Effects of polygyny and consanguinity on high fertility in the rural Arab population in South Jordan

Based on the authors' interview survey for 608 randomly selected women of the rural Arab population in the South Ghor district of Jordan, this paper examined the effects of polygyny and consanguinity on high fertility, which was recognized as natural fertility. The prevalence of polygynous and consanguineous marriages was 28.0% and 58.1%, respectively, largely reflecting the population's traditional marriage customs. The findings highlighted a significantly higher total marital fertility rate (TMFR) in the monogamous wives (10.5) than in the senior polygynous (8.1) and junior polygynous wives (8.6); the TMFR did not significantly differ among the wives of non-consanguineous, first-cousin and second-cousin marriages. The formation of polygynous marriage was decided by the husband, mostly as a result of his senior wife's infecundity or sub-fecundity, and the age of the husband at marriage to his junior polygynous wife was high in many cases, leading to a decline in this wife's fecundity.     

Are wives and daughters disadvantaged in polygynous households? A case study of the Arsi Oromo of Ethiopia

Whether polygyny is harmful for women and their children is a long-standing question in anthropology. Few studies, however, have explored whether the effect of polygyny varies for women of different wife order, and whether there are different outcomes for their sons and daughters. Because males have higher reproductive variance, especially when they are allowed to take multiple wives, parents may have higher fitness returns from investing in sons over daughters in polygynous households. Moreover, previous studies have found that first wives and their children are advantaged over monogamous and second order wives (who marry into unions later). Here we test the predictions that children of first wives will have an advantage over children to monogamous or second wives, and that sex-biased investment will be strongest among first wives. Using data from the Arsi Oromo of Ethiopia (n ~ 6200 children) we test whether associations with mother's wife order extend beyond childhood into adulthood by examining simultaneously child survival, education and age at marriage. We find that polygynous first wives have no child survival disadvantage, first wives' sons benefit in terms of longer education and daughters have an earlier age at marriage than daughters of monogamous women. Second wives have lower child survival than monogamous women, but surviving children experience advantages in later life outcomes, particularly marriage. These findings challenge the view that polygynous women are always doing the ‘best of a bad job’. Rather, our results suggest that via their surviving sons and daughters there may be long-term benefits for some polygynous women.     

Differentials of fertility between polygynous and monogamous marriages in rural Bangladesh

This paper discusses polygynous marriages in rural Bangladesh, using marital status and birth registration data from the Demographic Surveillance System (DSS) of the International Center for Diarrheal Disease Research, for the period 1975-79. Of all the marriages recorded during this period about 5% were polygynous. To identify the women polygynously married, 1974 census data of the DSS area were used. The difference in age at marriage between the polygynous groom and his subsequent wife was 15 years on average. The socioeconomic indicators studied were education, occupation and area of dwelling space. In general, these indicators between women in monogamous marriages were significantly higher than between the women in polygynous unions. During the period 1976-79, 863 polygynous marriages were recorded (4.9% of all marriages in the study area). Polygynous marriages were found to be less frequent among men with 2ndary and higher levels of education. The highest proportion of polygynous marriages occurred among husbands with no schooling or Koranic education. The general fertility rate of women in monogamous marriages was significantly higher than for women in polygynous marriages, overall and in all age groups except 20-24. During the period 1975-79, the mean number of liveborn children for monogamous women was higher than that of polygynous women.     

Marital fertility in polygynous unions in Nigeria

The effect of polygyny on fertility, by age cohort, was examined in 4 regions of Nigeria through use of data from the 1981-82 Nigerian Fertility Survey. Simple tabulation of numbers of live births by maternal age and type of marriage union indicated that, with the exception of the 30-39-year age group, fertility in polygynous unions tends to be higher than that in monogamous marriages. Overall, such tabulations reveal an average of 3.90 births among polygynous women and 3.47 births among monogamous women. However, when age-specific fertility rates were compared, except for women under 20 and over 40 years of age, rates were higher in monogamous unions (7.286 overall) than for women in polygynous households (7.200 overall). Mean completed fertility, taking into account marriage duration as well, shows a tendency for women in polygynous unions to be more fertile (with the exception of women aged 25-44 years who had been married 10-19 years). The absolute difference in fertility between the 2 types of marital unions ranged from 0.32 children in the northwest to 0.64 in the southeast. With adjustment for independent variables such as education, the absolute mean differences were reduced, from between 0.28 children in the southeast to 0.42 in the northeast, but the direction of high fertility was still in favor of women in polygynous unions. But when the covariates (e.g., age at marriage) were taken into account as well as the independent variables, there was a dramatic reduction in the mean difference between the fertility of these 2 groups of women. These findings suggest that some changes in reproductive behavior are taking place in Nigeria that are restricting the fertility of women in polygynous unions. These changes are hypothesized to reflect the spread of formal education in Nigeria, with the expectation that women will contribute to the costs involved in educating their children.     

