Managing Your Dog’s Pregnancy

The average gestation period for a female dog is 63 days from the day of mating, with a possible variation of plus or minus one week.

1. The Course of Gestation

Fertilization between the egg and sperm takes place in the oviduct (the end of the uterine horns).

Around day 11, the embryos penetrate the uterine horns.

They are then bathed in uterine milk until they attach to the uterine wall, via the placenta, around day 16: this is implantation.

The embryos then continue their development in the amniotic sac, connected to the mother by the umbilical cord.

Fetal growth intensifies particularly during the last third of gestation, between days 45 and 60.

Bone Development

Ossification begins around day 42

Ossification becomes clearly visible from day 50

2. Role of Hormones

Progesterone, secreted by the corpora lutea (ovarian follicles after ovulation), maintains the pregnancy.

The placenta also produces several hormones, including relaxin, which is essential for the relaxation of the peri-pubic tissues in preparation for whelping.

⚠️ Progesterone levels remain high in female dogs, whether pregnant or not: therefore, measuring progesterone levels cannot confirm pregnancy.

Why perform a pregnancy diagnosis?

Pregnancy diagnosis offers several major advantages:

-Confirming pregnancy

Allows us to distinguish between:

a truly non-pregnant female,

an early abortion,

a complete absence of pregnancy.

– Estimate the number of puppies

Adjust feeding at the end of gestation

Anticipate the risks of dystocia (difficult birth)

Detect the risk of singleton syndrome: a single puppy may continue to grow excessively, leading to a lack of oxygen and nutrients via the placenta, which can result in death in utero.

– Monitor proper development

Detect embryonic resorption

Identify growth abnormalities

Check fetal viability

Diagnostic Methods

1. External Changes

Abdominal enlargement: from the 4th week

Abdominal ptosis (dropped abdomen) at 2 months in the case of a large litter

Mammary development: from 25 to 30 days

Swollen and engorged mammary glands

Visible umbilical cord
⚠️ Unreliable as it is also present in cases of pseudopregnancy

Serous or whitish vaginal discharge around 25–30 days

Infrequent

Does not indicate pyometra

When present, it is highly suggestive of pregnancy

2. Abdominal palpation

To be performed very gently: rough or repeated manipulation can induce abortion.

From day 21: Embryonic ampullae (oval shapes) can be perceived.

After day 35: The ampullae become large and merge → difficult to distinguish individually.

From day 45: Fetal bone landmarks become palpable again.

3. Auscultation

At the end of gestation:

Fetal heart rate: 220 to 240 beats/minute

This method is particularly useful in cases of post-term pregnancy or during parturition.

More difficult in large breeds.

Portable Doppler devices can detect the fetal heartbeat, but a common mistake is to confuse the fetal heartbeat with the flow of the maternal aorta.

4. Abdominal ultrasound (preferred examination)

Ultrasound is the most reliable and comprehensive method.

It allows for:

Early diagnosis

Assessment of fetal viability (visualization of heartbeats)

Detection of embryonic resorption

Estimation of the number of puppies

Monitoring of growth

📅 Recommended timing:

21 to 25 days after ovulation

or 20 to 23 days after mating

Without precise heat monitoring, it is advisable to wait 25 days post-mating to avoid a false negative.

5. Relaxin Blood Test

Relaxin is currently the most specific hormone for pregnancy in female dogs.

Secreted by the placenta from the 3rd week

Independent of the number of puppies

Two blood tests available

⚠️ Test can be performed from the 3rd week, but it is preferable to wait 25 days to limit false negatives.
In case of an early negative result, repeat the test one week later.

Limitations:

Does not indicate the number of puppies

Remains positive even in case of abortion

6. Abdominal X-ray

A late examination, useful for:

Precisely determining the number of puppies

Checking skeletal mineralization

📅 Visible from 45 days (beginning of mineralization).

In practice, X-rays are taken during the last week of gestation.

Contrary to popular belief, radiography cannot predict whether a puppy will be able to pass through the birth canal, except in cases of major developmental abnormalities.

 

References : Centrale Canine

When will the puppies be born?

Several signs indicate that whelping is imminent. It’s important to be aware of them to calmly prepare for the arrival of the puppies.

Precursors

1️⃣ Drop in rectal temperature

This is a reliable indicator, provided it is monitored correctly.

Take the temperature morning and evening during the last days of gestation.

In the 24 hours before whelping, a drop of about 1°C is observed.

This drop is temporary (12 to 20 hours), so it’s important not to miss it.

2️⃣ Onset of lactation

The mammary glands begin to enlarge from the second month of gestation.

