Overview of Todays Topics

1
Overview of Todays Topics

• Example of Utah Population Database
• Calculating Marriage Rates
• Fertility
• Yikes Midterm

2
Fertility and LongevityAre Kids Good For You?
3
Priscilla and Lee Arrington, 1906 Both age
48 Priscilla bore 9 children (8 shown), the last
at age 43
4
Lee and Priscilla Arrington, 1948 or 1949, 90
years old
5
Jeanne Louise Calment Died 1997 at age
122 Longest-lived person with authenticated
records Bore one child
6
The oldest man in the United States last year
from heart failure at the age of 113. John
McMorran, who was born June 19, 1889, in a log
cabin in Michigan, considered coffee his elixir
and quit cigars at age 97. He was the
fourth-oldest person in the world.
7
Why Should Children Affect Your Life Span After
50?
8
Parental Health and Longevity Benefits of
Children to Men and Women
Children as sources of social support Children in
times of need (widowhood, illness) Children
enhance social integration Providing a sense of
purpose Children reduce parental
risk-taking Reduced risk of some cancers (breast,
ovarian) With late fertility, enrich life in
middle and older ages
9
Parental Health and Longevity Costs of Children
to Men and Women

• Greater fertility (children and grandchildren)
  may limit accumulation of wealth
• Intergenerational resource flows may be more
  downward than upward
• Maternal mortality
• Late fertility - being an old parent with young
  children prospect of being widowed with young
  children

10
Parental Health and Longevity Children
Represent Other Factors

• Lower Socioeconomic status couples tend to have
  both higher fertility and reduced longevity
• Association between historical epochs and
  mortality and fertility schedules
• Religion, longevity, and fertility - members of
  the LDS Church

11
Theory of Disposable Soma

• Because of competing demands of reproduction,
  less effort is invested in the maintenance of
  somatic tissue than is necessary for indefinite
  survival.

From Nature 1998 396719
12
Late Natural Reproduction in Females

• Slow aging ovaries may mean slow overall rates of
  aging
• Late Natural Menopause vs. Late Fertility
• Positive association between female longevity and
  late fertility
• Perls et al, 1997 - 76 centenarians, 54 controls
  in Boston
• Positive association between female longevity and
  late natural menopause
• Snowdon et al, 1989 - Seventh Day Adventists
• Cooper and Sandler, 1998 - NHANES I

13
Flies, Aristocracy, and Nuns
14
Utah Population Database (UPDB)
15
Survival Past Age 60 By Sex, Utah 2000
Female Life expectancy 25.5
Male Life expectancy 21.8
3.7 Year Difference in Life Span
AGE
16
Survival Past Age 60 By Sex,Among Married
Couples, Utah 1890
Female Life expectancy 21.2
Male Life expectancy 17.7
3.5 Year Difference in Life Span
60 70
80 90
100

AGE
17
Is More BetterEffects of Parity
18
3 Year Difference in Life Span Between Parity 1-3
and Parity 15
Females Parity 1-3
Females Parity 15
19
Effect of Parity on Exceptional Longevity
Significantly different longevity from average
fertility (7-11 children)
Odds Ratio
Died After 93 vs before 85
Died After 91 vs before 83
20
The Last OneAge at Last Birth
21
(No Transcript)
22
Effect of Wifes Age at Last Birth on
Exceptional Longevity
Odds Ratio
Died After 93 vs before 85
Died After 91 vs before 83
23
(No Transcript)
24
Marriage and Unions

• Nuptiality
• Multiple states
• Never-married
• Cohabiting
• First Marriage
• Divorce
• Separated
• Widowed
• Remarried (sometimes to previous spouse)
• Same Sex unions
• Death
• Polygamy (Polygyny, Polyandry)

25
Crude Marriage Rates
M-Type Crude Marriage Rate Number of marriages
in a given year Total mid-year population

• Denominator includes the young
• Affected by age structure
• Ignores marriage order
• Denominator includes those not at risk (already
  married)

26
General Marriage Rates
M-Type General Marriage Rate Number of
marriages in a given year Total mid-year
population 15 yrs or older

• -Affected by age structure
• Ignores marriage order
• Denominator includes those not at risk (already
  married)

27
(No Transcript)
28
Age at First Marriage By Year-Women
29
Age at First Marriage By Year- Men
30
Age-Specific Marriage Rates
M-Type Age-Specific Marriage Rate Number
marrying at Age x at last BD Mid-year population
Age x at last BD
31
Decremental vs Non-Decremental Rates

• Decremental Rates
• Includes only those at risk in the denominator
• Non-Decremental Rates
• Includes the entire population in the denominator
• Decremental is always preferred but can be
  tougher to calculate
• Q type rates, Kaplan-Meier, Cox Regression all
  use Decremental rates

32
Total First Marriage Rate
If x15 and y30 then the (partial) TFMR would
tell you the proportion of people who first
married between ages 15 and 30. This is a
non-decremental rate because the denominator
includes already married persons.
33
Q vs M Type Marriage Rates

• For non-decremental rates, they are the same
• .. If you assume that marriage and divorce rates
  do not vary by calendar year and that they occur
  evenly within the year.

