Pregnancy in dogs is an intense physiological period lasting around two months on average. For a responsible owner, whether the pregnancy was planned as part of a breeding programme or came as a surprise, it is a time of heightened attention and special care. The mother-to-be’s body switches over to sustaining the litter and preparing for birth, and that calls for conscious support from the owner.
A sound understanding of the physiology, correct feeding and timely check-ups is essential for keeping both the bitch and her puppies healthy. This guide, prepared by the experts at Zviropolis, gives you the information you need on how pregnancy progresses, how it is diagnosed and how to prepare for whelping.
When can a bitch become pregnant, and what does it mean for her health?
Bitches usually reach sexual maturity between 6 and 12 months of age, although in giant breeds it can be as late as the second year of life. Maturity is signalled by the first heat (season).
It must be stressed, however, that the physiological ability to conceive is not the same as being physically and mentally ready for motherhood. Responsible breeders only mate a bitch once she has come through the turbulent phase of adolescence and reached her full adult size. It is generally recommended that a bitch be at least 2 or 3 years old, to protect her health and physical condition both before and after pregnancy. The right breeding age is crucial to the health of the mother and her puppies.
Pregnancy and whelping at a very young age carry enormous risks that can end in miscarriage or even the death of a mother who is simply too young. The foetuses may be too large for a physically immature bitch. Alongside age and physical and mental maturity, the decision to breed must also be conditional on good health and the absence of any diagnosed genetic disorders.
How long does pregnancy last in dogs, and how do you recognise it?
Pregnancy in dogs lasts on average 58 to 70 days, with a typical duration of around 63 days. Canine gestation can be divided into three trimesters:
- First trimester (weeks 0–3): The fertilisation and implantation phase. The embryos develop and settle into the uterus. The bitch may not yet show any visible signs of pregnancy. At this stage the embryo consists of blastomeres.
- Second trimester (weeks 4–6): Intensive development of the internal and external organs takes place, along with weight gain. The pregnancy becomes visible: the abdomen rounds out, and the mammary glands thicken and darken in colour.
- Third trimester (weeks 7–9): The foetuses gain weight and mature. They reach 70% of their birth weight and their bones harden. The mother gains 20–55% in body weight.
Watching for signs of pregnancy
Owners who have deliberately had their bitch mated watch her day by day, but the symptoms in the first trimester are non-specific: reduced appetite, mild tiredness and possibly vomiting.
The more telling, later signs are:
- Enlarged nipples: Within the first few weeks you may notice the nipples becoming more prominent and enlarged. Shortly before whelping, colostrum (the puppies’ first food) appears in the mammary glands.
- Enlarged abdomen: From around week 3–4 of pregnancy, the bitch’s belly begins to grow and becomes more rounded.
- Behavioural changes: Pregnant bitches may become more sociable or, conversely, withdrawn, seeking peace and seclusion. In the eighth week they become restless and start nesting.
Phantom pregnancy: a hormonal phenomenon
Exactly the same signs of pregnancy can be brought on by a phantom pregnancy (pseudopregnancy), a common phenomenon in unspayed bitches regardless of age or breed. Phantom pregnancy stems from hormonal imbalance, usually appears 3 to 12 weeks after a season and can last several weeks. It shows itself in behavioural changes (nesting, treating toys as offspring, irritability, aggressively guarding the “puppies”) and physical ones (swollen mammary glands filling with milk). A phantom pregnancy usually resolves on its own, but you should seek advice from a veterinarian. If your bitch suffers from the symptoms of phantom pregnancy, it is worth considering spaying.
Diagnosing pregnancy: tests and predicting the whelping date
Regular visits to the vet are essential for monitoring the bitch’s health and the progress of the pregnancy. At the clinic, a range of tests can be carried out to assess the condition of the mother and the litter precisely, and to estimate the whelping date.
Tests to confirm and monitor pregnancy
The key diagnostic tests, depending on the stage of pregnancy, are:
- Serological test (relaxin): A blood test measures the level of relaxin, a hormone secreted by the placenta from around the third week of pregnancy.
- Ultrasound scan: Possible from day 21 after mating, with day 25 or 26 being the optimal time. An ultrasound confirms that the puppies are alive and can detect foetal heartbeats as early as day 24–25. The method is safe and effective.
- X-ray: Possible no earlier than day 45 of pregnancy. X-rays are crucial because they allow the litter size to be determined by showing the number of spines.
- Palpation: Carried out between days 15 and 35 of pregnancy, but it requires a great deal of experience on the vet’s part.
Litter size cannot be predicted; it depends on the size, age and breed of the mother and father, their condition and their state of health.
Predicting the whelping date
One way of pinpointing the whelping date is to measure progesterone levels, which should be done every two days during the final week of pregnancy. A drop below 3 ng/ml indicates that whelping is fast approaching. In addition, rectal temperature is measured over the last few days of pregnancy; the day before whelping, core body temperature drops by 1°C (to around 37°C).
