Background: This study aimed to subjectively assess the changes in the oral health status of pregnant women, to find out their attitudes and knowledge about possible changes in the oral cavity that occurred during pregnancy, and their influence on the outcomes of pregnancy. Methods: 112 pregnant women who visited the Republican Siauliai Hospital during their pregnancy participated in the study. An anonymous self-administered questionnaire was used to conduct the research, surveying their demographic characteristics, oral health changes and habits during pregnancy, and awareness of possible negative pregnancy outcomes. Results: The study involved 112 pregnant women, with 35 in the first trimester, 28 in the second, and 48 in the third trimester. The findings revealed that pregnant women do not take sufficient care of their oral health: more than half of the respondents did not visit an oral care specialist during pregnancy; 22.3% of women reported brushing their teeth only once a day or less; and 35.7% did not clean interdental surfaces at all. Statistically, significantly more urban women believed there is a relationship between maternal oral health and adverse pregnancy outcomes than women living in rural areas (p = 0.013). While significant oral health changes were not observed in the first trimester, more women in the second and third trimesters reported issues such as bleeding gums, swelling, plaque accumulation, tartar, and caries (p < 0.001). Conclusions: The attitude of women towards oral health during pregnancy and their understanding of the possible risks for unfavorable pregnancy outcomes are insufficient. Notably, oral health issues become more prominent in the second and third trimesters, necessitating appropriate oral care to reduce the incidence of oral and dental diseases during pregnancy. This underscores the importance of educational and preventive public health policies focused on oral care for pregnant women, aimed at increasing awareness and promoting practices that safeguard both maternal and fetal health.