How to Tell If Your Guinea Pig Is Pregnant
📝 Summary
A pregnant sow gains weight fast, eats more, and her belly swells. Confirm by feeling for firm lumps (25+ days) or watching for a mating plug — though nocturnal chewing can hide it. Gestation is 68–75 days, so count ahead to the due date.
1 How to Tell If Your Guinea Pig Is Pregnant
Signs a guinea pig is in heat
A female in heat secretes a milky fluid from the vulva and grows restless and vocal for no clear reason; stroking above her rear excites her. In a mixed cage the boar will mount her.
A reliable sign is a mating plug — a milky plug the boar leaves after ejaculation to seal the vagina and raise mating success to about 85%.
But guinea pigs are nocturnal and mate at night, so plugs are passed then and the sow may eat them, leaving nothing to see by morning.
Signs of pregnancy
A plug means mating likely occurred and pregnancy is possible, but it too can be eaten. Weigh the sow instead: pregnant sows gain clear weight, eat more, and their belly grows — obvious later on. Feel the abdomen for small firm lumps; lumps mean she is at least 25 days along.
Tip: gestation is 68–75 days — calculate the due date early and prepare for the birth.
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