cared for inside and unless you fall heavily on your stomach then bubs is pretty safe. If you were to strain your ankle/back/leg when lifting then it may make you collapse.
It's pretty hard to go through 9 months without lifting anything. Just try to limit what you lift and lift from your legs not your back. If you can avoid lifting things then do so otherwise just be cautious.

When I was pregnant with DD I was a landscaper and my Ob told me I was fine to keep doing that as long as I felt OK. That did involve lifting pavers and concrete blocks etc, I think I stopped lifting stuff at about 6 months and I made sure I did not lift anything above about 25 kg. HTH

The no heavy lifting is to protect you. When your joints and ligaments become looser heavy lifting can be very painful and coul cause some damage.

Thanks so much everyone - that's reassuring to hear. Sounds like I won't have any trouble for now anyways. :)