Asthma in children born after infertility treatment: findings from the UK Millennium Cohort Study

The risk of asthma in singletons conceived by ART: a retrospective cohort study

STUDY QUESTION

Do singleton children conceived by ART have a higher asthma risk than naturally conceived (NC) singletons?

SUMMARY ANSWER

The asthma risk was similar for ART-conceived singletons and NC singletons, and there were no clear differences between the various types of ART.

WHAT IS KNOWN ALREADY

Whether ART increases asthma risk in offspring is questionable. The evidence is inconsistent and limited by ethnicity, geographic distribution, inadequate confounder adjustment, unsatisfactory control groups, and specific methods of ART. Furthermore, the mediating effects of obstetric and neonatal outcomes on the association between ART and asthma remain unclear.

STUDY DESIGN SIZE DURATION

This observational, single-centre study was conducted at a reproductive centre of an affiliated university hospital between September 2009 and April 2023. A total of 3227 singletons aged 3-6 years conceived by IVF versus ICSI or fresh versus frozen embryo transfer were retrospectively enrolled, and a total of 1206 NC singletons of the same age were subsequently recruited.

PARTICIPANTS/MATERIALS SETTING METHODS

Asthma was defined as a self-reported physician diagnosis or wheezing in the past 12 months. We performed multivariable logistic regression analyses to examine associations between asthma in offspring and ART use, adjusting for parental characteristics (age, education level, occupation type, BMI, asthma), smoking exposure, residence type, child sex, child age, and year of follow-up. Mediating effects were explored using longitudinal mediation structural equation modelling.

MAIN RESULTS AND THE ROLE OF CHANCE

Asthma was reported for 51 (4.2%) of the 1206 NC singletons (median [interquartile range] age 5 [4-5] years; 48.1% females) and 169 (5.2%) of the 3227 ART-conceived singletons (5 [5-5] years; 47.6% females). We found that risks of childhood asthma in singletons conceived by ART were, overall, similar to those of NC singletons before (odds ratio [OR], 1.25 [95% CI, 0.92-1.74]; P = 0.170) and after adjustment (adjusted OR [aOR], 0.66 [95% CI, 0.44-1.03]; P = 0.126). The results were similar in multiple sensitivity analyses, and there were no clear differences in asthma risks according to the method of ART. Mediation analysis revealed a significant positive indirect effect of neonatal intensive care unit (NICU) admission (standard path coefficient, b = 0.025, P < 0.05) and a negative indirect effect of breastfeeding (b = -0.012, P < 0.05) on the association between ART and asthma in singleton offspring.

LIMITATIONS REASONS FOR CAUTION

This study is limited to singletons only and cannot be generalized. The study is also limited by its retrospective observational single-centre nature and sample size. Mediation analyses were exploratory. Therefore, the findings need to be interpreted with caution.

WIDER IMPLICATIONS OF THE FINDINGS

These findings can help infertile couples undergoing ART be reassured about the risk of childhood asthma in singleton offspring. Breastfeeding is recommended as a potentially feasible intervention to reduce the asthma risks in ART-conceived children who are at increased potential risk of asthma, such as those with NICU admissions.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by the Key Research and Development Program of Zhejiang Province (2021C03100), the National Key Research and Development Program of China (2021YFC2700603), and the Program for Key Subjects of Zhejiang Province in Medicine and Hygiene to Y. Z., the Zhejiang Province Natural Science Foundation (No. LQ22H040006) and the National Natural Science Foundation of China (No.82101759) to M.T., and the National Natural Science Foundation of China (No. 82201860) to J.Y. The authors declare no competing interests.

TRIAL REGISTRATION NUMBER

ChiCTR2300069906.

The Long-Term Outcome of Children Conceived Through Assisted Reproductive Technology

Assisted reproductive technology (ART) led to the birth of 60,381 infants in 2020 in Japan. This number is set to increase as the future interest in ART is anticipated to rise. Couples receiving ART are monitoring the outcomes of these treatments to see whether any differences exist between babies conceived naturally and those conceived via ART. This study investigated the relationship between the long-term outcome of children born from ART with a focus on physical and psychomotor developments. A large volume of data concerning each relationship with ART was collected from various observational studies. Several findings indicate that, over time, the physical characteristics of babies born by ART, and those born naturally are comparable. However, some reports indicate that, until they reach school age, there may be a small difference in growth. ART and naturally conceived children do not vary in academic achievement or attention deficit hyperactivity disorder. Taken together, it is difficult to conclude with certainty that ART is the source of these differences since they may arise from the child's genetic factors or their environment.

