Please choose the correct ending to complete the given sentence: Pets and Animals: [header] How to help your dog whelp or deliver puppies [title] Take your dog to the veterinarian. [step] If your dog's pregnancy is planned, take her to the veterinarian for a check-up before breeding her. Bring her in again about 30 days into the pregnancy.

Ending1: This gives the vet the opportunity to decide if the pregnancy is appropriate for breeding, and how many puppies the baby needs. The vet should also examine your dog's vulva-the pink uterus between the urethra and urinary tract. Ending2: The vet will run some simple tests to help detect pregnancy changes. These include a urine sample and x-rays, and then blood to measure uterine tissue. Ending3: If the pregnancy wasn't planned, take her to the vet as soon as you find out she's pregnant. [substeps] If you plan to breed your dog, it's recommended that you wait until she's at least 24 months old. Ending4: [substeps] Urinary tract infections often cause breeding. During this point, the vet will ensure your dog does not have urinary tract infections.

Answer format: ending1/ending2/ending3/ending4