What it is
Reproduction depends on several systems working in step. Hormones from the brain and from the ovaries or testicles set the rhythm of heat and the making of sperm, the reproductive tract has to be open and healthy, and the whole dog needs to be in good shape. A problem anywhere along that path can mean a missed heat, a mating that leads to no puppies, or a pregnancy that is lost.
Some causes are inherited or linked to build, others are acquired: infections, cysts, thyroid and other hormone problems, injuries, or simply age. Males can be affected too, through changes in the testicles or the prostate.
In a dog that is not meant to have puppies, many of these changes go unnoticed. One matters in every unspayed female: an infection of the womb in the weeks after a heat, which can make her seriously ill quickly. A simple calendar of heats helps you see when something is off.
Signs you may notice
- Irregular or missing heats
- No pregnancy after mating
- Unusual vaginal discharge
- Drinks more and seems listless
- Swollen or uneven testicles
- Licks the genital area more
You may notice that a female's heat cycles become irregular or stop, that she does not conceive despite mating, or that there is unusual discharge from the vulva. Unusual discharge together with listlessness or increased thirst is a reason to see a vet without delay.
When to see a vet
Discharge together with listlessness, great thirst or a swollen belly in the weeks after a heat means a vet is needed immediately. Book a visit for irregular heats or a female that does not conceive.
This is general information, not veterinary advice. For your own dog's health, tests and treatment, see a vet.