Population growth rates in perfect contraceptive populations

Abstract Eventually, world population must cease to grow. In many countries attempts are made to decrease population growth by providing family planning services to all who want to prevent pregnancies. In this paper we use the concept 'perfect contraceptive population',(1) - a population in which no unwanted births occur - to derive estimates of the maximum contribution that prevention of unwanted births might make toward attaining a zero rate of natural increase in population.     

Midpregnancy Marriage and Divorce: Why the Death of Shotgun Marriage Has Been Greatly Exaggerated

Conventional wisdom holds that births following the colloquially termed “shotgun marriage”—that is, births to parents who married between conception and the birth—are nearing obsolescence. To investigate trends in shotgun marriage, we matched North Carolina administrative data on nearly 800,000 first births among white and black mothers to marriage and divorce records. We found that among married births, midpregnancy-married births (our preferred term for shotgun-married births) have been relatively stable at about 10 % over the past quarter-century while increasing substantially for vulnerable population subgroups. In 2012, among black and white less-educated and younger women, midpregnancy-married births accounted for approximately 20 % to 25 % of married first births. The increasing representation of midpregnancy-married births among married births raises concerns about well-being among at-risk families because midpregnancy marriages may be quite fragile. Our analysis revealed, however, that midpregnancy marriages were more likely to dissolve only among more advantaged groups. Of those groups considered to be most at risk of divorce—namely, black women with lower levels of education and who were younger—midpregnancy marriages had the same or lower likelihood of divorce as preconception marriages. Our results suggest an overlooked resiliency in a type of marriage that has only increased in salience.     

Pregnancy status and unwanted births

Pregnancy status was examined in this study of 590 rural and 377 urban married women 15-45 years old from the northern Mindanao region of the Philippines. Pregnancy status was measured in terms of a Likertlike format of 32 statements pertaining to opinions on physical appearance, health concerns during pregnancy, attitudes of husbands and family members, and social activities during pregnancy. 16 items were identified by factor analysis as appropriate indicators. Status is related to the social benefits derived from the pregnancy period as a benefit with costs. Perception of pregnancy is related to unwanted births. Principal component analysis lead to the characteristics of SELF, which reflects feelings about self and how others relate to her pregnancy; WANT, which indicates the desires that influenced her pregnancy; and OTHERS, which reflects her feelings about how others treat her. Pregnancy Status Index Scores (PSINDEX) was a computation of the sum of scores for each variable divided by the number of items answered. The Eigenvalue for the 3 components accounted for 51.3% of the variance. The results showed that rural women had higher evaluations for all 3 components of PSINDEX, which means that pregnancy is seen as a beneficial means to improve marital and social relations as well as personal importance. SELF was the moist important category for both urban, (4.54) and rural women (4.65). Urban residents who considered SELF more important tended to be younger, less well educated, less modern, and less socially well off. In the bivariate analysis, findings indicated that rural women who were lower socioeconomically and had less education had a higher regard for pregnancy and a more positive attitude. Stepwise regression analysis revealed that PSINDEX, number of live births, number of years married, and a woman's educational attainment had significant effects on unwanted births. The maximum likelihood estimates indicated a good fitting model with an index of .997 and Chi square with 10 degrees of freedom of 6.80 (P.44). Among rural residents, the number of live births (path of .505) and pregnancy status (path of .109) had a direct effect on unwanted births. The higher the score on PSINDEX the lower the probability of having 1 or more unwanted births. In urban areas, education had a direct effect on unwanted births. Women who had been married longer, had less education, and fewer children were associated with pregnancy as an important factor in unwanted births. The rural model explained only 29% of the variance, while for the urban model 61%. Further exploration is recommended.     

The difference in unwanted births between blacks and whites

Blacks are more likely than whites to have unwanted births. A common explanation for that difference is that blacks use less effective contraceptive methods, use contraception less effectively, and use contraception less often than whites. Analysis of data from 17 cities in our family planning evaluation project suggested that, among women living in low-income neighborhoods, the black-white difference in unwanted births was not due to (1) blacks reaching desired completed parity at younger ages than whites, (2) differences in age or parity in our black and white samples, (3) black-white differences in current use of physician-administered contraception, or (4) blacks being more likely than whites to adopt physician-administered contraception after having an unwanted birth. Black-white differences which might have contributed to relatively more unwanted births among blacks were (1) blacks desired fewer children, (2) blacks were less likely than whites to use nonphysician-administered methods and more likely than whites to use no contraception, and (3) blacks had higher failure rates than whites subsequent to the adoption of physician-administered methods and when not using those methods. Comparisons are made with the 1965 and 1970 National Fertility Studies, and program implications of the findings discussed.     

