Unfortunately there is no difference between the symptoms of a false pregnancy vs. a real pregnancy. Some will even get milk. All the hormones are the same, but there is just no babies. If you want to be 100% certain she is not pregnant, you will have to wait until an ultrasound can be done about 5 or 6 weeks into pregnancy or wait a little longer and you will be able to feel the babies moving. You can spay during early pregnancy though, with minimal complications. You say this is her first heat, if she is really young or really small, you might want to at least consider this beings that you were going to have her spayed anyway.
I have had dogs tie with belly bands and diapers on, but I didn't have to wonder about the pregnancy because I saw the tie. He had his belly band up under his ribs and her diapers were just moved to the side! I no longer trust this method of preventing contraception! |