34
Current Status Data

• Stable population and synthetic cohorts
• See Table 7.3 and Figure 7.3

35
Fertility
36
Fecundity

• Fecundity
• Potential to reproduce.
• A fecund person is usually in good health, with
  normal ovulation or sperm production, although
  s/he may not yet have conceived a child.
• Few women reproduce at the maximum potential rate
  of 15 to 20 children in a lifetime, but a man may
  have this many (or more) offspring.

37
Sub-Fecundity

• Reproduction below the usual rate. 
• The percentage of women who never become pregnant
  or carry a fetus to full term varies greatly by
  society, from 2 percent up to almost 50 percent. 
  
• Many environmental and biological factors
  contribute to sub-fecundity, including
  under-nutrition, disease, and stress.

38
Fertility

• Reflects actual reproduction.
• Measured in many ways
• completed fertility
• age-adjusted
• age-specific fertility
• Total fertility rate

39
Completed Fertility

• Number of children born during a womans
  reproductive lifetime
• Generally calculated at an age after women reach
  menopause (age 50).
• Average completed fertility today
• Hutterite farmers in Canada 9
• Brazil 2.9
• Japan 1.7
• Even without contraception or abortion,
• !Kung San, hunter-gatherers of Africa 4.1
• Yanomamo of Venezuela 3.8
• Reduced fertility in these societies included
  prolonged, intensive breastfeeding that inhibited
  ovulation, seasonal under-nutrition (also
  suppressing ovulation).

40
Where to Get Fertility Data?

• CDC/National Center for Health Statistics
• Vital Records
• Births
• Reporting is done at the state-level
• http//www.cdc.gov/nchs/ or http//esa.un.org/unpp
  /index.asp?panel2/ or
• www.prb.org
• Denominators
• US Census Bureau

41
Age at First Birth
42
(No Transcript)
43
(No Transcript)
44
(No Transcript)
45
Total Births, Utah, 1940-2000
46
Crude Birth Rate

• Simplest but most naïve
• The crude birth rate is often used simply because
  data are available.

47
Crude Birth Rate

• Why is it naïve?
• Many people in the population cant have
  children
• Ignores age structure of women who can have
  children.

48
(No Transcript)
49
General Fertility Rate (GFR)

• Advantage - only women of reproductive age
  included
• Disadvantage ignores age structure of women who
  can have babies with ages 15-49

50
Question about the GFR

• Should we use number of women aged 15-49 or
  15-44?
• Very little childbearing age 44-49
• However, childbearing in this age group is rare
  but is is increasing in developed societies.
  Fertility treatments, income women are less
  constrained by age.
• Age bracket 40-44 years has often shown the
  biggest increase wise in the last few years in
  the US but from a very low base.

51
Age-Specific Fertility Rates
52
(No Transcript)
53
Age-Specific Fertility Rates, Utah vs. US, 1980
An age specific fertility rate is the proportion
of women of a specific age who give birth during
a given year. nfx nBx / nFx nfx is the age
specific fertility rate of women aged x to
xn. nBx is the number of births to women aged x
to xn over the year. nFx is the number of women
aged x to xn at midyear.
54
Age-Specific Fertility Rates, Utah vs. US, 1990
An age specific fertility rate is the proportion
of women of a specific age who give birth during
a given year. nfx nBx / nFx nfx is the age
specific fertility rate of women aged x to
xn. nBx is the number of births to women aged x
to xn over the year. nFx is the number of women
aged x to xn at midyear.
55
Age-Specific Fertility Rates, Utah vs. US, 1999
An age specific fertility rate is the proportion
of women of a specific age who give birth during
a given year. nfx nBx / nFx nfx is the age
specific fertility rate of women aged x to
xn. nBx is the number of births to women aged x
to xn over the year. nFx is the number of women
aged x to xn at midyear.
56
Age-Specific Fertility Rates, Utah Regions, 1999
1 Box Elder, Cache, Rich 2 Davis, Morgan, Salt
Lake, Tooele, Weber, Summit 3 Wasatch, Utah 4
Juab, Millard, Piute, Sanpete, Sevier, Wayne 5
Beaver, Garfield, Iron, Kane, Washington 6
Daggett, Duchesne, Uintah 7 Carbon, Emery,
Grand, San Juan
57
Total Fertility Rates
58

• TFR measures the expected number of children a
  woman now at the beginning of her childbearing
  would have if she experienced current fertility
  levels for the whole of her reproductive life.
•  
• e.g. if a woman aged 15 has these current
  fertility rates for the whole of her reproductive
  life. Making huge assumptions that nothing
  changes for those now aged 15 for the next 35
  years. How do we do that?

59
(No Transcript)
60
Total Fertility Rate Utah and US, 1960-1999
Utah
US
61
Total Fertility Rate
In order to calculate this rate you need data for
a period of time (one year)
62
Birth-Order Total Fertility Rates
Fertility Rate of women in age-group x who give
birth to their jth child
Total Fertility Rate of women for the jth child
63
Parity Progression Ratios
PPR Proportion of women of a given parity who
go on to have another child
64
Cohorts
A
B
C
100
Age
True Parity Cohorts
75
Synthetic Parity Cohorts
50
25
0
1950
1975
1925
2000
2025
Calendar Year (Period)
65
Data Structure
Year when 2nd Child is Born
True Parity Cohorts
Year of Birth of 1st Child
Synthetic Parity Cohorts
66
Go to Excel File for Table 9.1