The poor as a “perfect contraceptive population” and zero population growth

A goal of the federal family planning program is to enable women to have only those children they want, with priority given to the poor. Is that compatible with the goal of those who want zero population growth? This analysis shows that prevention of all unwanted births to women in low-income families would have yielded completed fertility much above that required for zero population growth.     

New strategies for slowing population growth

Growth of world population over the next 100 years, until the year 2100, will produce an estimated 11.5 billion people. The past focus on reducing rapid population growth exclusively through family planning has not been sufficient. Population policy needs to be broadened to include health care, education, and poverty reduction. The population policy recommendations of Population Council Vice-President John Bongaarts and Senior Associate Judith Bruce were to reduce unwanted pregnancies by expanding services that promote reproductive choice and better health, to reduce the demand for large families by creating favorable conditions for small families, and to invest in adolescents. The Population Council 1994 publication "Population Growth and Our Caring Capacity" outlined these issues. Another similar article by John Bongaarts appeared in the journal "Science" in 1994. In developing countries, excluding China, about 25% of all births are unwanted; 25 million abortions are performed for unwanted pregnancies. The provision of comprehensive family planning programs will go a long way toward achieving a reduction in unwanted pregnancies. In addition, changes are needed in male control over female sexuality and fertility and in cultural beliefs that are obstacles to use of contraception. Stabilization of population at 2 children per family will not occur unless there is a desire for small families. In most less developed countries, large family sizes are preferred. Governments have an opportunity to adopt policies that reduce economic and social risks of having small families. This can be accomplished through the widespread education of children, a reduction in infant and child mortality, improvement in the economic and social and legal status of women, and provision of equitable gender relations in marriage and child rearing. The rights of children to be wanted, planned, and adequately cared for need to be supported. These aforementioned measures will help to reduce fertility, provide support for small families, and justify investment in social development. Population momentum will keep population growing for some time even with replacement level fertility. Investment in adolescents through enhancement of self-esteem and promotion of later childbearing can lengthen the span between generations and slow population momentum. Population policies will be more effective when human rights are protected.     

Fertility intentions and maternal health behaviour during and after pregnancy

This study examines associations between fertility intentions and maternal health behaviours during and after pregnancy among a nationally representative sample of 3,442 women from India. Two waves of data (2005, 2012) from the India Human Development Survey were analyzed to investigate the influence of unwanted births on women’s use of antenatal care, timely postnatal care, and the delivery setting using binary and ordered logistic regression, partial proportional odds models, and propensity score weighting. Fifty-eight per cent of sample births were unwanted. Regression results show that, net of maternal and household characteristics, women with unwanted births were less likely to obtain any antenatal care and had fewer antenatal tests performed. Unwantedness was also associated with a lower likelihood of delivering in an institutional setting and of obtaining timely postnatal care. The relationships between unwantedness and antenatal care, postnatal care, and delivery setting were robust to models accounting for propensity weighting.     

Fertility Decline in Prussia: Estimating Influences on Supply,Demand, and Degree of Control

Change in marital fertility in 407 Prussian Kreise from 1875 to 1910 is modeled to depend on the gap between the number of desired surviving births, N*, divided by child survival, s, and the number that would be born under natural marital fertility, M, given the age at marriage. Some fraction of this gap is averted, depending on the propensity to avert unwanted births, D. Although none of these components is observed directly, we can estimate each indirectly under strong assumptions. Decline in N*/s accounts for twice as much of the decline in fertility as does an increase in D. Natural fertility rose during the period. Unwanted births increased slightly, despite a tripling of births averted. The most important causes of decline in N* were increases in female labor supply, real income, and health workers. A rising level of education is the most important cause of increasing propensity to avert births. Demand-side changes were important causes of the transition, but changes in readiness to contracept also were important, as was the interaction of the two.     

Family planning and reproductive health: the link to environmental preservation

This paper seeks to refocus the attention of environmentalists on the importance of population trends to environmental sustainability and identifies prevention of unintended pregnancy as potential common ground for environmentalists and family planning advocates. The health and other welfare benefits of preventing unintended pregnancy are felt most keenly by individual women, men, and their families. At the same time, however, preventing unwanted pregnancies usually results in smaller family size, an important factor in slowing population growth and, as a result, a source of broader benefits—including environmental benefits—to society.     

