Propose a series of intermediate fertility variables that determine natural fertility and fertility regulation

three more general sub-categories of intermediate fertility control variables exposure to sex, exposure to contraception, abortion (unplanned and planned).

8 intermediate fertility variables

1) proportion married,

2) contraception,

3) induced abortion,

4) lactational infecundability,

5) frequency of intercourse,

6) sterility,

7) spontaneous intrauterine mortality, and

8) duration of the fertile period

“Some data on natural fertility.” Eugenics Quarterly, 8, 81-91.

Natural fertility is fertility that exists in the absence of deliberate birth control; i.e. fertility that is not based on the number of previous children a couple has

2 difficulties with determining natural fertility

- Difficulty findings populations without birth control

- Difficulty collecting reliable data from these populations

Argues that natural fertility varies between populations due to differences in the resumption of sexual relations or reappearance of ovulation following birth of a child

- One problem with Henry’s analysis was that he only analyzed differences in stopping behavior once women had achieved desired number of children

- He overlooked starting behavior, or when women choose to begin having children

- For some reason, he believed that the age at marriage did not matter for fertility

“A framework for analyzing the proximate determinants of fertility.” Population and Development Review, 4(1), 105-132.

Objective of paper is to develop a model for how intermediate variables affect the total fertility rate

- The intermediate fertility variables are those that have a direct bearing on fertility; they are determined by various socioeconomic, cultural, and environmental variables

- The value of the intermediate fertility variables is that they allow for the identification of paths through which different social variables affect fertility

8 intermediate fertility variables were proposed by Kingsley and Blake (1956); these were

1) proportion married,

2) contraception,

3) induced abortion,

4) lactational infecundability,

5) frequency of intercourse,

6) sterility,

7) spontaneous intrauterine mortality, and

8) duration of the fertile period

- Variations in fertility can alwaus be traced to variations in one or more of these intermediate variables

- However, each variable’s degree of influence depends on societal factors

- According to Bongaarts, 4 of these 8 variables can be controlled by individuals and are responsible for most of deviations from natural fertility:

1. the proportion married at each age,

2. prevalence of abortion,

3. prevalence and effectiveness of contraception, and

4. length of infecund period following a birth

- It is important to note that an induced abortion always averts less than one birth because it may have been unnecessary if the baby dies anyways and because a woman resumes ovulation much sooner if she has an abortion than if she carries her baby to term

Bongaarts calculates the total natural fertility rate (TF) to be approximately 15.3 births per women

- This is how many births a woman would have if every fecund women were married and exposed to the risk of pregnancy, no one used contraception, no one had an abortion, and no one breastfed or abstained from sex following a birth

- One question remains regarding the role of nutrition and health in determining fertility

Bongaarts argues that overall, nutrition has little direct influence on fertility

However, it can be indirectly linked to fertility by affecting infant mortality, adult mortality (and the risk of widowhood), and perhaps by affecting the length of the period of lactational infecundability

- In light of the above discussion, Bongaarts calculates the following model for the TFR as a function of these 4 intermediate variables

TFR = TF * Cm * Cc * Ca * Ci

TF=Natural Fertility (15.3)

- Cm, Cc, Ca, and Ci are indices of marriage, contraception, abortion, and infecundability

- Range from 0 (indicating total inhibition of fertility) to 1 (indicating no inhibition of fertility)

- Using this model, Bongaarts finds that the primary driver of American fertility decline from 1965-1973 was an increase in the use and effectiveness of contraception

The Effects of Infant and Child Mortality on Fertility. “Introduction.” New York, NY: Academic Press.

Aim of article is to evaluate how changes in child mortality may affect changes in fertility

- It has been theorized that a decline in child mortality is necessary for family planning to be effective because families need to bear fewer children to achieve a particular desired number of surviving children

Some mechanisms that link child mortality to fertility

Interval effect: the interval between births is elongated by breastfeeding; death of child -> less time spent breastfeeding -> smaller interval between births

Postpartum abstinence: Some cultures believe that if you get pregnant too soon after giving birth you will be stealing resources from newborn; this leads to taboo against sex after giving birth

- Particularly common in West Africa

Replacement strategy: Parents want to have x number of kids by the end of the reproductive period; if any die before end of period they try to replace them

Insurance strategy: Parents want to have x number of kids at some point in the future; they have more than x kids as a form of insurance against later deaths

Nevertheless, replacement is often incomplete because one child’s death often does not result in another child’s birth

Some reasons why replacement may be incomplete include . . .

- Couple has no target number of surviving children

- The target is so high it could not be achieved even if all children survived

- Targets are framed for one sex only

- Control of fertility is imperfect (couple may be unable to replace child even if they want to)

- Death produces a downward modification of target

- Child death was anticipated and additional children born as an insurance strategy

Some extrafamilial mechanisms that may also link mortality decline and fertility decline include decreased standard of living and/or increased migration associated with population growth

“The fertility-inhibiting effects of the intermediate fertility variables.” Studies in Family Planning, 13(6/7), 179-189.

