Maternal Morbidity and Medically Assisted Reproduction Treatment Types.

Objective: To compare odds of maternal morbidity by mode of becoming pregnant and type of medically assisted reproduction treatments: fertility-enhancing drugs, intrauterine insemination (IUI), and assisted reproductive technology (ART) with autologous or donor oocytes.

Methods: Birth certificates were used to study maternal morbidity among the birthing population in Utah between 2009 and 2017 (N=469,919 deliveries); 22,543 pregnancies occurred through medically assisted reproduction (4.8%).

The midlife health of only children: chronic disease indicators and biomarkers by sibship size in three nationally representative UK cohorts.

Background: Despite persistent concerns about only children's disadvantage relative to individuals with siblings, existing health-related evidence is inconsistent. Recent evidence from Nordic countries about only children having poorer health outcomes may not apply elsewhere because selection processes differ across contexts. We investigate the midlife health of only children in the UK where one-child families tend to be socio-economically advantaged relative to large families.

Cohort Differences in Physical Health and Disability in the United States and Europe.

Objectives: Declines in mortality have historically been associated with improvements in physical health across generations. While life expectancy in most high-income countries continues to increase, there is evidence that younger generations, particularly in the United States, are less healthy than previous generations at the same age. We compared generational trends in physical health in the United States, England, and continental Europe to explore whether other regions have experienced a similar pattern of worsening health across cohorts.

Educational gradients in the prevalence of medically assisted reproduction births in a comparative perspective.

Objective: To study educational gradients in births after medically assisted reproduction across 5 countries with different institutional arrangements.

Design: We use logistic regression and compute predicted probabilities to estimate the association between education and giving birth after assisted reproduction, before and after adjustment for maternal age at delivery and marital/partnership status, using an overall sample of about 3.9 million live births in 5 countries.

Gradients in low birthweight by maternal education: A comparative perspective.

Background: Longstanding research has shown strong inequalities in low birthweight by household income. However, most such research has focused on Anglophone countries, while evidence emerging from other developed countries suggest a stronger role of education rather than incomes in creating inequalities at birth. This paper compares gradients in low birthweight by maternal education, as well as explores underlying mechanisms contributing to these gradients, in France, the United States, and the United Kingdom.

Generational differences in physical health and disability in the United States and Europe.

Objectives: Declines in mortality have typically been associated with improvements in physical health across generations. While life expectancy in most high-income countries continues to increase, there is evidence that younger generations, particularly in the United States (US), are less healthy than previous generations at the same age. We compared generational trends in physical health in the US, England, and continental Europe to explore whether other regions have experienced a similar pattern of worsening health across cohorts.

Defining and Identifying Only Children: A Research Note on the Concept and Measurement Illustrated With UK Survey Data.

Despite increasing interest in the circumstances and outcomes of only children in the demographic literature, the conceptualization of this group has received limited scholarly attention. This research note argues for greater engagement by demographers and social scientists in the conceptualization and identification of only children by addressing three aims. First, we outline potential definitions of only children, present a framework to guide researchers' decisions, and evaluate whether only children can be reliably identified using the British birth cohort studies.

Medically assisted reproduction and mental health in adolescence: evidence from the UK Millennium Cohort Study.

Background: The number and proportion of children conceived through medically assisted reproduction (MAR) is steadily increasing yet the evidence on their mental health in adolescence is inconclusive. Two main mechanisms with opposite effects can explain differences in mental health outcomes by conception mode: while more advantaged parental characteristics could positively influence it, higher parental stress could have a negative influence.

Methods: Linear and logistic estimations on a longitudinal population-based birth cohort study of 9,897 individuals to investigate whether adolescents conceived through MAR are more likely than naturally conceived (NC) children to experience mental health problems at age 17, as reported by adolescents themselves and their parents.

Partnership trajectories preceding medically assisted reproduction.

The number of people who undergo medically assisted reproduction (MAR) to conceive has increased considerably in recent decades. However, existing research into the demographics and the partnership histories of this growing subgroup is limited. Using unique data from Finnish population registers on nulliparous women born in Finland in 1971-77 ( = 21,129; ∼10 per cent of all women) who had undergone MAR treatment, we created longitudinal partnership histories from age 16 until first MAR treatment.

Loneliness during the Pregnancy-Seeking Process: Exploring the Role of Medically Assisted Reproduction.

This study explores whether undergoing medically assisted reproduction (MAR) is associated with experiencing loneliness and whether this association varies by gender and having a live birth. Using two waves of the Generations and Gender Survey (n = 2,725) from countries in Central and Eastern Europe, we estimate the changes in levels of emotional and social loneliness among pregnancy seekers in heterosexual relationships and test if they vary by the mode of conception while controlling for individual sociodemographic characteristics. Individuals who underwent MAR experienced increased levels of social loneliness compared to individuals who were trying to conceive spontaneously.

ART and the forgotten siblings: a call for research.

A broader definition of infertility is the incapacity to have the intended number of children. However, most literature on ART exclusively focuses on live birth as an outcome, rather than on the capacity to fully realize the reproductive wishes of the couples. This issue has probably received scant attention because the total fertility rate is below replacement levels in affluent countries, and one may simplistically assume that only a minority of couples may be interested in more than one child.

Sibling group size and BMI over the life course: Evidence from four British cohort studies.

Only children, here defined as individuals growing up without siblings, are a small but growing demographic subgroup. Existing research has consistently shown that, on average, only children have higher body mass index (BMI) than individuals who grow up with siblings. How this difference develops with age is unclear and existing evidence is inconclusive regarding the underlying mechanisms.

The Well-Being of Adolescents Conceived Through Medically Assisted Reproduction: A Population-Level and Within-Family Analysis.