Marriage structure and contraception in Niger

Analysis of the 1992 Niger Demographic and Health Survey showed that although roughly two-thirds of both polygamous and monogamous women approve of birth control, polygamous wives are less likely than monogamous wives to discuss family size or birth control with their husband or to plan on using birth control. The study suggests that characteristics of polygamous couples have caused polygamous women to be more resistant to birth control use than monogamous women. The polygamous women tended to be married to older men who had not gone to primary school and who desired more children than monogamous husbands. The influence of marital structure is not significantly associated with intention to use birth control when the husband's age and the wife's ideal number of children were controlled for in the multivariate logistic regression model suggesting that background social factors may be more influential. In fact, educational level and age at first marriage were significantly associated with attitudes towards birth control and also with marital structure.     

Preference for children and subsequent fertility in Matlab: does wife-husband agreement matter?

This study examines wife-husband preference for children and subsequent fertility for a period of 5 years in the treatment and comparison areas of Matlab, Bangladesh. The two data sets used were: the In-depth Survey (1984) and the Demographic Surveillance System (1984-89). In the case of wives' preferences for children, subsequent childbearing was 13.8% higher than desired in the treatment area and 44.7% higher than desired in the comparison area. After controlling for all variables in the model, the likelihood of giving birth was 1.78 times higher for wives who wanted no more children, but whose husbands did want more, compared with couples where neither husband nor wife wanted more children. For couples where the wife wanted more, but the husband did not want more children, the likelihood of giving birth was 0.63 times that of couples where both the husband and wife wanted more children. This finding suggests that to enhance the decline in fertility in these two areas of Matlab, it will be necessary to motivate both wives and husbands to cease childbearing.     

Polygamy and fertility in Somalia

The 1983 Somali Family Health Survey showed that polygamy and monogamy selected women with different social characteristics. Wives in polygamous unions were prone to be younger at first martial cohabitation and to have previous marital disruptions. Since a young age at first cohabitation and number of previous marriages have opposite effects on the cumulative fertility rate of women, the difference in this rate between wives in polygamous and monogamous unions vanished when both factors were controlled in a multivariate analysis.     

Harijans and Girijans of Andhra Pradesh: an application of analysis of variance in the study of fertility,mortality and family planning

Research on the Bagatha tribe and the Malas and Madigas in India has been done for economic and social planning purposes in regard to family planning. Bagatha are mostly agricultural people where the nuclear family is prevalent and polygamy is popular as well as cousin marriage. The Madigas and Males (Harijans) are lower caste with the 1st being leather workers and the latter being agricultural helpers. The data was collected by direct interview of 202 tribesmen and 202 caste households with women from 15-49 years of age. The data collected on fertility include live births, child survival rate, fetal wastage, husband and wives education, income, and occupations. On mortality, the number of deaths, age at marriage, number of and intervals of pregnancies. As expected, educated and employed families show healthier and higher levels of fertility especially if the wife is educated. The wife shows more of the responsibility for family planning. The age at marriage and the number of pregnancies appears to have little effect on mortality. In the caste group the education level of the husband has little effect on fertility and again the wife has the primary responsibility in using family planning techniques.     

Polygyny, reproductive success and child health in rural Ethiopia: why marry a married man?

