"age of fertility" is a correct and usable phrase in written English.
It refers to the age at which a person is biologically able to bear children. Example: The average age of fertility for women has been steadily increasing in recent years, with many choosing to delay starting a family until their late 20s or early 30s.
"For most species, it doesn't make ecological sense to support females beyond the age of fertility, but elephant matriarchs are repositories of collective knowledge," Turkalo said.
The city has a number of demographic peculiarities stemming mainly from the effects of World War II; there are more women than men, and a sizable proportion of the female population is past the age of fertility.
When statistics show a rise in the total fertility rate over a given period, for example, cohort analysis may reveal that this results from a lowering of the cohort mean age of fertility rather than simply a rise in the cohort total fertility rate.
Mean age of fertility μ is calculated from Eq. (3).
Differences by mean age of fertility are present, but relatively small.
Analytically, Eq. (10) allows a simplified projection in terms of life expectancy, the NRR, and the mean age of fertility.
Stability takes several generations to arise, even more when one begins with a single cohort, and is slower for higher mean ages of fertility.
Table 1 shows the results for the time to decline (t*) projections for NRRs of 0.50 to 1, separately for mean ages of fertility of 25, 29, and 33 years and for life expectancies of 75 and 85 years.
And during obstetrics, when the effects of age on fertility were drilled into us, I was relieved I wasn't putting off pregnancy until I had completed residency in my mid-to-late 30s.
$ a m, a f genetic effects, pe m, pe f permanent environment effects for male and female fertility respectively #Degree: 0 = constant, 1 = linear regression, 2 = quadratic regression, 3 = cubic regression In the analyses presented, a cubic polynomial (m = 3) was used to model the fixed effect of age on fertility, as this described the observed mean weekly fertility profile.
This study focuses on consistency checks using average parity, age and sex distributions and age pattern of fertility as basis for evaluating fertility data derived from the four censuses.
