Menstrual cycles are a key driver of reproductive events in women, which is a physiological process and associated with the ability to reproduce. A period, or menstruation, marks the beginning of the process by which the uterus, or womb, prepares itself for pregnancy. Each month the lining of the uterus, called the endometrium, is shed from the body, producing a period, and a new lining is grow...

Background: Cigarette smoking is among the main preventable causes of untimely death, morbidity and mortality in the world. Various reasons have been suggested for cigarette smoking among students which are mostly related to the culture and customs of a country. This study aimed to evaluate the factors associated with cigarette smoking among students. Materials and Methods: This cross-sectional...

OBJECTIVE To compare the knowledge of contraceptive methods as well as to identify factors associated with adequate knowledge among public and private school adolescents. METHODS A cross-sectional study comprising 1,594 adolescents aged between 12 and 19 years old from 13 public and five private schools in the city of São Paulo city, Brazil, was carried out from June to December 2003. Schools...

Fifty years ago adolescents mostly died of natural causes, whereas they now die from more preventable causes. Part of this change has been a worldwide rise in adolescent suicide rates in both developed and developing countries. Suicides are probably under reported due to cultural and religious stigma attached to self-destruction. Objectives of this study were to collect data about suicidal thou...

Adolescent smokers tend to have peers who smoke, but it is unclear whether this arises from self-selection of smoking peers or whether this is a causal effect on the uptake of smoking (incident smoking). The authors used school tutor group current smoking prevalence, an unbiased measure of peer smoking in high schools in the United Kingdom, to estimate the independent effect of peer smoking on ...

OBJECTIVE Harm-minimization policies suggest that alcohol use is a part of normal adolescent development and that parents should supervise their children's use to encourage responsible drinking. Zero-tolerance policies suggest that all underage alcohol use should be discouraged. This article compared hypotheses derived from harm-minimization and zero-tolerance policies regarding the influence o...

Background: Globally, adolescent sexual behavior is a major health concern and the focus of many researches. However, negative attitude towards premarital sex and sense of community belonging have not been examined in relation to adolescent sexual behavior. The purpose of this study was to examine whether these two factors are associated with adolescent sexual behavior. Methods: We conducted a ...

Significant prevalence rates of adolescent scoliosis in China were suggested in previous studies. However, school screenings for adolescent scoliosis have been suspended due to low rates of positive detection under the past screening system in China. The present study was undertaken to screen for adolescent scoliosis in middle school students under a modern assessment system in a district of Sh...