The ages at which females establish marital union and give first birth depend on and result in varying demographic features. Utilizing the Ethiopian Demographic and Health Survey Data, this study examined determinants of first birth interval. The analysis was made using Cox proportional hazard model and Kaplan Meier plot based on data collected from 10,240 ever-married women in the age group 15...

1. Fertility is an important fitness component, but is difficult to measure in slowly reproducing, long-lived animals such as chimpanzees (Pan troglodytes). 2. We measured fertility and the effect of measured covariates on fertility in a 43-year sample of birth intervals of chimpanzees from the Gombe National Park, Tanzania using Cox proportional hazards regression with individual-level random ...

per birth interval were those published for the following interval (eg, 2005 estimates used for 1996e2000 births). Results From 1986 to 2000, 321 DBMD males resided in an MD STARnet site during one or more birth intervals, which produced a prevalence of 1/5000 residents. Race/ethnic-specific prevalence tended to be higher for Hispanics than non-Hispanic whites or African-Americans. Prevalence t...

Birth interval is a major determinant of rates of fertility, and is also a measure of parental investment in a child. In this paper the length of the birth interval in a traditional African population is analysed by sex of children. Birth intervals after the birth of a boy were significantly longer than after the birth of a girl, indicating higher parental investment in boys. However, in women ...

Pairs of first and second births and pairs of second and third births to the same Norwegian mothers were studied to determine the association between interpregnancy interval and birth weight, stillbirth, and neonatal death. Use of the pair approach provides one birth which could possibly have been affected by the length of the interval and one birth which could not. The association of interval ...