<p>Current theories of marriage and family formation behavior tend to rely on the assumption that people can and do consciously plan both fertility and marriage and post-hoc intentions should align with a priori reasons for action (Fishbein & Azjen 2010). However, research shows this is not always the case and researchers have labeled inconsistencies between pre- and post- reports of intentions and behavior as retrospective bias. Researchers such as Bongaarts (1990) have tried to create models that minimize this "bias".</p><p> The Theory of Conjunctural Action is a new model that can explain, rather than explain away, this "bias" (Johnson-Hanks et al. 2011; Morgan and Bachrach 2011). This new theoretical innovation uses insights about the workings of the mind to gain a greater understanding of how individuals report family formation decisions and how and why they might change over time. In this theory, individuals experience conjunctures (or social context which exists in the material world) and use cognitive schemas (or frames within the mind through which individuals use to interpret the world around them). These schemas are multiple and the set can change over time as individuals incorporate new experiences into them. </p><p> In this dissertation, I explore how and why pre- and post- reports of intentions may be different using insights from the Theory of Conjunctural Action. In the second chapter, using data from the NLSY79 and log-linear models, I show that there are considerable inconsistencies between prospective and retrospective reports of fertility intentions. Specifically, nearly 6% of births (346 out of 6022) are retrospectively reported as unwanted at the time of conception by women who prospectively reported they wanted more children one or two years prior to the birth. Similarly, over 400 births are retrospectively reported as wanted by women who intended to have no more births one or two years prior (i.e., in the prior survey wave). The innovation here is to see this inconsistency, not as an error in reporting, but as different construals of a seemingly similar question. In other words, women may not be consciously intending births and then enacting these intentions; rather women may have different schemas (or meanings) of prospective and retrospective measures of fertility intentions.</p><p> The next chapter uses this same data to test if women use different schemas to guide their reporting of prospective and retrospective fertility intentions. Again, using insights from the Theory of Conjunctural Action, I expect that different schemas (represented by different sets of variables) predict prospective and retrospective wantedness differentially. I show that retrospective reports of wantedness are guided more by age, marital status, education, job satisfaction, and educational enrollment at birth, while prospective wantedness was guided more by number of children desired and how many children they currently have. I show four logistic models predicting wanted verses unwanted births. I then compared the model fit of logistic models predicting prospective wanted verses unwanted births using the hypothesized prospective and retrospective schema variables and I did the same for the models of retrospective wantedness. I find that when women report retrospective wantedness, they are guided more by the hypothesized variables. </p><p> Finally, in the last empirical paper, because schemas are difficult to measure, I build a methodology, Network Text Analysis, to measure schemas and to understand the schemas surrounding marriage and fertility for low-income Blacks who have not yet had children. I use interview data from the Becoming Parents and Partners Study (BPP), a sample of young, unmarried, childless adults with low incomes. I use these data to explore schemas of childbearing and marriage. Contrary to previous findings that low-income parents do not link marriage and fertility and have different requirements for marriage and fertility, I find that marriage and childbearing are indeed linked and have similar requirements for low-income Blacks prior to childbearing. Low income Blacks hold quite traditional views about the role of marriage and its sequencing vis-à-vis fertility. I argue that the material constraints to marital childbearing may lead to non-marital births and thus respondents sever schemas connecting marriage and childbearing and adopt other schemas of childbearing to provide ad hoc justifications for their behavior.</p> / Dissertation

