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There will be several signs to help you anticipate when labor is imminent; watch for them so you can be prepared when your dog enters labor. Her teats will appear enlarged when your dog is close to giving birth because her milk is coming in. This can happen within a few days or as labor begins, so watch closely. The vulva will start to get more relaxed a few days before labor. The dog's temperature will also drop a degree or so about 24 hours before labor. Take her temperature every morning for the last week or two of pregnancy to get an idea of her normal temperature. To take her temperature, lubricate a rectal thermometer and insert it about half an inch. Leave the thermometer in for about three minutes to get an accurate reading. Her normal temperature will likely range between 101 and 102.5 degrees Fahrenheit. When you notice a drop of a degree or more, it's a likely sign she'll go into labor in 24 hours or less. In the early stages of labor, your dog may pant, whimper, move around as though uncomfortable, or hide. She will probably not want to eat, but be sure to offer her water, though she may also not drink. When she has a contraction, it will be easy to identify--it will appear as a sort of wave across her belly. If you see contractions and suspect she is in labor, let her have access to her nesting area and monitor her from afar. Many dogs will give birth during the night to have ultimate privacy. You don't need to hover, but you should start paying attention to the timing of contractions and the delivery of puppies. Again, observe from a respectful distance and don't intervene unless necessary. You will notice her contractions become more frequent and/or pronounced as she gets closer to delivery. She may stand up, which is fine--don't try to force her to lie down. As she begins to deliver the puppies, keep a close eye on each birth and watch for warning signs of problems. The puppies may be born either tail or head first; both are normal. She may yelp or whimper as the pup comes out, which is to be expected. But if your dog appears to be in extreme or abnormal pain, call your veterinarian immediately. Usually, a pup will appear every thirty minutes or so, after ten to thirty minutes of forceful straining (though she may go as long as four hours between pups). Call your veterinarian If no pup appears within 30-60 minutes of hard contractions. Also call your vet if it's been over four hours since the last delivery and you know there are still unborn puppies. Keep an eye on each pup after it's born and watch for signs of problems, though you likely won't need to intervene. When the mother delivers, the pup will be in a sac; she should tear it open and then chew off the umbilical cord and lick the pup. It's usually best to let her do this without human assistance because it's part of her bonding experience with the puppies. If she doesn't tear open the sac within about two to four minutes, however, you should gently open the sac yourself with a clean hand. Clear all fluid away from the pup's nose and mouth, then rub the pup vigorously but gently to stimulate breathing. Make sure the puppies are warm, but, again, don't intervene unless you see a problem. Neonatal death (ie, stillbirths or pups that survive only a few hours or days) is relatively common for most littered mammals, so be prepared for this possibility. If you see a newborn pup that is not breathing, try to clear the mouth and stimulate the puppy by rubbing its body to see if you can get it breathing.
Watch carefully for signs of labor. Watch for contractions. Monitor the birthing. Pay attention to each birth. Monitor each pup after delivery.