Ages at menarche and first birth are established risk factors for breast cancer. The interval between these ages may also affect risk, since the breast is more susceptible to carcinogenic insults during this period than during the parous period. However, few investigators have studied this relation. Using logistic regression, the authors evaluated associations between the timing of reproductive...

The breeding season was investigated in 174 female cats that were acclimated under a natural photoperiod, and determined the interval between birth and initial estrus (puberty) was determined in 125 cats. Although the breeding season differed noticeably among individual animals, the mean was 180.4 +/- 3.0 (SE) days between the end of January and the end of July. The interval between birth and f...

introduction & objective: considering the importance of reproductive health and in order to determine the knowledge of girl high school students about several aspects of reproductive health the present study was done. materials & methods: using cluster random sampling, 546 questionnaires were filled in eight high schools in shiraz. results: the results showed that these adolescents have accepta...

OBJECTIVES To test the contraceptive confidence hypothesis in a modern context. The hypothesis is that women using effective or modern contraceptive methods have increased contraceptive confidence and hence a shorter interval between marriage and first birth than users of ineffective or traditional methods. We extend the hypothesis to incorporate the role of abortion, arguing that it acts as a ...

the objective of this study was to investigate the effect of birth weight (bw) on future milk production and reproductive performance in iranian holstein cattle. records of holstein cows between 1967 and 2010 were obtained from the animal breeding center of iran. birth weights within each herd were grouped into five categories based on the standard normal distribution curves (z ≤-0.8416, -0.841...

the government of the united republic of tanzania has initiated the integrated management of childhood illness program to improve the health and wellbeing of children.tanzania's under-five mortality rate is still 1.7 times higher than the world average and, in order to achieve its millennium development goal 4 target, its annual reduction rate is quite low at 2.2. the main aim of the study is t...

BACKGROUND Ovarian hormones, parity and length of 'menarche-to-first birth' time interval are known risk factors for breast cancer, yet the associations between 17β-estradiol, progesterone and these reproductive factors remain unclear. METHODS A total of 204 women (25-35 years) who participated in the Norwegian EBBA-I study collected daily saliva samples for one complete menstrual cycle, and ...