Optimal care for a pregnant bitch
A pregnant bitch needs not only medical monitoring but also the right support in everyday life.
Feeding and supplements
A balanced diet with adequate fat, sufficient calories and plenty of omega-3 fatty acids is key to the bitch’s health and the puppies’ development.
- First half of pregnancy: For the first four weeks, the bitch’s nutritional needs barely change.
- Second half of pregnancy: From around week 5, food portions need to be increased by roughly 10% per week, as the growing puppies need minerals, protein and energy. It is a good idea to offer smaller but more frequent meals, which makes eating easier for her, especially once the expanding uterus is pressing on the stomach.
- Important warnings: Under no circumstances should you overfeed the dog, as this can lead to difficulties during whelping. Because of the risk of postpartum eclampsia (hypocalcaemia, a calcium deficiency associated with lactation), calcium supplements are not recommended during pregnancy, only after whelping.
Exercise and environment
The bitch’s physical activity should be tailored to her condition. There is no need to restrict exercise in the first half of pregnancy; strenuous exertion should only be avoided in the second half. Light activity, such as walks at a moderate pace, can benefit her fitness and health.
Early on, it is worth setting up a quiet, comfortable resting spot for her, ideally in a peaceful corner of the house. Line it with soft materials that will give her comfort and a sense of security. Avoid unnecessary stress, which can have a negative effect on the pregnancy.
Preparing for whelping and how it unfolds
Preparing for the birth is a key stage in caring for your bitch.
Preparing the whelping box
It is worth setting up a dedicated whelping box (nest) in a particularly quiet spot and encouraging her to sleep in it. The space should feel safe and be lined with clean, soft materials that can be changed easily. You should also have clean towels on hand for drying newborn puppies, along with a disposable sterile scalpel blade in case the umbilical cord needs to be cut.
The stages of whelping
Whelping in dogs lasts from 3 to 24 hours, and occasionally as long as 36.
- Stage 1: Dilation of the cervix. The preparatory phase. The bitch stops eating, becomes restless and may urinate and defecate more often.
- Stage 2: Delivery of the puppies. The bitch has straining contractions as she pushes the puppies out. She licks each newborn puppy clean and bites through the umbilical cord.
- Stage 3: Passing of the foetal membranes. This follows a few minutes after the puppies are delivered. The bitch expels the foetal membranes (placenta) together with greenish foetal fluids. She will often eat the placenta.
Complications and when to intervene
Whelping should be supervised. Giving birth is hugely stressful for a dog, so do not disturb her, make noise or try to feed her.
Contact a veterinarian immediately if:
- No puppy has been born after six hours of contractions.
- The puppies are weak and the bitch is unable to care for them.
- The bitch is having difficulty giving birth.
There are many causes of a difficult birth; the most common are breeding bitches that are too young, breeding bitches with genetic pelvic defects, breeding overweight or obese bitches, and a high birth weight of the puppies.
If the pregnancy threatens the bitch’s health, a veterinarian can terminate it; terminating an advanced pregnancy usually requires surgery and should be combined with spaying, to prevent further unwanted pregnancies as well as pyometra.
Summary
Pregnancy in dogs is a complex but short period that calls for exceptional care and commitment from the owner. Proper feeding, veterinary check-ups and informed preparation for whelping are essential to the health of the mother and her puppies.
The golden rule for any sensible owner should be to prevent unwanted pregnancies through responsible breeding. And while you wait for the litter, it is worth learning about your bitch’s needs so that you can respond properly to any complications.
If you are planning an addition to the family, or have any concerns about the course of the pregnancy, feeding or whelping, do not hesitate to consult our specialists. We are here to support you at every stage of your bitch’s motherhood.
Frequently asked questions:
1. How long does pregnancy last in dogs?
Pregnancy in dogs lasts on average 58 to 70 days, with the standard time to whelping being around 63 days.
2. When is the best time to confirm a bitch’s pregnancy?
The first tests, such as an ultrasound scan, can be carried out around 21–26 days after mating to confirm the presence and viability of the foetuses. An X-ray, which shows the exact number of puppies, is only possible after day 45.
3. Can dogs have a phantom pregnancy?
Yes, phantom pregnancy (pseudopregnancy) is common in unspayed bitches regardless of age or breed. It stems from hormonal imbalance and can manifest as nesting, aggression and swollen mammary glands. If phantom pregnancies keep recurring, it is worth considering spaying.
4. How should a bitch’s diet change during pregnancy?
For the first four weeks the diet stays the same. Only from around week 5 should you gradually increase the calorie content of the food to provide energy for the growing foetuses, which means increasing portions by roughly 10% per week. Overfeeding and calcium supplementation before whelping must be strictly avoided, as they could lead to complications.
5. When is veterinary intervention needed during whelping?
Most births proceed naturally, but intervention is needed if:
- No puppy has been born after six hours of strong contractions.
- The bitch is having difficulty giving birth or is exhausted.
- The puppies are weak and the mother shows no interest in them.