Long-term healthcare utilization and costs of babies born after assisted reproductive technologies (ART): a record linkage study with 10-years' follow-up in England

STUDY QUESTION

Is the long-term health care utilization of children born after ART more costly to the healthcare system in England than children born to mothers with no fertility problems?

SUMMARY ANSWER

Children born after ART had significantly more general practitioner (GP) consultations and higher primary care costs up to 10 years after birth, and significantly higher hospital admission costs in the first year after birth, compared to children born to mothers with no fertility problems.

WHAT IS KNOWN ALREADY

There is evidence that children born after ART are at an increased risk of adverse birth outcomes and a small increased risk of rare adverse outcomes in childhood.

STUDY DESIGN, SIZE, DURATION

We conducted a longitudinal study of 368 088 mother and baby pairs in England using a bespoke linked dataset. Singleton babies born 1997-2018, and their mothers, who were registered at GP practices in England contributing data to the Clinical Practice Research Datalink (CPRD), were identified through the CPRD GOLD mother-baby dataset; this data was augmented with further linkage to the mothers' Human Fertilisation and Embryology Authority (HFEA) Register data. Four groups of babies were identified through the mothers' records: a 'fertile' comparison group, an 'untreated sub-fertile' group, an 'ovulation induction' group, and an ART group. Babies were followed-up from birth to 28 February 2021, unless censored due to loss to follow-up (e.g. leaving GP practice, emigration) or death.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The CPRD collects anonymized coded patient electronic health records from a network of GPs in the UK. We estimated primary care costs and hospital admission costs for babies in the four fertility groups using the CPRD GOLD data and the linked Hospital Episode Statistics (HES) Admitted Patient Care (APC) data. Linear regression was used to compare the care costs in the different groups. Inverse probability weights were generated and applied to adjust for potential bias caused by attrition due to loss to follow-up.

MAIN RESULTS AND THE ROLE OF CHANCE

Children born to mothers with no fertility problems had significantly fewer consultations and lower primary care costs compared to the other groups throughout the 10-years' follow up. Regarding hospital costs, children born after ART had significantly higher hospital admission costs in the first year after birth compared to those born to mothers with no fertility problems (difference = £307 (95% CI: 153, 477)). The same pattern was observed in children born after untreated subfertility and ovulation induction.

LIMITATIONS, REASONS FOR CAUTION

HFEA linkage uses non-donor data cycles only, and the introduction of consent for data use reduced the availability of HFEA records after 2009. The fertility groups were derived by augmenting HFEA data with evidence from primary care records; however, there remains some potential misclassification of exposure groups. The cost of neonatal critical care is not captured in the HES APC data, which may cause underestimation of the cost differences between the comparison group and the infertility groups.

WIDER IMPLICATIONS OF THE FINDINGS

The findings can help anticipate the financial impact on the healthcare system associated with subfertility and ART, particularly as the demand for these treatments grows.

STUDY FUNDING/COMPETING INTEREST(S)

C.C. and this work were funded by a UK Medical Research Council Career Development Award [MR/L019671/1] and a UK MRC Transition Support Award [MR/W029286/1]. X.H. is an Australia National Health and Medical Research Council (NHMRC) Emerging Leadership Fellow [grant number 2009253]. The authors declare no competing interest.

TRIAL REGISTRATION NUMBER

N/A.

Perinatal, obstetric and parental risk factors for asthma in the offspring throughout childhood: a longitudinal cohort study

OBJECTIVES

Asthma is a common chronic and burdensome disease which typically begins in childhood. The aim of this study was to assess perinatal and obstetric factors which may increase the risk of developing asthma in the offspring.

METHODS

Data from five consecutive waves (n=7,073 children, from birth to 15 years old) from a nationally-representative birth cohort of people born in the United Kingdom between 2000 and 2002, the Millennium Cohort Study (MCS), were used. The Kaplan-Meier survival curve was used to graphically display the risk of developing asthma from early childhood to adolescence. The Z-based Wald test was used to prove significant covariate loading.

RESULTS

Cox regression analyzing the influence of covariates on asthma development risk showed a significant likelihood ratio test, χ2(18)=899.30, p<0.01. A parent with asthma (OR=2.02, p<0.01), a younger maternal age at delivery (OR=0.98, p<0.05), and the use of assisted reproductive technology (OR=1.43, p<0.05) were associated with an increased risk of developing asthma in the offspring.

CONCLUSIONS

Perinatal factors (a younger maternal age, assisted reproductive technology) and a parental factor (a parent with asthma) increased the risk for developing asthma in the offspring.