Paper is to demonstrates that differences in fertility among populations are primarily due to variations in only four intermediate fertility variables

- Uses the following model to estimate the TFR from the 4 intermediate fertility variables, and compares these estimates to the actual TFRs from various countries

            TFR = TF *Cm *Cc *Ca *Ci

- Finds that these 4 variables explains 96% of the variance in the TFR from 41 populations

- The variance in the TFR that is not explained by these factors is due to errors in measurement of the intermediate variables, deviations in total fecundity from 15.3, errors in observed TFRs, absence of data on induced abortions, and inclusion of illegitimate births from developing countries

Then analyses the role of each of these 4 variables in the reduction of fertility over the course of the demographic transition

1. The main reason for the decline in fertility is the increase in contraceptive use and effectiveness

2. Marriage also plays a role as women begin to marry later

3. The mean duration of postpartum infecundability actually falls over the course of the transition because fewer women breastfeed in more developed societies

4. The prevalence of induced abortion plays almost no role

 “Chapter 2: Theoretical Framework.” In The Fertility Revolution. Pp. 12-31.

Authors propose 3 economic fertility determinants that mediate the relationship between economic and social conditions and proximate determinants of fertility that are under an individual’s control (contraception, abortion)

- All of the basic determinants of fertility work through one or more of the following economic determinants to influence proximate determinants

First, demand for children

- The number of surviving children that parents would want if fertility regulation was costless

- Determined by income, price, and tastes

Second, the supply of children

- Number of surviving children a couple would have if they made no attempt to limit fertility

- Determined by natural fertility and child mortality

Third, the costs of fertility regulation

- Couple’s attitude toward and access to fertility controls

- As long as demand for children is higher than supply of children, parents won’t be motivated to regulate fertility

- When demand for children is less than supply, and when contraception becomes widely accepted and available, fertility begins to fall

- For a while, supply of children will persist at a level higher than demand

- Not until the point of “perfect contraception” will demand for children = supply of children

- Different aspects of modernization (such as public health, education, urbanization, new consumer goods, new methods of birth control, and new family planning programs) affect fertility via these 3 variables

- More empirical research on exactly how and to what extent these aspects of modernization impact these 3 economic variables is necessary

- This line of research prompted trends in the 1990s to fill an unmet need for contraception in developing countries

“Parity progression and birth intervals in China: The influence of policy in hastening fertility decline.” Population and Development Review, 19(1), 61-101.

Analyzes parity progression and birth interval statistics in relation to the Chinese government’s birth planning policies

Data come from China’s 1988 two-per-thousand survey

Results

- Marriage remains essentially universal in China

- Age at marriage varies somewhat by region (rural, town, city) with individuals from more urban areas marrying later

- There was actually a decline in the age at first marriage in 1979 following the introduction of the one-child policy because this policy relaxed prior restrictions on early marriage present in the later-longer-fewer policy

- Vast majority of couples have at least one birth

- In the 1970s, prior to the one-child policy, 95% of women went on to have a second birth

- With the intro of this policy in 1979, period progression ratios fell greatly, reaching a low of 62 in 1984, and rebounding to 77 in 1987

- One child policy had largest effects in the cities

- In 1978, 87% of women had second birth; in 1983, 11% had second birth!

- Close to half of women in the 1980s who had a second birth went on to have a third

- Very different picture in cities, however, where only 10% of women with a second child have a third

- Although not many women have 4 or more births, the proportion is fairly high given the strict policies in place

- 35% progress to higher order births, although most of this occurs in rural areas where policy implementation is weak

In sum, age at marriage and fertility were almost certainly influenced by policy

- Nevertheless, shouldn’t forget that fertility may have declined even in the absence of government intervention, although it’s highly unlikely the declines would have been so dramatic

- In rural areas and towns especially, where the role of societal factors was to resist decline, policy played a big role

- The results also reveal limitations of China’s population policies, including difficulty achieving policy objectives in country as a whole due to higher rates of fertility in rural areas and towns compared to cities

 “On the modernity of traditional contraception: Time and the social context of fertility.” Population and Development Review, 28(2), 229-249.

Argues that social goals other than just avoiding fertility influence women’s choice of contraceptive method

- Focuses on the Beti population in South Cameroon

- Periodic abstinence is the most common method of fertility control practiced in this population—primarily among young, educated, progressive women

- 2 naïve theories about why Beti women choose this method are that these women are not strongly committed to contraception or that they are uninformed about the availability and low cost of modern contraception

- Johnson-Hanks shows that neither of these arguments hold true

- Though this might not be the most effective method, these women are strongly motivated to avoid a birth

2 main reasons why periodic abstinence is the preferred method

1. Fear of harmful side effects of modern methods

2. Successful periodic abstinence seen as honorable

- Women who engage in periodic abstinence are seen as self-disciplined, moral, and powerful (for instance, this method gives women strong negotiating power in their sexual relationships)

- Progressive family planning in Beti society focuses more on well-timed births than on total family size