Received August 23, 2024
Accepted June 02, 2025

Objective: To explore the knowledge concerning the impact of age on fertility in Thai women among fertile and subfertile women. Methods: A cross-sectional study was conducted at Maharaj Nakorn Chiang Mai Hospital, Thailand. The questionnaires consisted of sociodemographic questions and knowledge pertinent to the impact of age on fertility. Both fertile and subfertile women completed the same questionnaire anonymously. Results: A total of 500 women were included in the study, with two hundred and fifty in each group. The majority of women in both the fertile and subfertile group correctly identified the most fertile age of women (84.8% vs. 84.4%, P = 0.902) and the impact of age on infertility treatment (73.2% vs. 84.0%, P = 0.003). However, only one-fifth of the participants in both groups correctly identified the age that their fertility starts to decline, show a marked decline and ends. Most women in both groups chose the answer that overestimates their fertility potential. Moreover, 10.8% of subfertile women believed that fertility is not dependent on age and 16.0% believed that age does not affect the success rate of infertility treatment. Conclusion: The overall knowledge of women regarding the impact of age on fertility is relatively poor with no difference between fertile and subfertile women. These findings may indicate an urgent need to increase this area of knowledge in the population.