Long-Term Effects of ART on the Health of the Offspring

Assisted reproductive technologies (ART) significantly increase the chance of successful pregnancy and live birth in infertile couples. The different procedures for ART, including in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), intrauterine insemination (IUI), and gamete intrafallopian tube transfer (GIFT), are widely used to overcome infertility-related problems. In spite of its inarguable usefulness, concerns about the health consequences of ART-conceived babies have been raised. There are reports about the association of ART with birth defects and health complications, e.g., malignancies, high blood pressure, generalized vascular functional disorders, asthma and metabolic disorders in later life. It has been suggested that hormonal treatment of the mother, and the artificial environment during the manipulation of gametes and embryos may cause genomic and epigenetic alterations and subsequent complications in the health status of ART-conceived babies. In the current study, we aimed to review the possible long-term consequences of different ART procedures on the subsequent health status of ART-conceived offspring, considering the confounding factors that might account for/contribute to the long-term consequences.

Gestational and health outcomes of dairy cows conceived by assisted reproductive technologies compared to artificial insemination

Herd gestation and health management are key aspects of effective dairy farm operations and animal welfare improvement. Unfortunately, very little is known about the developmental divergences induced by assisted reproduction technologies (ART) and their consequences once the animal is mature. Indeed, the gestational and health outcomes of this subset of the Holstein population is yet to be characterized. In this study, the intergenerational impacts of ART conception were assessed by looking at the gestation and health outcomes of a large cohort of cows (n = 284,813) for which the conception methods were known. Our results showed that cows conceived by multiple ovulation embryo transfer (MOET) and in vitro fertilisation (IVF) displayed longer gestations: +0.37 ± 0.079 and +0.65 ± 0.21 day compared to cows conceived by artificial insemination (AI). Surprisingly, animals conceived by all methods experienced a similar 1-day decline in average gestation length from 2012 to 2019. Cows conceived by IVF were not more likely to experience stillbirths but were affected by common diseases such as ovarian cysts, mastitis, and uterine diseases in different proportions compared to cows conceived by other methods. This study provides new and unique information on ART animals regarding perinatal mortality and general health outcomes.

General health in a cohort of children conceived after assisted reproductive technology in the United Kingdom: a population-based record-linkage study

BACKGROUND

Assisted reproductive technology use is increasing annually; however, data on long-term child health outcomes including hospital admissions are limited.

OBJECTIVE

This study aimed to examine the potential effects of assisted reproductive technology on any and cause-specific hospital admissions unrelated to perinatal diagnoses.

STUDY DESIGN

This was a population-based record-linkage study that included a previously established cohort of children born after assisted reproductive technology in the United Kingdom between 1997 and 2009 (n=63,877), their naturally conceived siblings (n=11,343), and matched naturally conceived population controls (n=127,544) linked to their postnatal health outcomes up to March 31, 2016 to provide robust risk estimates of the potential effects of assisted reproductive technology on any and cause-specific hospital admissions unrelated to perinatal diagnoses. In addition, comparison of hospital admissions by type of treatment was made. Cox regression was used to estimate the risk of hospital admission, and negative binomial regression was used to compare the number of hospital admissions per year.

RESULTS

This study had 1.6 million person-years of follow-up (mean, 12.9 years; range, 0-19 years), and the mean age at the time of first hospital admission was 6.5 years (range, 0-19 years). Singletons born after assisted reproductive technology had increased risk of any hospital admission compared with naturally conceived population controls (hazard ratio, 1.08; 95% confidence interval, 1.05-1.10) but not naturally conceived siblings (hazard ratio, 1.01; 95% confidence interval, 0.94-1.09). We observed increased risk of diagnoses related to neoplasms and diseases of the respiratory, musculoskeletal, digestive, and genitourinary systems, and lower risk of injury, poisoning, and consequences of external causes compared with naturally conceived population controls. Children born after intracytoplasmic sperm injection had a lower risk of hospital admission compared with those born after in vitro fertilization, although no such differences were observed between children born after fresh embryo transfers and those born after frozen embryo transfers.

CONCLUSION

Children born after assisted reproductive technology had greater numbers of hospital admissions compared with naturally conceived population controls. Attenuation of these differences in relation to their naturally conceived siblings suggested that this could be partially attributed to the influence of parental subfertility on child health, increased parental concerns, and an actual increase in morbidity in children born after assisted conception.

The association between hypertensive disorders of pregnancy and childhood asthma

BACKGROUND

Asthma is a chronic long-term inflammatory disease of the airways and is a major global health challenge. The primary aim of this study was to investigate the association between hypertensive disorders of pregnancy (HDP) and the risk of asthma at or before the age of seven years using the UK Millennium Cohort Study (MCS).

