05/04/2026
Pregnancy Tells! 🐶🐶🐶🐶🐶🐶🐶🐶
One of the first and more quantifiable indicators is around when the potential puppies implant on the uterine walls.
If I keep a good photographic record of gum color, we should be able to see a noticeable difference around what should be day 21.
Key to seeing this is photographing in the same light and location at least once a day. Once you get closer to the approximate day 21, photograph in the morning and evening to see this fleeting indicator.
There is a noticeable difference when you see it!
Below are June Bug’s gums today and an images of my Wolfhound b*tches gum changes through this first trimester. You can clearly see a difference between E & D and the rest of the photos.
This is an anecdotal indicator that many breeders use. Here are some scientific views on why this may happen:
The Physiological Basis
While "pale gums" aren't a textbook symptom of canine implantation, there are two primary biological shifts occurring around that time (approximately 16 to 22 days after the LH surge) that provide a plausible explanation:
• Blood Volume Expansion: Early in pregnancy, a dog’s plasma volume begins to increase significantly to support the growing placental and fetal needs. However, the production of new red blood cells (erythrocytes) often lags behind this fluid increase. This results in physiologic anemia of pregnancy, where the Packed Cell Volume (PCV) drops. This can make mucous membranes appear slightly lighter than their usual vibrant pink.
• Localized Blood Flow Shifts: During nidation (implantation), the body undergoes complex hormonal shifts and a massive recruitment of blood flow to the uterine lining to support the developing embryos. Some breeders theorize that this "shunting" of blood to the reproductive tract can cause a transient, temporary drop in peripheral blood pressure or surface perfusion, leading to a brief period of paleness.
The "Nidation Dip" and Lore
In many breeding circles, this paleness is associated with a concurrent dip in re**al temperature, similar to the temperature drop seen right before whelping.
• The Theory: A brief surge in estrogen or a fluctuation in progesterone levels during the window when the blastocysts attach to the uterine wall may cause a temporary vasodilation or shift in systemic blood pressure.
• The Reality: Because this window is so narrow—often lasting only a few hours—and because "pale" is a subjective observation, it has remained largely in the realm of anecdotal evidence and "breeder’s lore" rather than clinical veterinary practice.
Clinical Considerations
It is important to distinguish this "implantation paleness" from clinical concerns. Because nidation happens roughly three weeks after breeding, the timing can overlap with other issues.