Their development is at its maximum about one week before whelping.

In:

First-time mothers (first litter): milk production generally occurs within 24 hours before whelping.

For women who have given birth before: colostrum can be present up to a week prior.

3️⃣ Vulvar swelling

The vulva gradually swells in the days leading up to delivery.
In first-time mothers, this sign may be subtle and appear only a few hours beforehand.

4️⃣ Cervical discharge

A clear, translucent, and colorless discharge appears at the vulva.
This is the latest sign, appearing just before the onset of labor.

 

How does whelping occur?

Whelping takes place in two main phases.

🔹 1. Preparatory Phase (Dilation)

Duration:

2 to 10 hours on average

Up to 36 hours in a first-time mother

Behavior:

Restlessness, anxiety

Searching for a quiet place to “make her nest”

Refusal to eat

Rapid panting

Sometimes vomiting

During this phase:

Uterine contractions begin.

They are involuntary and intermittent.

There are no visible abdominal contractions yet.

The cervix gradually dilates.

⚠️ It is essential not to stress or disturb the female dog. Stress can delay or stop whelping.

🔹 2. Expulsion Phase

Duration:

Generally less than 12 hours

Up to 36 hours in a first-time mother

Characteristics:

Uterine contractions are accompanied by visible abdominal contractions.

The first puppy often takes the longest to be born (up to 6 hours after the start of labor).

The average interval between births is 10 to 60 minutes.

At birth

The puppies are enclosed in the amniotic sac:

It usually ruptures during expulsion.

Otherwise, the mother opens it immediately after birth.

If the sac remains intact and the mother does not intervene, you must rupture it within 2 minutes so that the puppy can breathe.

The mother:

Licks the puppy (respiratory stimulation)

Cuts the umbilical cord with her teeth

A few minutes after each birth, the placenta is expelled.

Contractions then become less frequent until the next puppy is born.

Preparing for Whelping

Planning ahead allows you to experience this moment more calmly.

Prepare:

A quiet place, sheltered from drafts

A suitable whelping box

Sufficiently high sides

Anti-crushing bars for large breeds

A clean blanket

An infrared lamp (ideal nest temperature: 28 to 30°C)

Clean towels

A thermometer

Disinfected scissors

Disinfected thread

Betadine®

The female dog must remain calm.
Your role is primarily to observe. Intervention is generally not necessary.

What to do if needed?

Should the umbilical cord be cut?

Normally not.

If after 15 minutes the mother has not severed it:

Tie it off with disinfected thread about 2.5 cm from the navel.

Cut approximately 1.5 cm after the ligation.

Disinfect the stump with Betadine®.

What to do if a puppy isn’t breathing?

Clear the airways (using a bulb syringe or nasal aspirator).

Rub the chest vigorously with a warm, dry cloth to stimulate breathing.

In most cases, this stimulation is enough to trigger breathing.

Green discharge: Is it normal?

Yes.

The green color is a pigment from the placenta.

It is normal during labor.

When to call the veterinarian?

Contact your veterinarian if:

The gestation period exceeds 65 days

More than 2 hours pass between puppies

Green discharge appears and no puppies are born within 6 hours

Your dog seems to be in abnormal pain (whining, heavy bleeding, lethargy)

The number of puppies delivered is not the expected number and contractions have stopped for 2 hours

After whelping: foul-smelling discharge (risk of uterine infection)

After whelping: trembling, rapid breathing, restlessness (suspected eclampsia).

 

Puppy Monitoring

Birth doesn’t mark the end of monitoring; quite the opposite. The first few days of life are a particularly fragile period where the breeder’s attention is essential.

🌡️ Temperature Control

Puppies don’t regulate their body temperature properly at birth. It is therefore essential to keep them warm and monitor their temperature regularly.

Physiological Reference Points:

At birth: approximately 35.5°C (95.3°F)

During the 1st week: approximately 36.5°C (97.5°F)

Around the 3rd week: approximately 38°C (100.4°F)

Hypothermia can quickly lead to weakness, refusal to nurse, and endanger the puppy’s life.

 

⚖️ Feeding and Weight Gain

Feeding must be carefully monitored from the very first hours:

Check that each puppy is nursing properly.

Make sure that none are left out.

Monitor the mother’s milk production.

Daily weight gain is a key indicator of good health.

➡️ Puppies should be weighed daily at the same time, and their weights recorded to track their progress.

A lack of weight gain, or even weight loss, should be a cause for immediate concern.

We will discuss feeding, monitoring, and neonatal care in detail in the next chapter.

 

References: Dr. Charlotte Renard’s blog, veterinary consultant for Direct-Vet

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