Children’s Experiences After the Unintended Birth of a Sibling

This study examines whether children with a younger sibling whose birth was unintended experience larger declines in the quality of their home environment and larger increases in behavioral problems than children whose younger sibling’s birth was intended. We use data from the NLSY79 to estimate cross-lag regression models that assess changes in the home environment and children’s behavioral problems after the birth of a sibling (intended or unintended). Results are consistent with our hypotheses, finding that, indeed, unintended births have negative spillover effects. Compared with children whose sibling’s birth was intended, both boys and girls whose sibling’s birth was unintended experienced larger declines in the quality of their home environment, and boys had larger increases in behavioral problems. We also find some unexpected evidence that mistimed births may have larger negative effects than unwanted births. This deserves further research, and we offer some possible explanations that could guide those investigations.     

The impact of induced abortion on black and white birth outcomes in the United States

This paper examines the impact of induced abortion on birth outcomes by treating abortion as an endogenous input into the production of infant health. To gauge the direct and indirect effects of abortion, three measures of infant health are considered simultaneously: the neonatal mortality rate, the percentage of low-weight births, and the percentage of preterm births. All three are race specific and all pertain to large counties in the United States in 1977. The results suggest that by preventing unwanted births, abortion enhances the survivability of newborns of a given birth weight and improves the distribution of births among high-risk groups.     

The Astonishing Population Averted by China’s Birth Restrictions: Estimates,Nightmares, and Reprogrammed Ambitions

China launched an unprecedented program to control its population in 1971. Experts have dismissed the official estimate of 400 million births averted by this program as greatly exaggerated yet neglect to provide their own estimates. Counterfactual projections based on fertility declines in other countries suggest that China’s program-averted population numbered 360–520 million as of 2015. The low end of this range is based on Vietnam—China’s best national comparator, with a two-child program of its own—and the high end is based on a 16-country comparator selected, ironically, by critics of the official estimate. The latter comparator further implies that China’s one-child program itself averted a population of 400 million by 2015, three-quarters of the total averted population. All such estimates are projected to double by 2060, due mostly to counterfactual population momentum. These and other findings presented herein affirm the astonishing impact of China’s draconian policy choices and challenge the current consensus that rapid socioeconomic progress drove China’s fertility well below two children per family. International comparisons of fertility and income suggest instead that China’s very low fertility arrived two or three decades too soon. If China had not harshly enforced a norm of 1.5-children during the last quarter century, most mothers would have had two children, one-half birth higher than observed.     

Adolescent alienation: Evaluating the hypotheses

Statistics reveal the steady, long-term, increase of self-and-other-destructive conduct among American youths. The conduct involved includes suicide, homicide, out-of-wedlock births, drug abuse and recorded crimes. A variety of hypotheses have been proposed to interpret this conduct — and to indicate possible remedies. Some of these hypotheses are briefly characterized, generally evaluated, and rejected. One hypothesis, the so-called youth bulge theory, suggests that the conduct is due to a disproportinate relationship between the youth population and the adult population; this disproportion — the so-called youth bulge — ultimately led to various modes of youth alienation. The youth bulge hypothesis was tested through a regression analysis which estimated the contemporaneous relationship between a measure of adolescent disorder (the youth suicide rate over time) and the proportion of youths to adults. A statistically significant but small relationship was found between the two variables. The implications of this conclusion are briefly sketched.     

Unwanted pregnancies and preventive health care use in Thailand

Research on the consequences of unwanted pregnancies can offer useful perspectives on the need to improve and expand the range of family planning options available to women in developing countries. This paper investigates the use of maternal and child health services by women who have unwanted or mistimed pregnancies. The results of our analysis indicate that wantedness of births exerts a significant influence on health care use in Thailand, after controlling for other determinants of utilization. Women with unwanted pregnancies are less likely to seek prenatal care or receive tetanus toxide inoculations. Further, women from disadvantaged socioeconomic groups, women with high parity and those with lower educational levels have the highest proportion of unintended pregnancies. The study concludes by making suitable policy recommendations.     

Post-disaster fertility: Hurricane Katrina and the changing racial composition of New Orleans

Large-scale climate events can have enduring effects on population size and composition. Natural disasters affect population fertility through multiple mechanisms, including displacement, demand for children, and reproductive care access. Fertility effects, in turn, influence the size and composition of new birth cohorts, extending the reach of climate events across generations. We study these processes in New Orleans during the decade spanning Hurricane Katrina. We combine census data, ACS data, and vital statistics data to describe fertility in New Orleans and seven comparison cities. Following Katrina, displacement contributed to a 30% decline in birth cohort size. Black fertility fell, and remained 4% below expected values through 2010. By contrast, white fertility increased by 5%. The largest share of births now occurs to white women. These fertility differences—beyond migration-driven population change—generate additional pressure on the renewal of New Orleans as a city in which the black population is substantially smaller in the disaster’s wake.     

