Detrimental Effects of Higher Body Mass Index and Smoking Habits on Menstrual Cycles in Korean Women.
Alteration of menstrual cycle by individual lifestyles and unfavorable habits may cause menstrual irregularity. We aimed to investigate the relationship between lifestyle factors and menstrual irregularity in Korean women using data from the Fifth Korea National Health and Nutrition Examination Survey (KNHANES) 2010-2012.



This cross-sectional study included 3779 nondiabetic Korean women aged 19-49 years who did not take any oral contraceptives or sex hormonal compounds. We examined the association of menstrual irregularity with age, body mass index (BMI), drinking experience, and smoking habits.



Age, Asian BMI, marriage status, age at menarche, and smoking habits were significantly associated with menstrual cycle irregularity (p < 0.01). The prevalence of menstrual irregularity was significantly increased at younger ages: 18.4%, 10.3%, and 10.5% at 19-29, 30-39, and 40-49 years, respectively. Moreover, obesity groups, defined as per Asian BMI using modified WHO criteria, were strongly associated with menstrual irregularity. BMI 25.0-29.9 [obesity class I] (adjusted odds ratios [OR], 1.94; 95% confidence intervals [CI], 1.37-2.74) and ≥30.0 [obesity class II] (adjusted OR, 2.18; 95% CI, 1.22-3.91) presented significantly higher risk of menstrual irregularity compared with BMI 18.5-22.9 [normal weight]. Multivariable analysis revealed that high BMI in younger women aged 19-29 years (p < 0.001) and smoking habits in middle-aged women aged 30-39 years (p < 0.005) significantly predicted menstrual irregularity.



This study substantiated that menstrual irregularity was closely associated with higher BMI and smoking habits in nondiabetic Korean women. Weight loss and smoking cessation should be recommended to promote women's reproductive health.
1 Department of Biomedical Laboratory Science, Graduate School, Eulji University , Seongnam-si, Gyeonggi-do, Korea.|2 Samkwang Medical Laboratories , Seoul, Korea.
An Na
AN
Jung
1 Department of Biomedical Laboratory Science, Graduate School, Eulji University , Seongnam-si, Gyeonggi-do, Korea.|3 Hankook Institute of Life Science , Seoul, Korea.
Ju Hwan
JH
Park
4 Department of Senior Healthcare, BK21 Plus Program, Graduated School, Eulji University , Daejeon, Korea.
Jihyun
J
Kim
5 Department of Obstetrics and Gynecology, Seoul National University College of Medicine , Seoul, Korea.
Seok Hyun
SH
Kim
6 Department of Obstetrics and Gynecology, Seoul National University Bundang Hospital , Seongnam-si, Gyeonggi-do, Korea.
Byung Chul
BC
Jee
1 Department of Biomedical Laboratory Science, Graduate School, Eulji University , Seongnam-si, Gyeonggi-do, Korea.
Byung Heun
BH
Cha
1 Department of Biomedical Laboratory Science, Graduate School, Eulji University , Seongnam-si, Gyeonggi-do, Korea.|4 Department of Senior Healthcare, BK21 Plus Program, Graduated School, Eulji University , Daejeon, Korea.
Jae Woong
JW
Sull
1 Department of Biomedical Laboratory Science, Graduate School, Eulji University , Seongnam-si, Gyeonggi-do, Korea.|4 Department of Senior Healthcare, BK21 Plus Program, Graduated School, Eulji University , Daejeon, Korea.|7 Eulji Medi-Bio Research Institute (EMBRI), Eulji University , Seongnam-si, Gyeonggi-do, Korea.
Jin Hyun
JH
Jun
D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008019:Life Style; D016015:Logistic Models; D008572:Menarche; D008599:Menstruation Disturbances / Q000453:epidemiology*; D008875:Middle Aged; D015999:Multivariate Analysis; D009749:Nutrition Surveys; D009765:Obesity / Q000453:epidemiology*; D016017:Odds Ratio; D060728:Reproductive Health; D056910:Republic of Korea / Q000453:epidemiology; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D055815:Young Adult
KNHANES; body mass index; menstrual cycle; reproductive health; smoking