METHODS

Overall, 18,552 families were recruited for wave one of the MCS when the child was 9 months old, and subsequently participated in waves two, three and four when they were three, five and seven years respectively. HDP were self-reported by mothers in wave one. The primary outcome was a parent-reported diagnosis of "ever asthma" at seven years, based on responses to a validated questionnaire.

RESULTS

Following adjustment for a range of potential confounding factors, HDP was found to be associated with asthma in the offspring (adjusted odds ratio (AOR 1.35; 95% CI: 1.15-1.59)). A larger effect estimate was observed amongst children exposed to HDP and born preterm (AOR 1.81; 95% CI: 1.25-2.61) or small for gestational age (SGA) (AOR = 1.58; (95% CI: 1.15-2.18)).

CONCLUSIONS

In conclusion, children exposed to HDP may be at increased odds of asthma diagnosis by age seven, particularly if they were born preterm or SGA.

IMPACT

There is a paucity of data investigating the relationship between hypertensive disorders of pregnancy and childhood asthma, with recent studies showing conflicting results. Our study investigated this relationship using a large cohort with ample information on a wide range of confounding factors. Our study showed that individuals exposed to HDP may be at increased odds of asthma diagnosis by age seven years, particularly if they were also born SGA or preterm.

Health of singletons born after frozen embryo transfer until early adulthood: a Finnish register study

STUDY QUESTION

Is the health of singletons born after frozen embryo transfer (FET) comparable to that of singletons born after fresh embryo transfer (ET) until early adulthood?

SUMMARY ANSWER

The health of singletons born after FET does not differ from that of singletons born after fresh ET.

WHAT IS KNOWN ALREADY

The differences in perinatal outcomes of children born after FET and fresh ET are well known. FET is associated with an increased risk of large-for-gestational-age but diminished risks of preterm birth (PTB), small-for-gestational-age and decreased perinatal mortality compared to fresh ET. However, knowledge on the long-term health after FET is scarce.

STUDY DESIGN, SIZE, DURATION

This retrospective register-based cohort study compares singletons born after FET (n = 1825) between the years 1995 and 2006 to those born after fresh ET (n = 2933) and natural conception (NC, n = 31 136) with a mean follow-up time of 18-20 years.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Singletons born after FET were compared to those born after fresh ET and NC regarding the frequencies of diagnoses in the main ICD-10 chapters (International Statistical Classification of Diseases and Related Health Problems, 10th revision), the number of outpatient visits and hospital admissions, and mortality. Adjustments were made for PTB, maternal age, parity, socioeconomic status based on mother's occupation and offspring sex. The study combines data from the Finnish Medical Birth Register, the Finnish Care Register for Health Care (CRHC) and the Cause-of-Death Register at Statistics Finland. The Student's T-test was used for continuous variables, and the Chi-square test was used for categorical variables. Cox regression was used to estimate crude and adjusted hazard ratios (HRs and aHRs, respectively). A general linear model was used to compare the means of outpatient visits, hospital admissions and lengths of hospital stays per person.

MAIN RESULTS AND THE ROLE OF CHANCE

No significant differences between the FET and fresh ET groups were found in the frequency of diagnoses in any of the ICD-10 chapters or in the parameters describing the need for hospital care. However, compared to the NC group, higher proportions in the FET group had outpatient visits in the hospital (93.5% vs 92.2%, aHR 1.23, 95% CI 1.17, 1.30) or hospital admissions (48% vs 46.5%, aHR 1.28, 95% CI 1.19, 1.37). Compared to the NC group, the FET group had elevated adjusted risks of diagnoses of infectious and parasitic diseases (aHR 1.24; 95% CI 1.11, 1.38), neoplasms (aHR 1.68; 95% CI 1.48, 1.91), diseases of the eye and adnexa, the ear or mastoid process (aHR 1.11; 95% CI 1.01, 1.21), the respiratory system (aHR 1.15; 95% CI 1.06, 1.23), the digestive system (aHR 1.17; 95% CI 1.05, 1.32), the skin or subcutaneous tissue (aHR 1.28; 95% CI 1.14, 1.43) and the genitourinary system (aHR 1.27; 95% CI 1.11, 1.45), as well as congenital malformations or chromosomal abnormalities (aHR 1.31; 95% CI 1.14, 1.50) and symptoms, signs or abnormal clinical or laboratory findings (aHR 1.25, 95% CI 1.16, 1.34).

LIMITATIONS, REASONS FOR CAUTION

Only hospital-based inpatient and outpatient care is covered by the CRHC register, excluding milder cases diagnosed elsewhere. We were not able to study the effect of ART treatments and subfertility separately in our setting. In addition, although our cohort is reasonably sized, even larger cohorts would be needed to reliably study rare outcomes, such as cancer.