Medically assisted reproduction (MAR) plays an increasingly important role in the realization of fertility intentions in advanced societies, yet the evidence regarding MAR-conceived children's longer-term well-being remains inconclusive. Using register data on all Finnish children born in 1995-2000, we compared a range of social and mental health outcomes among MAR- and naturally conceived adolescents in population-averaged estimates, and within families who have conceived both through MAR and naturally. In baseline models, MAR-conceived adolescents had better school performance and the likelihood of school dropout, not being in education or employment, and early home-leaving were lower than among naturally conceived adolescents.

Maternal age and the risk of low birthweight and pre-term delivery: a pan-Nordic comparison.

Background: Advanced maternal age at birth is considered a risk factor for adverse birth outcomes. A recent study applying a sibling design has shown, however, that the association might be confounded by unobserved maternal characteristics.

Methods: Using total population register data on all live singleton births during the period 1999-2012 in Denmark (N = 580 133; 90% population coverage), Norway (N = 540 890) and Sweden (N = 941 403) and from 2001-2014 in Finland (N = 568 026), we test whether advanced maternal age at birth independently increases the risk of low birthweight (LBW) (<2500 g) and pre-term birth (<37 weeks gestation).

Medically assisted reproduction and mental health: a 24-year longitudinal analysis using Finnish register data.

Background: Medically assisted reproduction can negatively affect women's mental health, particularly when the treatments do not result in a live birth. Although the number of women relying on medically assisted reproduction to conceive has grown rapidly, our knowledge about the mental health effects before, during, and after treatment is limited.

Objective: This study aimed to understand the long-term association between medically assisted reproduction and mental health outcomes for women before, during, and after their treatments, and according to whether the treatment resulted in a live birth.

Investigating change across time in prevalence or association: the challenges of cross-study comparative research and possible solutions.

Unlabelled: Cross-study research initiatives to understand change across time are an increasingly prominent component of social and health sciences, yet they present considerable practical, analytical and conceptual challenges. First, we discuss the key challenges to comparative research as a basis for detecting societal change, as well as possible solutions. We focus on studies which investigate changes across time in outcome occurrence or the magnitude and/or direction of associations.

Parental fecundability and neurodevelopmental delays and difficulties in offspring.

Background: Impaired neurodevelopment is reported among children conceived by assisted reproductive technologies (ART). However, this might be explained by conditions underlying parental subfecundity, rather than the ART procedure.

Methods: We examined associations of parental time-to-pregnancy (TTP) and conception by ART with neurodevelopmental traits up to 8 years of age, including motor and language skills, social delays and difficulties, and inattention-hyperactivity, among 92 142 singletons participating in the Norwegian Mother, Father and Child Cohort Study (MoBa).

Health outcomes of only children across the life course: An investigation using Swedish register data.

Only children (with no full biological siblings) are a growing subgroup in many high-income settings. Previous studies have largely focused on the short-term developmental outcomes of only children, but there is limited evidence on their health outcomes. Using Swedish population register data for cohorts born 1940-75, we compare the health of only children with that of children from multi-child sibling groups, taking into account birth order, family size, and presence of half-siblings.

Medically Assisted Reproduction Treatment Types and Birth Outcomes: A Between-Family and Within-Family Analysis.

Objective: To compare risks of adverse birth outcomes among pregnancies conceived with and without medically assisted reproduction treatments.

Methods: Birth certificates were used to study birth outcomes of all neonates born in Utah from 2009 through 2017. Of the 469,919 deliveries, 52.

The cognitive development from childhood to adolescence of low birthweight children born after medically assisted reproduction-a UK longitudinal cohort study.

Background: Previous research has documented that children conceived through medically assisted reproduction (MAR) are at increased risk of poor birth outcomes, such as low birthweight (LBW), which are risk factors for stunted longer-term cognitive development. However, parents who undergo MAR to conceive have, on average, advantaged socioeconomic backgrounds which could compensate for the negative effects of being born LBW. Previous studies have not analysed whether the negative effects of LBW are attenuated among MAR conceived children.

Mental Health Around the Transition to First Birth: Does Medically Assisted Reproduction Matter?

Previous research has shown that childbearing is associated with short-term improvements in women's subjective well-being but that these effects depend on the timing and quantum of the birth as well as on the parents' education and socioeconomic status. These studies did not address whether and, if so, how this effect varies according to the mode of conception. This represents an important knowledge gap, given that conceptions through medically assisted reproduction (MAR) have been increasing rapidly in recent decades, exceeding 5% of live births in some European countries.

The cognitive development from childhood to adolescence of low birthweight children born after medically assisted reproduction-a UK longitudinal cohort study.

Background: Previous research has documented that children conceived through medically assisted reproduction (MAR) are at increased risk of poor birth outcomes, such as low birthweight (LBW), which are risk factors for stunted longer-term cognitive development. However, parents who undergo MAR to conceive have, on average, advantaged socioeconomic backgrounds which could compensate for the negative effects of being born LBW. Previous studies have not analysed whether the negative effects of LBW are attenuated among MAR conceived children.

Medically assisted reproduction and parent-child relationships during adolescence: evidence from the UK Millennium Cohort Study.

Study Question: Do the parent-child relationships of adolescents born after medically assisted reproduction (MAR) using the parents' own gametes differ from those of adolescents born after natural conception (NC)?

Summary Answer: MAR and NC families have similar parent-child relationships in terms of closeness and conflict frequency, except that MAR mothers report being closer to their children than NC mothers.

What Is Known Already: Prior work on parent-child relationships during childhood has reported mixed findings. While some studies have documented no differences between MAR and NC families, others have shown that MAR families have greater levels of warmth and positive feelings than NC families.