This study examines the reproductive success of men and women in rural Ethiopia as a function of their marital status, specifically by comparing polygamously and monogamously married individuals. In line with predictions from evolutionary theory, polygamy is beneficial to male reproductive success (i.e. producing larger numbers of surviving offspring). The success of polygamously married females depends on wife rank: the first wives of polygamous husbands do better than monogamously married women and much better than second or third wives. These effects are mirrored in child nutritional status: the children of second and third wives have lower weight for height. Due to potential, largely unmeasurable differences in marriageability (quality) between individuals, it was not possible to support a model of either resource-holding polygyny combined with female choice or female coercion into unwanted marriages. First wives of polygamously married men marry at a younger age and attract a higher brideprice, suggesting that both the males and females in the marriage are likely to be of higher quality (due to wealth, family status or some other factor such as beauty). Unions that end up monogamous are likely to be between slightly lower quality individuals; and second and third wives, who marry at the oldest ages and attract the lowest brideprice, may be 'making the best of a bad job'. The relatively long gap between first and second marriages may mean that first wives of highly marriageable males can enjoy considerable reproductive success before their husbands marry again.     

Steroid hormones and immune function: experimental studies in wild and captive dark-eyed juncos (Junco hyemalis)

Monogamous and polygynous male songbirds generally differ in their breeding season profiles of circulating testosterone. Testosterone level spikes early in the breeding season of monogamists and then declines, but it remains high in polygynists. Male dark-eyed juncos (Junco hyemalis) are socially monogamous and exhibit the usual pattern, but experimental maintenance of high testosterone throughout the breeding season alters normal behavior and physiology and affects various components of annual reproductive success but not overall annual success. Because stabilizing selection predicts that alteration of naturally existing phenotypes should reduce lifetime reproductive success, we asked whether prolonged testosterone exposure might impair immune function and perhaps thereby reduce life span. We assessed immune function in captive and wild male juncos that we treated with either testosterone-filled or empty Silastic implants. Results indicate that prolonged elevation of testosterone suppresses antibody production in captive males and cell-mediated immunity in wild males. Together these results suggest that testosterone-treated males may be more susceptible to disease or parasitic infection. As earlier studies have shown, levels of corticosterone as well as testosterone are higher in testosterone-treated males, so it is unclear whether the immune suppression we observed is due to testosterone's direct effects on immunity or testosterone's influence on glucocorticoid production. We discuss results in the context of recent hypotheses regarding life-history theory and potential endocrine-immune interactions.     

The puzzle of monogamous marriage

The anthropological record indicates that approximately 85 per cent of human societies have permitted men to have more than one wife (polygynous marriage), and both empirical and evolutionary considerations suggest that large absolute differences in wealth should favour more polygynous marriages. Yet, monogamous marriage has spread across Europe, and more recently across the globe, even as absolute wealth differences have expanded. Here, we develop and explore the hypothesis that the norms and institutions that compose the modern package of monogamous marriage have been favoured by cultural evolution because of their group-beneficial effects-promoting success in inter-group competition. In suppressing intrasexual competition and reducing the size of the pool of unmarried men, normative monogamy reduces crime rates, including rape, murder, assault, robbery and fraud, as well as decreasing personal abuses. By assuaging the competition for younger brides, normative monogamy decreases (i) the spousal age gap, (ii) fertility, and (iii) gender inequality. By shifting male efforts from seeking wives to paternal investment, normative monogamy increases savings, child investment and economic productivity. By increasing the relatedness within households, normative monogamy reduces intra-household conflict, leading to lower rates of child neglect, abuse, accidental death and homicide. These predictions are tested using converging lines of evidence from across the human sciences.     

The auxiliary treatment of psychotic women; group therapy for their husbands

Group therapy for the husbands of hospitalized psychotic women relieved the anxiety and feeling of guilt of the husbands and led to better communication between husband and wife. It was particularly helpful just before and after the wife came home from the hospital. The group meetings saved various members of the hospital staff considerable time which they otherwise would have had to devote to the husbands individually.     

THE AUXILIARY TREATMENT OF PSYCHOTIC WOMEN—Group Therapy for Their Husbands

Group therapy for the husbands of hospitalized psychotic women relieved the anxiety and feeling of guilt of the husbands and led to better communication between husband and wife. It was particularly helpful just before and after the wife came home from the hospital. The group meetings saved various members of the hospital staff considerable time which they otherwise would have had to devote to the husbands individually.     