WIDER IMPLICATIONS OF THE FINDINGS

For many ICD-10 chapters, we present the first published data on the long-term outcome of singletons born after FET. The results on FET versus fresh ET are reassuring, whereas the results on FET versus NC warrant further investigation.

STUDY FUNDING/COMPETING INTEREST(S)

Finnish government research funding was obtained for this study. Funding was also obtained from the Finnish Medical Society Duodecim, the Päivikki and Sakari Sohlberg Foundation, Orion Research Foundation, Finnish Society of Obstetrics and Gynaecology (research grants to A.M.T.) and Finnish government research funding. The funding sources were not involved in the planning or execution of the study. The authors have no competing interests to declare.

TRIAL REGISTRATION NUMBER

N/A.

Early childhood respiratory tract infections according to parental subfertility and conception by assisted reproductive technologies

STUDY QUESTION

Are children conceived by ART or born to subfertile parents more susceptible to upper or lower respiratory tract infections (URTI, LRTI)?

SUMMARY ANSWER

ART-conceived children had a higher frequency of and risk of hospitalization for respiratory infections up to age 3, which was only partly explained by parental subfertility.

WHAT IS KNOWN ALREADY

Some studies report increased risks of infections in children conceived by ART. Results for URTIs and LRTIs are inconclusive, and the contribution of underlying parental subfertility remains unclear.

STUDY DESIGN, SIZE, DURATION

We included 84 102 singletons of the Norwegian Mother, Father and Child Cohort Study (MoBa) born between 1999 and 2009. Mothers reported time-to-pregnancy at recruitment and child history of, frequency of and hospitalization for, respiratory infections when the child was 6, 18 and 36 months old by questionnaires. Subfertility was defined as having taken 12 or more months to conceive. The Medical Birth Registry of Norway (MBRN) provided information on ART. URTI included throat and ear infections, while LRTI included bronchitis, bronchiolitis, respiratory syncytial virus and pneumonia.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We used log-binomial regression to estimate risk ratios (RR) and 95% CI of any respiratory tract infection and hospitalization, and negative-binomial regression to calculate incidence rate ratios (IRR) and 95% CI for number of infections. We compared children conceived by ART, and naturally conceived children of subfertile parents, to children of fertile parents (<12 months to conceive) while adjusting for maternal age, education, BMI and smoking during pregnancy and previous livebirths. We accounted for dependency between children born to the same mother.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 7334 (8.7%) singletons were naturally conceived by subfertile parents and 1901 (2.3%) were conceived by ART. Between age 0 and 36 months, 41 609 (49.5%) of children experienced any URTI, 15 542 (18.5%) any LRTI and 4134 (4.9%) were hospitalized due to LRTI. Up to age 3, children conceived by ART had higher frequencies of URTI (adjusted IRR (aIRR) 1.16; 95% CI 1.05–1.28) and hospitalizations due to LRTI (adjusted RR (aRR) 1.25; 95% CI 1.02–1.53), which was not seen for children of subfertile parents. Children conceived by ART were not at higher risks of respiratory infections up to age 18 months; only at age 19–36 months, they had increased risk of any LRTI (aRR 1.16; 95% CI 1.01–1.33), increased frequency of LRTIs (IRR 1.22; 95% CI 1.02–1.47) and a higher risk of hospitalization for LRTI (aRR 1.35; 95% CI 1.01–1.80). They also had an increased frequency of URTIs (aIRR; 1.19; 95% CI 1.07–1.33). Children of subfertile parents only had a higher risk of LRTIs (aRR 1.09; 95% CI 1.01–1.17) at age 19–36 months.

LIMITATIONS, REASONS FOR CAUTION

Self-reported time-to-pregnancy and respiratory tract infections by parents could lead to misclassification. Both the initial participation rate and loss to follow up in the MoBa limits generalizability to the general Norwegian population.

WIDER IMPLICATIONS OF THE FINDINGS

ART-conceived children might be more susceptible to respiratory tract infections in early childhood. This appears to be only partly explained by underlying parental subfertility. Exactly what aspects related to the ART procedure might be reflected in these associations need to be further investigated.

STUDY FUNDING/COMPETING INTEREST(S)

Funding was received from the Swiss National Science Foundation (P2BEP3_191798), the Research Council of Norway (no. 262700), and the European Research Council (no. 947684). All authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Assisted reproductive technology and childhood morbidity: a longitudinal cohort study

OBJECTIVE

To evaluate the association between assisted reproductive technology (ART) and offspring morbidity in the first decade of life.

DESIGN

Longitudinal cohort study.

