Interpreting trends in fecundity over time

Effects of intrauterine exposure to 2,3',4,4',5-pentachlorobiphenyl on the reproductive system and sperm epigenetic imprinting of male offspring

Polychlorinated biphenyls (PCBs) are a class of persistent organic environmental pollutants with a total of 209 homologs. The homolog 2,3',4,4',5-pentachlorobiphenyl (PCB118) is one of the most important dioxin-like PCBs and is highly toxic. PCB118 can accumulate in human tissues, serum and breast milk, which leads to direct exposure of the fetus during development. In the present study, pregnant mice were exposed to 0, 20 and 100 μg/kg/day of PCB118 during the stage of fetal primordial germ cell migration. Compared with the control group, we found morphological alterations of the seminiferous tubules and a higher sperm deformity rate in the male offspring in the treatment groups. Furthermore, the methylation patterns in the treatment groups of the imprinted genes H19 and Gtl2 in the sperm were altered in the male offspring. We also characterized the disturbance of the expression levels of DNA methyltransferase 1 (Dnmt1), Dnmt3a, Dnmt3b, Dnmt3l, and Uhrf1. The results indicated that intrauterine exposure to low doses of PCB118 could significantly damage the reproductive health of the male offspring. Therefore, attention should be paid to the adverse effects of PCB118 exposure during pregnancy on the reproductive system of male offspring.

Psychological Disorders among Iranian Infertile Couples Undergoing Assisted Reproductive Technology (ART)

BACKGROUND

Worldwide, infertility affects 10%-15% of couples and most of them seek medical help including Assisted Reproductive Technology (ART) treatments. Undergoing ART treatments create many physical and emotional burdens. This study examined the psychological consequences of infertility in Iranian infertile males and females as well as their spouses, unlike previous studies that examined mainly females with infertility.

METHODS

Subjects in this descriptive analytical design were recruited from the IVF Department of Mirza Koochak Khan Hospital and the Rouyesh Infertility Treatment Center of Tehran, Iran between Aug 2014 and Sep 2015. Overall, 256 couples (64% response rate), consisting of 78 infertile male and their spouses and 50 infertile female and their spouses, were included in this research. The psychological disorders were measured by the Persian version of Symptoms Checklist-90-Revised and Cattle Inventory.

RESULTS

Psychological disorders of infertile couples are significantly associated with increasing age, higher education, longer duration of infertility and unemployment (P<0.05). Prevalence of anxiety, depression, hypochondriasis and paranoia in infertile females and spouses of infertile males were significantly higher than husbands of infertile females (P<0.05). Obsession was more sever in infertile females was significantly greater than infertile males (P=0.01). Depression was significantly lower in infertile males than their spouses (P=0.016).

CONCLUSION

Iranian infertile females and spouses of infertile males experienced more psychological disorders than infertile males and spouses of infertile females. These results may be due to the impact of cultural beliefs and gender roles in Iranian society. Anxiety, depression, obsession, paranoia and hypochondriasis should be addressed before any ART treatments.

Mental disorders in childhood and young adulthood among children born to women with fertility problems

STUDY QUESTION

Is the risk of hospital admission or outpatient contact for mental disorders increased in children born to women with fertility problems compared with children born to women without fertility problems?

SUMMARY ANSWER

We found an increased risk of hospital admission or outpatient contact for mental disorders in children born to women with fertility problems.

WHAT IS KNOWN ALREADY

Few studies have investigated the risk of mental disorders in children born after fertility treatment and although some studies have pointed to an increased risk, others found no association. The inconsistent results may be due to methodological constraints in many previous studies, including small sample size and short follow-up, resulting in imprecise risk estimates and lack of information on risk patterns of mental disorders in adulthood.

STUDY DESIGN, SIZE, DURATION

This nationwide retrospective register-based cohort study included all 2 412 721 children born in Denmark between 1969 and 2006. All children were followed from date of birth until date of hospital contact for a mental disorder, date of emigration, date of death or 31 December 2009, whichever occurred first.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Information concerning maternal fertility status for all children in the cohort was obtained by linkage to the Danish Infertility Cohort, which contains data on nearly all women with fertility problems in Denmark since 1963. A total of 124 269 (5%) children were born to women with fertility problems and 2 288 452 (95%) to women without fertility problems. To identify children hospitalized for a mental disorder, the cohort was linked to the Danish Psychiatric Central Research Registry. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between maternal fertility status and the risk of hospital admission or outpatient contact for various groups of mental disorders, including any mental disorder and all 11 main discharge diagnostic groups, classified according to the International Classification of Diseases, version 10.

