There comes a time when many-a-worried dog owner may have to ask, “Is my dog pregnant?”. You might think the answer is a simple yes or no, but unlike humans, it can be difficult to gauge whether a dog is pregnant until the final few days of the pregnancy!
Typically, canine gestation is around 60-63 days long, beginning on the day of conception. Ideally you’ll want to know whether your dog is pregnant a few weeks in advance so you have time to prepare of course, but as we mentioned it can be difficult to spot. What makes matters more difficult is the fact that many females will experience pseudo-pregnancies, which are very similar to actually pregnancy – just without the pups!
If you think your dog is pregnant, but aren’t too sure, you can always confirm the pregnancy at your vet, see, ‘Detecting Canine Pregnancy’ below.
About the Canine Oestrus Cycle: When is Pregnancy Possible?
Like humans and other mammals, female dogs experience a cyclic period of fertility. Human females are typically fertile 12 times a year, experiencing monthly fertility cycles, whereas female dogs cycle only twice a year.
Each cycle of the canine oestrus cycle takes around 6 months, this means that a female dog is only fertile on average twice a year. Each fertile period lasts for around 21 days.
Dogs become sexually mature and able to conceive from between 8-18 months, although this number can vary wildly between breeds (and even within the same breed). Typically males will mature before females.
A single oestrus cycle can be split in to four distinct phases:
- Proestrus – Marks the start of being ‘in heat’ and lasts for around 9 days. During this phase, the female is not interested in advances by the males. Proestrus is usually accompanied by bloody discharge from the vagina. Copulation during this phase is unlikely to result in pregnancy, however canine sperm can last for up to 11 days in the uterine tract.
- Oestrus – The fertile phase of heat, marking the release of mature, female eggs. Oestrus lasts for up to 20 days. During this period, the female will stand to be mated and is interesting in the male’s advances. Copulation during this phase is likely to result in pregnancy.
- Dioestrus – During this phase, the female is subject to multiple hormonal changes – pregnant or not. These hormone changes can result in non-pregnant female dogs experiencing pseudo-pregnancies (also known as phantom pregnancies). Typically this phase will last for around 56-60 days in the pregnant female dog, although in non-pregnant bitches, dioestrus may last for up to 100 days.
- Anoestrus – This is the phase of the oestrus cycle where the female is non-fertile. This lengthy 4-5 month period makes up the bulk of the canine oestrus cycle.