The sexual cycle of a female has different phases: she accepts the male only during the peak, which occurs at the same time as blood loss, which, in the case of a Saint Bernard female can not go undetected.
  During the initial phase, however, the female does not accept mating. At approximately the 9th or 10th day, blood loss turns lighter in colour and tend to fade: be careful, heat is not finished! On the contrary, it is from this point on the female will search her mate.
  Fertile days are usually between the 10th and the 14th, counting from the first day of blood loss.

  If you planned a mating, especially if there is to be a long trip with your female to an interested stud, it would be best for her to have an examination at the vet to check her precise fertile days When the moment is right, it always better to keep an eye on the two partners and, if need be, help them, by sustaining the female to avoid trauma.
  In the kennel, females are usually put inside a labour department (as horses and cows) to avoid the excitement of the male, who would "chase" the female, jumping up and down every time she moves, sits down and so on.
  Aside from this practical advice, Saint Bernards usually mate in the most natural way: the breed is very "healthy" and their reproductive instincts are fair.
the need for artificial insemination is extremely rare.
  Important: with this breed it is of absolute importance to know the precise date of mating. If, at the end of pregnancy, the female does not give birth spontaneously, she must undergo a cesarean section: a day late could cost the life of both mother and puppies.

  Pregnancy lasts between 62 and 63 days. During the first month the female must maintain her usual rhythm of life.
  She can take walks and play as usual; feeding shouldn't change.
  At day 35, an expert veterinarian could tell you already if she is pregnant by palpation of the abdomen. Careful: diagnosis is easier at day 35 than in the following ones, because the foetuses start developing and are no longer small lumps easy to feel. If you want an early diagnosis, at the third week you could make your dog have an ultrasonogram, which can have another benefit: we could know immediately how many puppies we're expecting.
  During the second month of pregnancy the dog becomes fuller and her temperament can suffer changes: she could become lazier, "languid" and she will easily feel fatigue. You need to decrease gradually her physical activities and increase her food rations from a 15% (at the 40th day of pegnancy) to a 30% (when gestation is about to end).
  It is good to integrate food rations with products rich of calcium (milk, cheese) or add calcium in powder.
  There could be different signs the dog is about to give birth: all bitches start "preparing the nest" rasping and tearing to shreds with their teeth blankets, cloths and anything they can find. But whereas some do it when the time has already come, others begin a week earlier.
  The only certain sign the bitch is going to have the puppies within the following 24 hours is temperature lowering. The dog's temperature drops a lot below average: it turns abruptly from38-38,5 °C to 37-37,5 °C.
Prepare for the happy event and alert the veterinarian.

  About ten days prior to the "happy event" you must set a functional "delivery room", which could be as well a simple box of proper size, made of wooden boards.
  The inside of the delivery room must be absolutely smooth, with no wood or nails sticking out and without gaps between the boards: newborns are completely blind, but this won't stop them from snooping around the delivery room and getting into trouble... the first time they get the chance.
  The box should be provided with clothes and newspaper sheets in shreds, to avoid the possibility of a puppy being caught (and even suffocated) by an excessively large cloth. The bitch will, by rasping and tearing to shreds cloth and paper, certainly do her share of the work in preparing a secure "nest": but let's assure ourselves everything is really properly set.
  Keep at the ready extra clean cloth: the delivery room must always be extremely clean. Cloth employed during delivery will become useless, soaked in blood and amniotic fluid: when the puppies are born you must replace them with a single large and soft cloth, very tight and stretched in the corners, so that puppies don't end up under it. To fix it at the bottom of the box you could use a very strong bi-adhesive tape; better to avoid nails or clips, unless they could be applied from the outside.

  When birth begins, some females are happy to have their master by their side, while others make it clear they would rather be left alone. In that case we should respect her wishes... half way, don't breath on her neck and don't touch her: but absolutely stay around and keep the vet alert on the phone (better yet if present).
  When a Saint Bernard gives birth she should never be left on her own.
  If the female doesn't want us around, we will remain at a distance of no more than two or three meters; if she needs us we can sit next to her, pet her and hearten her, in particular if it's her first litter.
vIf everything goes well, between the time the water breakes and the birth of the first puppy there should be an interval of half an hour to one hour, whereas between one puppy and the next, in this breed, the interval could be rather long.
  If we notice the bitch is having trouble (either at the beginning of birth or between one puppy and the next) it is wise to make the vet intervene.
  Female Saint Bernards have frequent so-called "languid" births, with placental retention between one puppy and the next; in cases of very large litters, contractions could lose tonicity, or even cease, after the 5th or the 6th puppy. In these cases she'll need chemical stimulation and you'll have to perform an injection of the proper medicine.
  Examine the position of the puppies at birth: if the head is the first to come out with the front limbs stretched forward, everything is going well. The podalic position is acceptable, which does not imply major problems in dogs: but in very large dogs it could provoke difficulties. The worst case is when only the head comes out, without the front limbs (the puppy is carrying them stretched back or on the side, which could become a clog), or if only one leg appears: in this case, if the female's contractions won't succeed in expelling the puppy, she'll need the help of the veterinarian.
  If the puppy is born wrapped in the placenta, which the female immediately bites and swallows; she'll eat the placenta in this case too. This is perfectly normal and doesn't hurt the dog.
After breaking the placenta she'll start stimulating the newborn by licking him with energy to make the puppy breath: the puppy will probably react with a little cry, which is a sign of health and neonatal vigour. Some puppies do not cry at all: we shouldn't be worried, but observe if the puppy nudges his head to the side. If he does it means he is already searching for the breast: it means he's a vital but quiet little guy!
  As they are dried and stimulated, all puppies will turn towards the breast: if birth isn't still over and the mother is agitating there is the danger of squashing a puppy. Therefore, if we see she's paricularly nervous, it is best to group up the puppies in a separate box (being close they will keep each other warm and dry fast), waiting for the mother to be calm: even if they do not eat for a few hours they will be fine. The separate box should remain within the delivery box, so that the mother can keep an eye on her puppies: otherwise she will look for them desperately and become even more nervous.
  When the birth is over, the bitch is evidently uplifted: place the puppies next to her, check all of them are at her breast and let them suckle for approximately twenty minutes, then take them away (see the paragraph on "How to care for the litter during the first few days").
  At this point we can put the bitch on the leash and take her out to relieve herself: she will not want to come but we must insist. We can offer her some food (or better yet, a nice bottle of milk): if she refuses don't push her.
  The following day we'll check her body temperature: if it is above average call the veterinarian immediately.

  Unfortunately, it frequently happens among huge sized dogs that the mother unintentionally squashes her young.
  To avoid tragedy, you should always remove the puppies from the mother, after they are fed, and move them to small box near her. That way she can constantly keep an eye on them (otherwise she would desperately look for them). The box should be properly heated: the ideal solution are infra-red lamps, sold in almost any store.
  During the first fifteen days you should take the puppies to the mother every 2-3 hours, and every 4 hours from the sixteenth day onwards. You can leave them with the mother (under your supervision) for 15-20 minutes, and then remove them back to their "nursery".
  It is important to make sure that while they are fed every puppy has the same opportunity of being breast-fed. .