The effect of husbands' fertility preferences on couples' reproductive behaviour in rural Bangladesh

Bangladesh society is profoundly gender stratified, and yet male roles in reproductive health processes have not been rigorously investigated. This study examines the association between men's reproductive health knowledge, attitude and behaviour and their wives' subsequent reproductive behaviour using longitudinal data from the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B). A total of 4969 matched husband-and-wife data from a 1998 survey and women's contraceptive use history data following this survey are used. Results show a significant association between husbands' fertility preferences and current use of any family planning method. When wives' background characteristics, and husbands' background and socioeconomic characteristics are controlled for, the predicted probability of using a method of contraception among non-educated wives whose husbands want more children is 0.49 compared with 0.64 for those whose husbands do not want more children. However, the net effect of husbands' preference for additional children diminishes as wives' level of education increases. Among wives who had completed high school, the predicted probability of using a method of contraception is 0.70 for those whose husbands want more children compared with 0.69 for those whose husbands do not want more children.     

Male fertility attitudes: a neglected dimension in Nigerian fertility research

A sample of 202 male Nigerians enrolled in colleges and graduate schools in the state of Kansas were surveyed to determine their perceptions of population problems in Nigeria; attitudes toward family planning, divorce, and male children; and attitudes toward family size. A major limitation of Nigerian-based fertility research has been the neglect of the role of men in couples' reproductive behavior. The majority of Nigerian students surveyed in this study did not think overpopulation is an impending crisis in Nigeria: 40% thought there are just enough people and 13% indicated there are not enough people. 53% supported the concept of a government population policy, but 67% felt the government should not interfere with family size decisions. Although 84% endorsed the idea that family planning services and information should be available, 69% felt women should not practice family planning without the consent of their husbands. 43% believed a man should divorce his wife if the woman is infertile, unable to produce a male child, or unable to bear the number of children demanded by her husband; in addition, 35% indicated a man should marry a second wife or continue to have children if the couple has 5 daughters and no son. In terms of the value of children, 62% stated that children are wealth or better than wealth, whereas 38% claimed that children use up wealth. Duration of stay in the US was inversely correlated with the number of children considered too many, and the number of male children already born was an important determinant of future family size expectations. In general, it appears that level of education and exposure to US standards do not have a major impact on fertility values among Nigerians, particularly the desire for male children. Educated Nigerian men are an important target for population education, however, because they dominate and control many of the structural, behavioral, and cultural dimensions of fertility behavior.     

Infidelity,jealousy, and wife abuse among Tsimane forager–farmers: testing evolutionary hypotheses of marital conflict

The role of men's jealousy over a wife's infidelity in precipitating marital conflict and wife abuse is well documented. The role of women's jealousy over a husband's infidelity has received little attention, which is puzzling given high potential costs to women of withdrawal of paternal investment. We address this gap by investigating marital conflict and wife abuse among Tsimane forager–farmers of Bolivia. We test predictions derived from male jealousy and paternal disinvestment hypotheses, which consider threats and consequences of infidelity by women (male jealousy hypothesis) and men (paternal disinvestment hypothesis). The paternal disinvestment hypothesis proposes that wife abuse is employed by husbands to limit wives' mate retention effort and maintain men's opportunities to pursue extrapair sexual relationships. Interviews were conducted among husbands and wives in the same marriages using a combination of open-ended and structured items. Spouses agree that the most frequently reported type of marital argument is women's jealousy over a husband's infidelity (N=266 arguments). Roughly 60% of abusive events occurred during arguments over men's diversion of household resources (N=124 abusive events). In multivariate analyses, likelihood of wife abuse is greater in marriages where husbands have affairs, where wives are younger, and where spouses spend more time apart (N=60 husbands, 71 wives). While we find strong support for both male jealousy and paternal disinvestment hypotheses, it is men's infidelity, not women's, that precipitates most instances of marital conflict and wife abuse. We conclude that men's aggression towards their wives facilitates men's diversion of family resources for their selfish interests.     