SETTING

Provincial health registry in Quebec, Canada.

PATIENT(S)

A total of 797,654 singleton children born between 2008 and 2019, followed up to 2020.

INTERVENTION(S)

Retrospective, noninterventional study of any ART procedure vs. no ART.

MAIN OUTCOME MEASURE(S)

Childhood morbidity, including hospitalization for infectious, allergic, malignant, and other diseases, assessed using adjusted Cox proportional hazards regression to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) for the association with ART. We controlled for unmeasured family-level confounders that were shared among siblings through stratified Cox regression. To do so, we restricted the analysis to 10,097 siblings with discordant exposure to ART and compared the risk of outcomes in exposed vs. unexposed siblings.

RESULT(S)

Compared with no ART, ART was associated with 1.23 times the risk of any hospitalization (95% CI 1.19-1.27), 1.25 times the risk of infectious disease hospitalization (95% CI 1.21-1.29), and 1.25 times the risk of allergy hospitalization (95% CI 1.14-1.38). When we used a sibling design to control for shared genetic and environmental confounders, ART was not associated with a greater risk of childhood hospitalization (HR 0.92, 95% CI 0.78-1.08).

CONCLUSION(S)

ART is associated with an elevated risk of hospitalization up to 11 years of age, but discordant sibling analysis suggests that the association may be due to genetic, environmental, or other shared familial confounders.

Therapeutic importance of Zishen Yutai Pill on the female reproductive health: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Zishen Yutai Pill (ZYP) is a widely used Traditional Chinese Medicine in Assisted Reproductive Technology (ART) medications, particularly in China. ZYP has a potential therapeutic role in human reproductive health, including in vitro fertilization embryo transfer and various reproductive disorders. The National Essential Medicine List of China has recently included the ZYP in Obstetrics and Gynecology medicine due to its significance in treating miscarriage and fertility associated disorders. Various clinical studies have demonstrated the importance of ZYP in improving the fertility and pregnancy rate. However, the pharmacological and toxicological actions of ZYP on reproductive health has been scantly reported.

AIM OF THE REVIEW

This review aims to emphasize the potential therapeutic effect of ZYP in ART and highlight its clinical significance in treating various reproductive disorders linked with hormonal balance, ovarian follicle development, menstrual cycle, uterine function and pregnancy. Additional insights on the safety evaluation of ZYP were elucidated by exploring an array of published experimental studies in various animal models with its molecular mechanism of action.

MATERIALS AND METHODS

The literature review was conducted across the databases such as PubMed, ScienceDirect, Google Scholar, China Biomedical Literature Database, China National Knowledge Infrastructure, Wanfang Database, International Clinical Trials Registry Platform and Cochrane Central Register of Controlled Trials with no time limit applied. The search terms used in this review include, 'Zishen Yutai Pills' and/or 'reproduction', 'assisted reproductive techniques', 'pregnancy', 'threatened abortion', 'miscarriage', 'fertility', 'infertility', 'disorders', 'women health', 'toxicity', and 'adverse effects'.

RESULTS

ZYP is a combination of fifteen traditional medicines and each of its components has various biological functions in humans. ZYP has improved the fertility and pregnancy rate through in vitro fertilization-embryo transfer. Further, various clinical studies have revealed that ZYP showed the curative effect for miscarriage, recurrent spontaneous abortion, menstrual disorder, luteal dysfunction, diminished ovarian reserve, polycystic ovary syndrome and premature ovarian insufficiency. The intervention of ZYP has multiple roles in reproductive functions such as regulation of ovulation, follicle development, menstrual flow, hormonal balance and endometrial thickness. The reproductive and toxicological reports in various animal models have highlighted the efficacy and safety of ZYP on the reproductive functions.

CONCLUSION

Nowadays, many problems are associated with maternal health, fertility and reproduction, due to the various physiological and environmental factors. The intervention of ART provides hope to infertile patients. Overall, this review provides insights on the therapeutic importance of ZYP in ART medications and treating various reproductive disorders.

The altered immunological status of children conceived by assisted reproductive technology

BACKGROUND

With the increased use of assisted reproductive technology (ART), assessing the potential health risks of children conceived on ART important to public health. Most research in this area has focused on the effects of ART on perinatal, metabolic, and oncological risks in children. Although an increased risk of immune-related diseases has been reported in children born after ART, there are no studies on the immunological status of these children. This study aimed to evaluate the impact of different embryo transfer methods and fertilization strategies on the immune status of the offspring.

METHODS

A total of 69 children born to women treated with ART and a matched control group of 17 naturally conceived (NC) children, all aged from 3 to 6 years, were recruited in the reproductive hospital affiliated to Shandong University. The frequency of immune cells in the peripheral blood was assayed using flow cytometry; plasma cytokine levels were determined by multiplex cytokine immunoassay with human cytokine magnetic beads.

