Determine Whelping Dates


The “Whelp Dates” is determined by counting 63 days from the date of ovulation. Ovularion occurs when the progesterone range is between 4 and 6 ng/mls (this may vary in some cases where progesterone “surges” or different test protocols between laboratories). The whelp date is estimated with a typical fluctuation of no more than +/- hours.

If LH testing is done, the Whelp Date is calculated at 65 days from a positive LH test result.

If a vaginal smear is done and show a jump from being “in season to “not in season” (cornflakes w/ nuclei g fried eggs w/ nuclei), the due date is 56 days from the “not in season” smear date.

If no timing was done and we are unsure of a due date, progesterone testing at the end of pregnancy is recommended to determine when the bitch will whelp.

If a c-section is not planned, the owner needs to monitor for temperature drop (3 times a day) and test progesterone level to make sure that we are not taking the puppies out too soon or put the mother and pups in a compromised situation by keeping them in too late.

Progesterone tests performed at the time of whelping are a good idea because the temperature might not always drop as low as desired. The amount of the drop depends on the size of the litter, (cases of only 1-2 puppies typically have smaller drops). This test is also recommended as it helps us estimate when she will deliver. And, in the end, it will cost less to the owner.

Ultrasound(s) or Radiograph(s) can help determine a whelp date if no other options are available.

Ultrasounds help the doctor to determine the age of the puppies and is easier to do around day 25 to 30, but it is possible to do it later.

Radiographs can help determine the calcification level of the puppies. If toes, or teeth are present on the radiograph, the bitch is expected to whelp within 1-3 days.

When it comes to bulldogs, it is always better to schedule and perform a c-section 1 day before estimated due date. This prevents putting the bitch in a compromised situation of natural whelping and having an emergency in the middle of the night.

Singlton cases (one puppy litters) are the most challenging to time whelping because it is the puppy that initiates labor, not the mother, If there is not enough stimulation in the uterus due to the decreased levels of hormones from only one puppy, the temperature might not drop and the mother will not go into labor.