This study was designed to identify the secular trend in the age at menarche and to investigate the possible factors that influence the age at menarche using representative Korean data from the 2005 Korean National Health and Nutrition Survey. Three thousand five hundred sixty-two women born between 1920 and 1985 were enrolled to identify secular trends in the age at menarche and 620 girls born between 1986 and 1995 were recruited to evaluate the factors influencing the age at onset of menarche. Mean age at menarche decreased from 16.90 +/- 1.25 years for women born between 1920 and 1925 to 13.79 +/- 1.37 years for those born between 1980 and 1985, indicating a downward trend of 0.68 years per decade (95% CI, 0.64-0.71) in age at menarche. Mean age at menarche of girls born between 1986 and 1995 was 13.10 +/- 0.06 years as estimated by the Kaplan-Meier method. Among girls born between 1986 and 1995, menarcheal girls had a larger waist circumference, a higher body mass index (BMI), and lower maternal menarcheal age and maternal age at birth than premenarcheal girls. The energy and nutrient intake of protein, sugar, fiber, ash, phosphate, natrium, thiamine, riboflavin, and niacin were greater for menarcheal girls than for premenarcheal girls. These data indicate a decreasing secular trend of age at menarche in a Korean population born between 1920 and 1995. Furthermore, maternal menarcheal age, BMI, maternal age at birth, and nutrition are important variables that appear to influence age at menarche in Korean girls.

No abstract

Among various reproductive factors, age at first birth was negatively associated with metabolic syndrome in Korean postmenopausal women.

An independent relationship exists between HOMA-IR and AMH in women without PCOS, possibly due to the effect of abnormal insulin action on AMH secretion by granulosa cells.

Chemotherapy and radiotherapy improved survival rates of patients with cancer. However, they can cause ovarian failure and infertility in women of reproductive age. Infertility following cancer treatment is considered a major quality of life issue. Ovarian tissue cryopreservation and transplantation is an important option for fertility preservation in adult patients with cancer who need immediate chemotherapy or do not want to undergo ovarian stimulation. Ovarian tissue freezing is the only option for preserving the fertility of prepubertal patients with cancer. In a recent review, it was reported that frozen-thawed ovarian transplantation has lead to about 90 live births and the conception rate was about 30%. Endocrine function recovery was observed in 92.9% between 3.5 and 6.5 months after transplantation. Based on our review, ovarian tissue cryopreservation and transplantation may be carefully considered before cancer treatment in order to preserve fertility and endocrine function in young cancer survivors.