RESULTS

Compared to children born after natural conception, children born after ART had elevated interferon-γ (IFN-γ) levels, regardless of embryo transfer and fertilization strategies. Children in the fresh-embryo transfer group had significantly higher IL-4 levels and a lower ratio of IFN-γ to IL-4 than those in the NC group ((P = 0.004, 10.41 ± 5.76 pg/mL vs 18.40 ± 7.01 pg/mL, P = 0.023, 1.00 ± 0.48 vs 0.67 ± 0.32, respectively). Similar results were shown in either the in vitro fertilization (IVF) group or the intra-cytoplasmic sperm injection (ICSI) group (P < 0.05 and P = 0.08 for IVF; P < 0.05 and P < 0.05 for ICSI, respectively). These alterations in IL-4 concentrations and the ratio of IFN-γ to IL-4 were statistically significantly correlated with supra-physical E₂ (estradiol) levels on the day of hCG administration (R = 0.502, P = 0.017; R = - 0.537, P = 0.010, respectively). Consistently, the frozen embryo transfer did not result in alterations of these immune indicators in the offspring. Overall, there were no significant differences between the ART group and NC group in the frequencies of T cells, B cells, natural killer (NK) cells, CD4⁺T cells, CD8⁺T cells, T helper (T_H)1 cells, T_H17 cells, and regulatory T (T_reg) cells and cytokine levels of IL-10 and IL-17a (all P > 0.05).

CONCLUSIONS

Immunological alterations existed in children born after the use of ART. The elevated E₂ levels before embryo implantation contributed to the increased IL-4 levels in children conceived by fresh embryo transfer. The assessment of immunological alteration is of importance to children conceived by ART for early monitoring and intervention.

Asthma and allergies in offspring conceived by ART: a systematic review and meta-analysis

BACKGROUND

Currently, 1 in 25 children born in Australia are conceived through ARTs such as IVF and ICSI. Worldwide over 8 million children have been born after ART. There is evidence that these children are at an increased risk of congenital malformations, preterm birth, low birth weight and neonatal morbidity. However, studies on long-term health outcomes of offspring conceived after ART are lacking. Atopic disorders, such as asthma, atopic dermatitis and various allergies are increasingly common within society, and concerns have been raised that ART increases the risk of atopy amongst offspring.

OBJECTIVE AND RATIONALE

The aim of this study was to systematically summarise and quantify the risk of atopic disorders in offspring conceived with ART compared to those conceived without ART.

SEARCH METHODS

A systematic review was conducted according to the PRISMA guidelines. Several systematic searches were performed in the following international databases: Medline, Embase, Cinahl, PsychINFO, AMED, Global Health and ISI Web of Science. Search terms utilised were all terms pertaining to ART, IVF, ICSI, asthma, atopic dermatitis and allergies. The search period was 1978-2021. Included observational studies stated a primary outcome of asthma or allergies in offspring conceived after ART, with a comparison group conceived without ART. Individual studies were scored on quality and risk of bias, using the Newcastle-Ottawa scale (NOS).

OUTCOMES

There were 26 studies which met the inclusion criteria; of these, 24 studies investigated asthma in offspring conceived after ART. While 10 studies, including the two largest population-based studies, reported a significantly increased risk of asthma in offspring conceived after ART (adjusted odds ratio (aOR) range: 1.20-2.38), 14 smaller cohort studies found no difference (aOR range 0.70-1.27). In the meta-analysis of the 14 highest-quality studies (NOS ≥ 7), a modest yet significantly increased risk of asthma was demonstrated in offspring conceived after ART [risk ratio (RR) 1.28 (1.08-1.51)]. Although heterogeneity in these 14 studies was high (I2 = 85%), the removal of outliers and high weight studies significantly reduced heterogeneity (I2 = 0% and I2 = 34% respectively) while still demonstrating a significantly increased risk [RR 1.19 (1.10-1.28) and RR 1.31 (1.03-1.65), respectively]. The increased asthma risk was also observed in most subgroup and sensitivity analyses. The allergy rates were not increased in offspring conceived after ART in 9 of 12 studies (aOR range 0.60-1.30). In summary, the findings of this systematic review and meta-analysis suggest a trend towards a significantly increased risk of asthma, but not allergies, in offspring conceived after ART. There was no evidence of publication bias in the asthma studies and minimal evidence of publication bias in the allergy studies (both P > 0.05).

