Pregnancy in Dogs
Written by Shula Berg BVSc CertAVP(GSAS) GPAdvCert(SASTS) MRCVS
Clinically reviewed by Elizabeth McLennan-Green BVM&S CertAVP(SAM) MRCVS
Table of Contents
Female dogs can get pregnant from their first season, usually around 6-9 months of age. Pregnancy lasts an average of 63 days (nine weeks); however, this can vary from 56-72 days. Release of the egg can be difficult to predict, and sperm can survive for several days, so the date of mating is not necessarily the date of conception. Timing from hormone measurement is much more accurate, but pregnancy length can also vary with both breed and litter size, with larger litters having shorter gestations. A female dog can also get pregnant from a “slip mating”, where there is no tie, so un-neutered male and female dogs should not be left unsupervised unless breeding is intended.
Much like in people, ultrasound is the best way to diagnose pregnancy. It is simple to perform and non-invasive, so there is minimal to no risk for the puppies. It is recommended to wait until four weeks post mating to perform ultrasound to increase the chance of accurate diagnosis. Before this time, foetal heartbeats are not visible so it can be difficult to distinguish pregnancy from normal fluid in the uterus. It is not possible to determine the number of puppies present on ultrasound.
X-ray can be used to confirm pregnancy once the foetal bones start to calcify, around day 42. X-ray can be used to confirm the number of puppies present but has some risk to both mum and babies, so is not recommended for pregnancy diagnosis. X-ray is mostly used during whelping if it is suspected that not all puppies have been delivered.
During the first six weeks of pregnancy, the dog’s energy (calorie) requirements do not change. She should be fed a normal, high quality complete dog food. Weight gain should be minimal, as increasing weight during this early period can cause more difficulties during whelping.
During the last three weeks of pregnancy, the puppies’ growth speeds up. This means they require a lot more energy, and the space for the stomach reduces. At six weeks of gestation the dog should be changed to a high-quality puppy food (over the course of a few days to avoid stomach upset). Puppy food has increased levels of protein and calcium to help support growth. It is also high energy, meaning a lower volume is required to meet requirements. Puppy food should be offered in several small meals, or available all day, with the amount offered increased by roughly 10% each week for the last few weeks of pregnancy. It is still important to avoid the dog putting on excess body fat, so if in doubt check with your vet or nurse.
Ideally, all female dogs should be fully vaccinated before getting pregnant. This is important as immunity is passed from mum to pup to protect them for the first eight weeks of life. If your dog is pregnant and not vaccinated, speak to your vet immediately. Not all vaccines are safe to be used during pregnancy, and some can only be given at certain points. Often, your vet will need to check the manufacturer’s guidelines.
Regular flea and worming treatment are important during pregnancy, as some parasites can be passed to the puppies before they are even born. A specific worming protocol in the final few weeks of pregnancy is often recommended to prevent this transmission to the puppies. Not all flea and worming treatments are safe to use during pregnancy, so it is important to speak to your vet or nurse, and not just give any products you already have.
During the first six weeks of gestation your dog can be walked as normal. It is advisable to avoid high energy exercise such as agility or working, especially as any accidental impact to the abdomen may be harmful. In the final weeks of pregnancy, exercise will likely drop off. Short walks are reasonable if the dog can manage, however, her energy requirements will increase and her mobility will reduce, so don’t force her to walk if she isn’t able or willing.
As your dog’s due date gets closer, consider where in the home you will accommodate her and the puppies. This should be somewhere quiet, away from small children and busy family life. It needs to be a comfortable temperature, draft free but not too hot, and should be a safe place for once the puppies start exploring. It is recommended to create a nest here a few weeks before whelping is expected and encourage the dog to use this as a safe place. Ideally, this needs to have enough space for mum to move around, and low sides to stop puppies rolling out. Commercial whelping boxes can be bought online, these include bars at the edges to help prevent the dog inadvertently crushing the puppies. A flat piece of bedding is ideal, such as vetbed, but avoid piles of blankets as these can easily suffocate puppies if left unattended.
Breeding can be costly, especially if intervention is needed during whelping such as a caesarean. Your vet will be happy to give you an idea of potential costs to ensure you are prepared for all eventualities.
Please note that the content made available on this webpage is for general information purposes only. Whilst we try to ensure that at the time of writing all material is up to date and reflects industry standards, we make no representation, warranties or guarantees that the information made available is up to date, accurate or complete. Any reliance placed by yourselves is done so at your own risk.
Page last reviewed: 16th January 2024
Next review due: 16th January 2026