Re: possible clogged ducts?
If you're not getting actually plugged ducts- areas inside the breast that are filling up with milk that will not come out- then what you describe isn't really anything to worry about. Since breastmilk isn't pasteurized, homogenized, or filtered, it's normal for it to have a consistency which is different from that of the cow's milk you buy at the store. If you were to take a look at raw cow's milk, you'd see that it is often full of strings and clumps, most of which are caught by the filter that the milk goes through before it hits the tank.
The only problem with stringy, clumpy milk is that it can clog your ducts and can put you at somewhat greater risk of mastitis. It might help to take a soy lecithin supplement and reduce saturated fat in your diet. If that doesn't change the situation, I'd treat this as an inconvenience and try to find a way to strain the milk that allows you to do it less often. Maybe consolidate the milk from all your day's pumping sessions and put it through a coffee filter before breaking it down into smaller portions again? Annoying, I imagine, but better than straining it every time you pump!
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