The changes in the oral cavity can appear as consequences of some systemic diseases, but also of some physiological changes that appear during life, especially in women. One of those physiological changes is pregnancy which consequently with its increased secretion of gestational hormones estrogene and progesterone, can cause some pathological conditions and lesions in oral cavity such as periodontitis, gingivitis and pregnancy granuloma. Given that gingiva has receptors for both estrogene and progesterone, elevated levels of those hormones induces changes in oral cavity leading to a gingival supersensitivity to dental plaque. The inflammatory response which occurs from the infection from the periodontal pathogenes can result in unwanted pregnancy outcome, most common preeclampsia, preterm birth and reduced birth weight. Non-surgical periodontal therapy in pregnant women is harmless and should be applied without fear or prejudice, and most commonly includes dental X-rays, although radiation exposure is minimal, it is advised to wait with such diagnostics after the first trimester. Pregnant women should definitely go to check-ups that would include professional cleaning of dental calculus, tooth polishing and, if necessary, non-surgical periodontal therapy. If there is a need for antibiotic therapy the safest and best demonstrated have proved to be antibiotics from the penicillin groups, while tetracycline antibiotics are prohibited from using.