MAIN RESULTS AND THE ROLE OF CHANCE

During a mean follow-up period of 21 years (range, 0-40 years), 168 686 (7%) children were admitted to hospital or had an outpatient contact for a mental disorder. Children born to women with fertility problems had a significantly higher risk of any mental disorder (HR 1.23; 95% CI 1.20-1.26) and for most of the 11 main discharge groups, including schizophrenia (HR 1.16; 95% CI 1.07-1.27), mood (affective) disorders (HR 1.21; 95% CI 1.15-1.28) and disorders of psychological development (HR 1.15; 95% CI 1.09-1.21) as well as the subgroup of attention-deficit/hyperactivity disorders (HR 1.36; 95% CI 1.29-1.45) compared with children born to women without fertility problems. The risk estimates did not change markedly when analyses were performed separately for mental disorders diagnosed during childhood (0-19 years) and in young adulthood (20-40 years).

LIMITATIONS, REASON FOR CAUTION

The true risk of mental disorders may be somewhat underestimated, as only severe disorders requiring hospital admission or outpatient contact were considered as events. Furthermore, we could not determine whether the increased risks observed were due to factors related to the underlying infertility or to fertility treatment procedures.

WIDER IMPLICATIONS OF THE FINDINGS

This is the first report on mental disorders in adulthood among children born to women with fertility problems. Furthermore, we have assessed the risk of several severe mental disorders not previously studied (e.g. neurotic, stress-related and somatoform disorders and disorders of adult personality and behaviour). These important findings should be investigated further in large epidemiological studies designed to differentiate between factors related to fertility treatment and to the underlying infertility.

STUDY FUNDING/COMPETING INTERESTS

The study was supported by internal funding from the Unit of Virus, Lifestyle and Genes at the Danish Cancer Society Research Center. All authors report no conflicts of interest.

Bisphenol-A: epigenetic reprogramming and effects on reproduction and behavior

Bisphenol A (BPA) is a synthetic compound used in the production of many polycarbonate plastics and epoxy resins. It is one of the most widely produced chemicals in the world today and is found in most canned goods, plastics, and even household dust. Exposure to BPA is almost universal: most people have measurable amounts of BPA in both urine and serum. BPA is similar in structure to estradiol and can bind to multiple targets both inside and outside the nucleus, in effect acting as an endocrine disruptor. Research on BPA exposure has accelerated in the past decade with findings suggesting that perinatal exposure to BPA can negatively impact both male and female reproduction, create alterations in behavior, and act as a carcinogen. BPA can have both short term and long term effects with the latter typically occurring through epigenetic mechanisms such as DNA methylation. This review will draw on both human and animal studies in an attempt to synthesize the literature and examine the effects of BPA exposure on reproduction, behavior, and carcinogenesis with a focus on the potential epigenetic mechanisms by which it acts.

Prevalence of infertility in the United States as estimated by the current duration approach and a traditional constructed approach

OBJECTIVE

To estimate the prevalence of infertility using a current duration approach for comparison with a traditional constructed measure.

DESIGN

Cross-sectional survey.

SETTING

Not applicable.

PATIENT(S)

A nationally representative sample of females aged 15-44 years.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Infertility prevalence estimated by two approaches: [1] a constructed measure derived from questions on sexual activity, contraception, relationship status, and pregnancy, and [2] a measure based on estimated time to pregnancy derived from the respondents' current duration of pregnancy attempt (i.e., current duration approach). Associations with self-reported descriptive characteristics using weighted logistic regression or parametric survival models for each respective approach.

RESULT(S)

Infertility prevalence was approximately twofold higher using the current duration approach (15.5%; 95% confidence interval 8.6%-27.5%) vs. the constructed measure (7.0%; 95% confidence interval 6.2%-7.8%). Both methods identified similar patterns of increasing age, lower education, nulliparity, and history of gynecologic disorders as being associated with measures of impaired fecundity, whereas opposing patterns were seen for racial/ethnic identification and poverty status.

CONCLUSION(S)

Infertility prevalence based on a current duration approach was consistent with other US prospective cohort studies with preconception enrollment. These findings underscore the importance of definition and methodologic approach for estimating the prevalence of infertility.

Psychiatric disorders in women with fertility problems: results from a large Danish register-based cohort study

STUDY QUESTION

Do women who don't succeed in giving birth after an infertility evaluation have a higher risk of psychiatric disorders compared with women who do?

SUMMARY ANSWER

The results indicated that being unsuccessful in giving birth after an infertility evaluation could be an important risk factor for psychiatric disorders.

WHAT IS KNOWN ALREADY

Several studies have investigated the association between fertility treatment and psychological distress, but the results from these studies show substantial variation and lack of homogeneity that may be due to methodological limitations.