Fertility desires of Yoruba couples of South-western Nigeria

Using the matched wife-husband (763) sample from the data collected from Ogbomoso and Iseyin towns in Oyo State, Nigeria, this paper examines factors associated with couples' fertility intention. The analysis used logistic regression models for predicting the effects of selected socioeconomic background characteristics on a couple's fertility intention. Results indicate high levels of concurrence among husbands and wives on fertility intention. Where differences exist, husbands are more pronatalists than their wives. About 87% of pairs of partners reported similar fertility preferences. Of these couples, 59.5% wanted more children while only 27.8% reported otherwise. The logistic regression models indicated that a couple's fertility intention was associated with age, education, place of residence, frequency of television-watching and number of living children. Therefore, programme interventions aimed at promoting fertility reduction in Nigeria should convey fertility regulation messages to both husbands and wives.     

Characteristics of Malignant Tumors in 230 Husband–Wife Pairs

The aim of this study is to obtain a reference point for early detection of tumors in individuals whose spouses were diagnosed with malignant tumors. Data from 230 husband and wife pairs with malignant tumors were collected and analyzed from the family history records of 15,000 people who came to the Department of Cancer Prevention, Cancer Institute/Hospital, Chinese Academy of Medical Sciences for cancer screening between January 2009 and May 2012. The median diagnosis age was 67 years for husbands and 65 years for wives. A total of 214 cases (46.5 %) had digestive system malignancies. Respiratory system cancers were diagnosed in 64 husbands, of whom 20 (31.3 %) had spouses also with respiratory system cancer. Lung cancer ranked first for the females. The total number of lung cancer and commonly seen female-specific cancers (breast, ovarian, uterine, and cervical) was 127 (55.2 %). The difference in age at diagnosis between spouses was less than 10 years in 134 couples (58.3 %), while 77 (33.5 %) couples had an age difference less than 5 years. A family history of malignant tumors in first-degree relatives was documented in 48.3 % of the husbands and 48.7 % of the wives. The occurrence of cancer in both spouses of the couples studied resulted from an interaction between genetic and environmental factors. Nonhereditary factors such as diet, smoking, passive smoking, and air pollution also contributed to the development of cancers. It is recommended that when husband is diagnosed with cancer, the wife should be screened focusing on lung, breast, and gynecological cancers. If the wife was diagnosed with malignant disease, then screening for lung and digestive system cancers should be emphasized in the husband.     

Sex-ratio biasing towards daughters among lower-ranking co-wives in Rwanda

There is considerable debate as to whether human females bias the sex ratio of their offspring as a function of their own condition. We apply the Trivers–Willard prediction—that mothers in poor condition will overproduce daughters—to a novel measure of condition, namely wife rank within a polygynous marriage. Using a large-scale sample of over 95 000 Rwandan mothers, we show that lower-ranking polygynous wives do indeed have significantly more daughters than higher-ranking polygynous wives and monogamously married women. This effect remains when controlling for potential confounds such as maternal age. We discuss these results in reference to previous work on sex-ratio adjustment in humans.     

Fishing and fertility: a study of a Nova Scotia fishing village.

The relationship between fertility and occupation is compared for: 1) deep-sea fishermen who are away from home as long as 21 days at a time with short rests between; 2) in-shore fishermen who are away at sea most nights; and 3) plant workers in the locality, used as controls. Particular attention was given to the families of fishermen who had done the same job since marriage. The population was old, relatively speaking, due to outmigration of younger people. 73% of the wives were over 30 years of age. Deep-sea fishermen are younger and have higher incomes than in-shore men (42.1 years vs 49.7 and $3544 vs $2900). Among women 15-44 years of age mean number of children for deep-sea fishermen was 3.35; in-shore, 3.60; plant workers, 3.62. Among those whose husbands had held the same job since marriage the variation was greater: deep-sea, 2.54; in-shore, 3.46; plant workers, 3.35. Among women over 45-years-old whose husbands had held the same job since marriage the number of children was 2.61, 3.94, and 4.27, respectively. 33% of plant workers had more children than desired and 66.7% said they had as many as desired. However, 25.9% of in-shore fishermen and 50% of deep-sea fishermen had fewer than desired. Interval between births was similar for all occupational groups (23.5-26.7 months) but the wives of deep-sea fishermen terminated childbearing earlier. Contraception was used only by the younger women, usually coitus interruptus or rhythm. Sterilization may have been important but it was hard to find out whether the 15% of wives who reported operations which made further childbearing impossible intended sterilization. 35.7% of deep-sea fishermens' wives reported such operations, generally women with larger families.