Why Do Dogs Go Back-to-Back When Mating



Dogs, just like any other animal, are driven by instinct. One of those instincts is the instinct to mate. Some dogs may never get the chance, as long as they are kept close to home and there are no available partners to mate with. Some, through random chance or intentional breeding, may have the chance to procreate with a willing partner.
But something happens in dogs and other canids like wolves and coyotes during mating. They appear to become “stuck.” What is that back-to-back phase of mating? Why does it happen? Why do some dogs appear distressed by it? Are they okay or should I intervene?

The Root of the Behavior

Dogs, wolves, coyotes, jackals, and foxes, as members of the canine family, all share the same behavioral traits when it comes to mating: they are generally monogamous—meaning they have only one partner, and they have what is called a copulatory tie. This is the “tie” that happens after a dog mates.
The part of mating when the male mounts the female is only part of the process. During copulation, the male’s penis swells while the female’s vulva contracts. One feature, in particular, called the bulbis glandis, at the base of the penis, expands up to three times wider than normal. The female’s vaginal muscles lock down around this feature, effectively trapping the male until the mating process completes. The pair won’t be able to separate until the male’s tissue has shrunk and the female’s muscles relax. This can take up to 40 minutes but usually completes within 15 to 20.
It is believed that during this lock, the male may still ejaculate up to 30mL of seminal fluid, even though most of the male’s ejaculate is released during the initial phase of intercourse. Veterinarians and scientists aren’t completely sure why dogs and canines end up stuck back-to-back. It may be to help ensure the success of the mating. Even still, it is possible for the mating to fail and the female doesn’t become pregnant. The reverse is also true; a female can become pregnant even if the tie doesn’t occur.
A female’s heat cycle consists of two parts. The first part, when she emits pheromones, signifies to nearby males that she will be fertile soon. She will also start to bleed vaginally. During this phase, she won’t be receptive to any males, and she won’t be fertile. During the second phase, about seven to 10 days after the first phase, the vaginal discharge becomes less bloody and she will be more receptive to mating. Ovulation occurs around 11 days into her heat cycle. A male’s sperm can live inside the female for up to nine days. As long as some period of the female’s ovulation and the male’s live sperm coincide, pregnancy is likely.

Encouraging the Behavior

If you are breeding your dog, rest assured that the back-to-back stage of mating is completely natural. Even if one or both dogs seem distressed, they are alright and not in any pain. Never try to separate them once they’re “tied” together, even if it’s an unwanted mating, as you may harm them. If your dog has mated with a stray, or the mating wasn’t anticipated or wanted, consult a vet as soon as possible to avoid having a litter of puppies on your hands. And always try to prevent unintentional mating by keeping females in heat secluded during their heat, and spay or neuter your pets when they reach maturity and your vet allows it.
If you are considering breeding your dog, you should make sure to do your research ahead of time, and find a reputable breeder. Also, stick to breeds that are the same or very similar to your own dog. Some combinations and mixes are more common or appropriate than others. A great example is the Labradoodle, is a cross between a Labrador and a Poodle. Some mixes should not be attempted for the safety and health of your dog. For example, breeding a large male with a smaller female may result in birth complications. Never breed siblings or relatives. In-breeding can occur and may result in complications, deformities, and even death of the puppies. 

Other Solutions and Considerations

Before you decide to breed your dog, also consider your motivation and your dog. There are an estimated 70,000 puppies born in the US alone every day. Between six and eight million cats and dogs enter animal shelters every year, and approximately four to five million cats and dogs are euthanized every year. Around 61 percent of all dogs that enter an animal shelter are euthanized. The cost on taxpayers to impound, shelter, euthanize, and dispose of homeless animals is around two billion dollars every year.
Additionally, if you have a female and are considering breeding her, consider her health and happiness. Some dogs are never quite the same after having a litter of puppies. Having puppies isn’t only physically demanding for her, it’s also emotionally intense. The instinct to care for and protect their young is strong. She probably won’t enjoy having her babies taken away from her. She may become depressed, and her personality may even change after having puppies. 


Mating is a totally natural thing that all canines have in common. Like any other animal, the instructions are written into their DNA, and generally require no human intervention. Even when they look like the pushmi-pullyu from Doctor Doolittle, everything is fine. But breeding your dog may not be the best choice, especially considering how many animals are abandoned or surrendered to shelters every year. If you’re looking to acquire some puppies, check your local shelter or contact a rescue organization.