
Background: Menstrual problems account for much of the morbidity, affecting one in every five women during their life span. Thyroid dysfunction is associated with a range of menstrual abnormalities, including oligomenorrhea, amenorrhea, and menorrhagia. The aim of this study is to show the menstrual pattern in the studied women and to study the effect of thyroid disorders on the menstrual pattern among the affected women. Methods: A cross-sectional study was conducted in Northern Saudi Arabia. The study included160 randomly selected women from the general female population of Northern Saudi Arabia. A pre-designed online questionnaire which was distributed among the population. The questionnaire included the relevant questions to collect data about the socio-demographic characteristics of the participants, if the patient has menstrual disorders orthyroid disorders and their relation to each others. Results: Ninety three (58.1%) of the studied women had menstrual irregularity. Twenty one (13.1%) of the studied women had Hypothyroidism and only one case (0.6%) had Hyperthyroidism, 7.5% only of hypothyroidism cases had menstrual irregularity. There was a significant relationship between thyroid problems and menstrual irregularity and abnormal uterine bleeding (P< 0.05). Conclusion: These data demonstrate that hyperthyroidism in women is less frequently associated with menstrual abnormalities than was expected. Furthermore, There was a significant relationship between thyroid problems and menstrual irregularity and abnormal uterine bleeding (P< 0.05).