STUDY DESIGN, SIZE AND DURATION

A retrospective cohort study was designed using data from a cohort of 98 320 Danish women evaluated for fertility problems during 1973-2008 and linked to several Danish population-based registries. All women were followed from the date of first infertility evaluation until date of hospitalization for the psychiatric disorder in question, date of emigration, date of death or 31 December 2008, whichever occurred first. Owing to the precise linkage between the infertility cohort and the Danish population-based registries, using the unique Danish personal identification number, virtually no women were lost to follow-up.

PARTICIPANTS/MATERIALS, SETTING AND METHODS

Information on reproductive status for all women in the infertility cohort was obtained by linkage to the Danish Medical Birth Registry. A total of 53 547 (54.5%) women gave birth after the initial infertility evaluation, whereas 44 773 (45.5%) women did not gave birth after the evaluation. To determine psychiatric disorders diagnosed in the women after enrolment in the infertility cohort, the cohort was linked to the Danish Psychiatric Central Registry. A total of 4633 women were hospitalized for a psychiatric disorder. The Cox proportional hazard regression model was applied to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for the association between parity status after the initial infertility evaluation and risk of hospitalization for various groups of psychiatric disorders, including 'all mental disorders' and six main discharge subgroups labelled: 'alcohol and intoxicant abuse', 'schizophrenia and psychoses', 'affective disorders', 'anxiety, adjustment and obsessive compulsive disorders', 'eating disorder' and 'other mental disorders'.

MAIN RESULTS AND THE ROLE OF CHANCE

The incidence rate for all mental disorders was 393 cases per 100 000 person-years among women who did not succeed in giving birth after the infertility evaluation but only 353 cases per 100 000 person-years among women who succeeded in giving birth after the infertility evaluation. Women not giving birth after the infertility evaluation had an increased risk of hospitalization for all mental disorders (HR 1.17, 95% CI 1.11; 1.25), alcohol and intoxicant abuse (HR 2.02, 95% CI 1.69; 2.41), schizophrenia and psychoses (HR 1.46, 95% CI 1.17; 1.82) and other mental disorders (HR 1.42, 95% CI 1.27; 1.58) compared with women who gave birth after the infertility evaluation. In contrast, the risk of affective disorders (HR 0.90, 95% CI 0.81; 0.99) was decreased among women not giving birth after the infertility evaluation. Finally, the risk of anxiety, adjustment and obsessive compulsive disorders (HR 1.07, 95% CI 0.97; 1.17) as well as of eating disorders (HR 1.40, 95% CI 0.88; 2.22) was not significantly affected by parity status after the infertility evaluation.

LIMITATIONS, REASON FOR CAUTION

As only psychiatric conditions warranting hospitalization could be included in the present study, the true incidence of all psychiatric disorders among women with fertility problems is likely to be somewhat underestimated. Furthermore, since detailed information on fertility treatment was not available for all cohort members the association between different modalities of assisted reproductive techniques and risk of psychiatric disorders was not assessed.

WIDER IMPLICATIONS OF THE FINDINGS

Clinicians and other healthcare personnel involved in diagnosis and treatment of women with fertility problems should be aware of the potential risk modification of psychiatric disorders associated with unsuccessful fertility treatment. Hence, our results may point to new aspects of follow-up of women with fertility problems who are unsuccessful in giving birth in order to prevent or identify and treat these possible psychological side effects.

STUDY FUNDING/COMPETING INTEREST(S)

The study was supported by the Danish Cancer Society (award number: 96 222 54). All authors report no conflicts of interest.

Suicide in Danish women evaluated for fertility problems

BACKGROUND

Women with fertility problems often experience higher levels of stress, anxiety and depressive symptoms associated with both the infertility diagnosis and eventual fertility treatment. The authors investigated whether women who do not succeed in having a child after an infertility evaluation are at a higher risk of suicide than women who succeed in having a child after an infertility evaluation.

METHODS

A cohort of 51 221 Danish women with primary or secondary infertility and referred to hospitals or private fertility clinics in Denmark during 1973-1998 was established. The cohort was linked to four Danish administrative population-based registries. Each woman was followed from the date of her initial fertility evaluation at the clinic or hospital until 2006. Cox proportional hazards regression analyses was used to calculate hazard ratios (HRs) for suicide and their corresponding 95% confidence intervals (CIs) adjusted for potential confounders.

RESULTS

Women who did not have a child after an initial fertility evaluation had a >2-fold (HR: 2.43; 95% CI: 1.38-3.71) greater risk of suicide than women who had at least one child after a fertility evaluation. Women with secondary infertility, i.e. women who had a child before a fertility evaluation but did not succeed in having one after, also had an increased risk for suicide (HR: 1.68; 95% CI, 0.82-3.41) compared with women who succeeded in having another child, although the risk estimate failed to reach significance.

CONCLUSIONS

Health-care personnel treating women with fertility problems should be aware of the emotional response of their patients in order to recognize and treat possible psychiatric morbidity after fertility problems.