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The overall objective of this thesis was to evaluate the effects of apoptosis-like membrane and DNA changes in bull sperm, and to relate these changes to a bull’s fertility potential. This thesis hypothesis is that apoptosis-like changes occurring in fresh or cryopreserved bull sperm have a negative effect on a bull’s fertility potential. Two studies were conducted, the objectives of study 1 were to confirm the relationship of apoptosis-related membrane and nuclear changes in bull sperm with fertility, to predict the fertility of beef bulls used for natural mating; and to evaluate the effect of sperm with nicked-DNA on cleavage and blastocyst formation in vitro. In Experiment 1, phosphatidylserine (PS) translocation, from the inner to the outer plasma membrane, and DNA nicks in the sperm from 50 dairy bulls were determined using Annexin-V/PI and TUNEL assays, respectively. Relationships between the parameters of the assays and the known fertility levels of the bulls were calculated. In Experiment 2, fertility levels of 15 beef bulls used for natural mating were estimated using a regression model of DNA nicks developed in Experiment 1. In Experiment 3, the effect of DNA nicked sperm on cleavage and blastocyst rates were evaluated in in vitro produced embryos, using high and low sperm concentrations (30,000 and 300,000 sperm per IVF droplet) to fertilize the mature oocytes. In Experiment 1, there were significant relationships of fertility with live sperm (P<0.05) and necrotic sperm (P<0.01) (Annexin-V/PI assay), and with DNA-nicked sperm (P<0.001) (TUNEL assay). In Experiment 2, the fertility level of bulls used for natural breeding was estimated and ranged from -7.3 to 2.4. In Experiment 3, the cleavage rate was significantly affected by the number of sperm with nicked DNA, regardless of sperm concentration. At the low sperm concentration, blastocyst rate was significantly lower when higher DNA nicked sperm were used (51% vs 32%; high vs low DNA nicks) (P<0.05). Blastocyst rate was non significant at the higher sperm concentration regardless of DNA nicks. The second objective of this study was to evaluate the effect of apoptosis inhibitors added to post-thaw sperm samples on their longevity, to increase the availability of viable sperm to oocytes for fertilization. Frozen semen from seven bulls was used; six straws from each bull were pooled. Samples included, untreated control (sperm remaining in extender), treated control (washed sperm), and four treatments (inhibitors) each at two concentrations. Apoptosis inhibitors assessed included; Bax channel blocker, z-VAD-FMK, Coenzyme Q10, and XIAP. Motility related characteristics were evaluated using computer assisted sperm analysis (CASA). Membrane intactness and normal acrosomes were evaluated using fluorescein isothiocyanate-peanut agglutination (FITC-PNA)/propidium iodide (PI) assay. Mitochondrial membrane potential was evaluated using Mitotracker Deep Red (MtDR). Sperm parameters were evaluated at 0, 3, 6, and 12 hours of incubation. Our results showed, no significant effect of apoptosis inhibitors on post-thaw sperm motility and structural characteristics. The decline in sperm motility and structural characteristics at 6 h of incubation was lower (P<0.05) in treated control and treatment groups than untreated control group. In conclusion, the presence of nicked DNA in sperm may be used as an estimate of the fertility level of a breeding bull. The levels of sperm with DNA nicks have a negative effect on cleavage rates and subsequent blastocyst development. The second conclusion indicates that the addition of an apoptosis inhibitor post-thaw to semen samples does not improve longevity or fitness, in any of the parameters evaluated. The simple removal of extender showed to be beneficial to sperm longevity and fitness. Further studies are needed to evaluate the cleavage and blastocyst rate of embryos fertilized with a single sperm known to carry DNA nicks. As well, the effect of the addition of apoptosis inhibitors before cryopreservation of bull semen needs to be evaluated.

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This study investigates the influence of socio-economic and attitudinal factors on recent changes in marriage and fertility in Japan. Using macroand micro-data (collected especially for this research), the study examines the validity of three main theories: (1) the New Home Economics theory; (2) Easterlin's theory; and (3) the ideational (or attitudinal) theory in detemining Japanese marriage and fertility behaviour. The findings of this study show that socio-economic factors exert a substantial effect on Japanese marriage and fertility behaviour. More specifically, an increase in women's earning capacity raised their marriage age, lowered the level of their fertility, and lengthened their birth intervals. This evidence is in agreement with the New Home Economics theory. On the other hand, relative economic status also affected Japanese marriage and fertility behaviour. An improvement in the economic situation of young adults encouraged them to marry earlier, and to have more children. These findings support Easterlin's theory. However, comparing the two theories, the longitudinal trend of marriage and fertility pattern in Japan is better explained by the New Home Economics theory than Easterlin's theory. The level of women's wages had a relatively stronger impact on these patterns than their relative economic status. The findings also reveal that attitudinal factors play a significant role in determining Japanese marriage and fertility behaviour. As women became less committed to traditional norms and values, they married later, had fewer children and lengthened their birth intervals. Likewise, the reinforcement of women's individualistic attitudes raised their marriage age, lowered the level of their fertility, and delayed their entry to parenthood. This evidence indicates that marriage and fertility pattern in Japan cannot be due entirely to socio-economic factors. Comparing socio-economic and attitudinal factors, the former had a greater influence on marriage and fertility behaviour than the latter. We conclude from the findings of this study that Japanese marriage and fertility behaviour are affected both by socio-economic and attitudinal (ideational) factors, but the influence of the latter is secondary.

Declining fertility in developed countries along with rising number of immigrants and different fertility behavior exhibited by the immigrants make the immigrants’ fertility an interesting topic in field of demography. However most of the studies on immigrants’ fertility consider the female immigrants as their subject on the assumption that they represent the immigrants’ fertility. This study took another perspective and tries to study male immigrants’ fertility. Spanish Immigrants’ Survey 2007 was used to see how the different migration related factors affect the male immigrants’ fertility. Poisson regression was applied on a sample of 3797 childless males who are 16 or older. This study found tentative support to selection hypothesis but no clear support to adaptation hypothesis on male fertility behaviors. There exist differences in the fertility between male immigrants from different regions. Effect of education, number of parent’s siblings and mother language on male immigrants’ fertility was also analyzed.

Thesis (M. Phil.)--University of Hong Kong, 2007. / Also available in print.

Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 4 uppsatser.

Thesis (Ph.D.)--Australian National University, 2001.