West Asia Organization for Cancer Prevention (WAOCP), APOCP's West Asia Chapter. Asian Pacific Journal of Cancer Prevention 1513-7368 14 9 2013 09 01 Reproductive Risk Factors for Thyroid Cancer: A Prospective Cohort Study in Khon Kaen, Thailand 5153 5155 28090 EN Journal Article 1970 01 01 <b>Background:</b> Because of the gender disparity in the incidence of thyroid cancer, this study aimed to determinethe association between reproductive factors and thyroid cancer. <br/><b>Methods</b>: A total of 10,767 eligible women fromthe Khon Kaen Cohort, recruited and interviewed between 1990 and 2001, were followed up until 2011. Thedata were linked to the Khon Kaen Population-Based Cancer Registry to detect thyroid cancer cases. <br/><b>Results</b>:There was 17 thyroid cancer cases detected, an incidence of 11.2 per 100,000 person-years, of which 70.6 % werepapillary tumors. The incidence was apparently greater among those with an early age of menarche, nulligravidawomen, and oral contraceptive users. Conlusions: There was a trend for thyroid cancer to develop in relationto longer estrogen exposure. This evidence is inconclusive but warrants further investigation. https://journal.waocp.org/article_28090_7d5839aedea329e143d7dca6965bf51a.pdf