China's New Demographic Reality: Learning from the 2010 Census

China conducted its sixth modern census in 2010, recording a total of 1.34 billion people. This article presents an overview of the early census results. The data are of reasonable quality but contain some apparent defects where adjustments may be required. The census confirms that China has entered the era of demographic modernity and depicts the vast transformation of the country's rural‐urban distribution. Life expectancy has risen by 3–4 years in the decade since the last census, while fertility remains well below replacement—probably as low as 1.5 births per woman—and the sex ratio at birth is still significantly elevated. Low fertility and falling old‐age mortality are leading to continued and rapid population aging. Several coastal provinces grew by as much as 40 percent in the last decade, while a number of inland provinces have recorded population decline. China has reached an overall urban proportion of 50 percent.     

The World Fertility Survey: charting global childbearing

Interviewing some 350,000 women in 42 developing countries and 20 developed countries representing nearly 40% of the world's population, the World Fertility Survey (WFS) is in a unique position to document the historic 1970s slowdown in global population growth. This Bulletin describes efforts begun in 1972 to ensure high quality, internationally comparable, accessible data, the data's importance for policymakers, planners and researchers, and major findings available by early 1982 from directly assisted WFS surveys in 29 developing countries and contraceptive use data from WFS-type surveys in 16 developed countries. Marital fertility has declined in all developing regions except Africa but still averages from 4.6 children/woman in Latin America to 6.7 in Africa, while preferred family size ranges from 3.0 children in Turkey to 8.9 in Senegal--far above the average 2.2-2.5 children/woman needed to end developing countries' population growth in the long run. However, women ages 15-19 prefer nearly 2 children fewer than the oldest women ages 45-49; 3.8 vs. 5.7 on the average. Nearly 1/2 (48%) of married women surveyed in 27 countreis said they wanted no more children. Preventing all unwanted births would reduce birth rates up to 15 births/1000 population in these countries. Overall, 32% of married, fecund women in developing countries are using contraception compared to an average 72% in 16 developed countries. Education, literacy, and more available family planning services increase contraceptive use. Age at marriage is rising in Asia, but this factor alone has little effect on fertility. Infant mortality is higher in many developing countries than previously thought. Breastfeeding is an important restraint on fertility in most developing countries but is declining among more educated, employed, and urban women which could raise fertility if not compensated for by gains in contraceptive use.     

Effect on unwanted fertility of extending physician-administered birth control in the United States

A goal of publicly subsidized family planning programs in the United States is to prevent unwanted births, and the primary means being used to achieve this goal is to increase coverage with physician-administered contraception, with priority being given to persons from low-income families. We analyzed data from families living in low-income neighborhoods to determine whether that means would contribute to that goal, and if so, how much unwanted fertility might be decreased through increased coverage with physician-administered methods.The results indicate that increased coverage with those methods would decrease unwanted fertility by 80 percent (79 percent among blacks, 83 percent among whites). Increasing the ratio of sterilization to pill and IUD makes the effect of the increased coverage even more dramatic.     

The effectiveness of medical interventions aimed at preventing preterm birth: a literature review

Background

Preterm birth is a significant global health problem with serious short and long term consequences. This paper reviews the research literature to answer the question how effective are the medical interventions that aim to reduce the rates of preterm birth?

Methods

A systematic search was carried out in CINAHL, Cochrane, Medline and Embase in relation to following medical treatments aimed at preventing preterm births: anti-infective medications, tocolytics, progesterone and cervical cerclage. The research underpinning each type of intervention is critically analysed in order to establish the validity of knowledge claims that are made for each type of intervention.

Findings

In relation to reducing the rates of preterm births, anti-infectives are only effective in the presence of known infection. Screening for infections during pregnancy is ineffective. Tocolytic agents are not effective in decreasing the preterm birth rates. Progesterone seems to be effective in a select group of pregnant women at higher risk of preterm birth. Cervical cerclage plays a small and an occasional role in preventing some preterm births.

Conclusions

This literature review demonstrates that medical interventions aimed at preventing, not just delaying, preterm birth, are not effective at a population level. Providing holistic, antenatal midwifery care for women living in socio-economic disadvantage and/or with an increased risk of preterm birth seems to be a promising strategy to address the negative effects of the social determinants of disease and thus to reduce the rate of preterm births at an individual and a population level.