How can I tell if my dog is having complications during labor?

During labor. The big four categories. If it's been more than two hours between a puppy. So she's had one, and it's been more than two hours; you need to put it on your radar that there might be a complication. If she's actively been pushing and it's been more than 30 minutes and a puppy hasn't come out. So that's not just laying there and hanging out—that's actively pushing. She should produce a puppy within 30 minutes of that; otherwise, again, it could be a complication. Black discharge at any point is concerning. Green discharge before the first puppy, or if it's excessive, can be concerning. And then blood. Birthing in dogs is actually not a bloody process. So if you see just straight blood, then that should be something you're watching out for.