Indigenous populations living in villages in Brazil have presented high total fertility rates (TFR) that have increased over time in some cases. Meanwhile, data from the Brazilian Institute of Geography and Statistics (IBGE) or National Census Bureau show a decline in the TFR for the total self-declared indigenous population (combining urban, rural, and specific rural residence). The current st...

The large post-reproductive life span reported for the free-living hermaphroditic nematode, Caenorhabditis elegans, which lives for about 10 days after its 5-day period of self-reproduction, seems at odds with evolutionary theory. Species with long post-reproductive life spans such as mammals are sometimes explained by a need for parental care or transfer of information. This does not seem a su...

This is an endeavour to study the plausible causal relationship between cultural factors and human fertility in a more or less non-industrial rural population (schedule tribes) in Orissa, an Eastern Indian state. The bivariate and multivariate statistical analyses showed that lower level of child loss showed significant association with lower fertility. Other categorical variables such as highe...

Fertility impairments among men treated during childhood for cancer are known to occur after some, but not all, types of anti-cancer therapy. This is the first study to evaluate proven fertility among adult male survivors of childhood acute lymphoblastic leukemia (ALL). In a retrospective cohort study, proven fertility (ever fathered a pregnancy) was evaluated by self-report among 213 men treat...

Recent authors have reported a relationship between women's fertility status, as indexed by menstrual cycle phase, and conservatism in moral, social and political values. We conducted a survey to test for the existence of a relationship between menstrual cycle day and conservatism. 2213 women reporting regular menstrual cycles provided data about their political views. Of these women, 2208 prov...

Researchers and clinicians at Marquette University developed a method of Natural Family Planning (NFP) that utilizes self-monitoring of cervical mucus along with an electronic hormonal fertility monitor (EHFM) as a double check for the beginning and end of the fertile phase of the menstrual cycle. The EHFM is a hand held device that reads a threshold level of urinary metabolites of estrogen (es...

Heritable changes of phenotype arising in plant ontogenesis by the influence of environmental factors belong to the most intriguing genetic phenomena. An unusual inheritance pattern was detected during examination of male fertility restoration in the CMS-inducing "9E" type cytoplasm of sorghum: Rf-genes were functional in self-pollinated progeny of F(1) hybrids yet were either not expressed or ...

BACKGROUND We investigated coping strategies and communication strategies as predictors of fertility problem stress 12 months after start of fertility treatment. METHODS We used a prospective, longitudinal cohort design including 2250 people beginning fertility treatment with a 12-month follow-up. Data were based on self-administered questionnaires measuring communication with partner and wit...

Homothallism (self-fertility) describes a wide variety of sexual strategies that enable a fungus to reproduce in the absence of a mating partner. Unisexual reproduction, a form of homothallism, is a process whereby a fungus can progress through sexual reproduction in the absence of mating genes previously considered essential for self-fertility. In this study, we consider the molecular mechanis...