Signs of pregnancy in guinea pigs -

https://guineapigsandy.com/all-about-guinea-pigs/breeding/signs-of-pregnancy-in-guinea-pigs/ After the mumps has been successfully covered, its behavior will remain the same for some time.

The first sign of pregnancy may be the absence of the next estrus about 16 days after mating, but an experienced pig breeder will be able to notice an enlarged tummy and feel the fetuses only in the third week of pregnancy.
You can determine pregnancy at such an early stage as follows: place the pig with your front paws on the table, grab the pig from the back with your hands on both sides of the abdomen. In this case, the thumbs should be on the back, and the other four should be under the stomach. Press gently on your tummy with your fingers. Stop the pressure if internal organs begin to be felt or if the mumps resists. You will be able to continue your examination after a short break. After a while, you will learn to distinguish between the internal organs of the mumps: the kidneys (just under the ribs, usually only the left kidney is felt), the intestines (you can feel the droppings lying in a string of beads :)) and the embryos. Examine the abdomen carefully along its entire length from the ribs to the pelvic region. With a little practice, you will be able to recognize fetuses at the earliest stages of pregnancy,starting from 3 weeks, when their size is no more than a small coin. To the touch, they resemble balls of water, lying in a row on each side of the abdomen. Be careful and try not to put too much pressure on your stomach!
In the fourth week of pregnancy, the embryos are clearly distinguishable and separated from each other, and you can try to guess the number of fetuses. However, in most cases, it is easy to get it wrong. If you can’t feel the fruit, alternatively try weighing your mumps regularly (say once a week). Although in the first two weeks the weight remains practically unchanged, starting from the fourth week it grows rapidly depending on the number of fruits. The mumps will gain weight throughout the pregnancy. Any weight loss at this stage is a sign of a disease caused, for example, by toxicosis or fetal death.
Starting from the fifth week, the pig will get fat more and more every day. You can transplant a male, however most females prefer to be in company and feel better if kept with other gilts (regardless of gender).
In the seventh week after conception, the movements of the fetus can be recognized, every day more and more clearly. Towards the end of pregnancy, you will probably be able to notice the movement of the small legs and hear or feel the small piglets chewing. A pig during this period can become incredibly large if it bears numerous offspring. Fruit weight can reach 50% of the female’s weight! It is now imperative to transplant the males if postpartum fertilization is undesirable. Females will be grateful to you for the opportunity to be alone with yourself.
After about 9 weeks of pregnancy, the birth canal begins to open. This can be seen in the pelvic area: the syphysis – the place where the two parts of the pelvis converge – begins to expand. This opening occurs 24-48 hours before delivery and is 1-2 fingers wide. To feel the pelvic region expand, place your finger directly in front of your vagina. If you are unsure, try comparing the mumps to other females.
At the end of pregnancy, the pig will become very limited in movement, and it will be extremely reluctant to move, but it must have a good appetite, otherwise the likelihood of developing toxicosis is not excluded.
Pregnancy in guinea pigs lasts approximately 10 weeks, or 67-72 days. Childbirth occurs earlier if the pregnancy is multiple. Sometimes in the literature you can find a period of 52 days, but in our opinion, piglets born earlier than 65 days later are underdeveloped and have little chance of survival.
Such a long gestation period is common in rodents and is explained by the fact that newborn piglets must be fully developed and able to escape from enemies, since pigs, unlike rats and mice, do not build underground burrows where the cubs could hide until they grow up and completely will not take shape.