WIDER IMPLICATIONS

Asthma brings considerable burden to the quality of life of individuals and to society. Hence, it is of great importance to untangle potential causal pathways. Although ART use is common, knowledge about its long-term health effects is required to provide evidence-based advice to couples considering ART, and to be vigilant for any potential adverse health effects on offspring conceived after ART.

Association between childhood asthma and history of assisted reproduction techniques: a systematic review and meta-analysis

Genetic and environmental factors during early development may influence lung growth and impact lung function. We performed a meta-analysis of epidemiological studies examining the association between conception history of assisted reproduction techniques (ART) and childhood asthma. We searched PubMed and Embase up to November 2020 for relevant observational studies and synthesized data data under a fixed or random effects model as appropriate. Heterogeneity was assessed using the I² metric. We identified 13 individual studies including 3,226,386 participants. We did not observe a statistically significant association between ART and physician-diagnosed asthma (n = 9, random OR 1.16; 95% CI 0.94-1.43; I² 61%). We observed a statistically significant association between ART and prescription of asthma medications (n = 6, fixed OR 1.27; 95% CI 1.23-1.32; I² 0%). Wheezing was also associated with ART (n = 4, fixed OR 1.71; 95% CI 1.08-2.72; I² 0%). When we combined studies using any asthma definition, a statistically significant association was observed (random OR 1.19; 95% CI 1.05-1.34; I² 80%).Conclusion: The available observational evidence suggests that the risk of asthma is higher among children born after ART. The mechanism and potential sources of bias behind this association are under scrutiny, and further work is needed to establish causality. What is Known: • "Positive" epidemiological signals for the association between assisted reproduction techniques and asthma stemming from large studies were not replicated by subsequent research. • Any available research synthesis effort so far bears no quantitative aspect. What is New: • The available observational evidence suggests that the risk of asthma is higher among children born after ART. • The mechanism and potential sources of bias behind this association are under scrutiny.

Long-Term Disturbed Expression and DNA Methylation of SCAP/SREBP Signaling in the Mouse Lung From Assisted Reproductive Technologies

Assisted reproductive technology (ART) has been linked to cholesterol metabolic and respiratory disorders later in life, but the mechanisms by which biosynthetic signaling remain unclear. Lung inflammatory diseases are tightly linked with the sterol regulatory element-binding protein (SREBP) and SREBP cleavage-activating protein (SCAP), but this has not been shown in an ART offspring. Here, mouse models from a young to old age were established including in vitro fertilization (IVF), intracytoplasmic injection (ICSI), and in vivo fertilized groups. In our results, significantly higher plasma levels of CRP, IgM, and IgG were identified in the aged ICSI mice. Additionally, pulmonary inflammation was found in four aged ART mice. At three weeks, ART mice showed significantly downregulated levels of Scap, Srebp-1a, Srebp-1c, and Srebf2 mRNA in the lung. At the same time, significant differences in the DNA methylation rates of Scap-Srebfs and protein expression of nuclear forms of SREBPs (nSREBPs) were detected in the ART groups. Only abnormalities in the expression levels of Srebp-1a and Srebp-1c mRNA and nSREBP1 protein were found in the ART groups at 10 weeks. However, at 1.5 years old, aberrant expression levels and DNA methylation of SCAP, SREBP1, and SREBP2, and their associated target genes, were observed in the lung of the ART groups. Our results indicate that ART increases long-term alterations in SCAP/SREBP expression that may be associated with their aberrant methylation status in mouse.

Health and Well-Being Outcomes of Adolescents Conceived Through In Vitro Fertilization and Intracytoplasmic Sperm Injection

What is the perception of health and well-being of adolescents from an assisted reproductive technology (ART) cohort? We conducted a survey, from September 2015 to June 2016, through self-completion questionnaires, on 487 singleton or twin ART-conceived 11- to 15-year-old adolescents, followed up since 1994, as part of an ART cohort. Collected data concerned perinatal characteristics, health indicators and perception, eating habits, behavior, and living standards. A total of 60.6% of the questionnaires were returned and could therefore be analyzed. This concerned 295 adolescents who were representative of the 788 remaining adolescents of our cohort, in terms of type of ART, maternal and perinatal characteristics, but not gender (sex ratio = 0.77). Overall, 15.3% reported chronic diseases, and only 13.3% of them considered that their chronic disease had an impact on their school life. Moreover, 94.2% of adolescents perceived that their health was "excellent" or "good"; 97.3% adolescents had normal weight or were underweight; onset of menstruation was 12 years old (± 1) for girls, age usually reported for puberty in girls; 51.9% declared having regular physical activity, boys more frequently than girls. Moreover, 70.6% of the boys had a sedentary behavior compared to 44.8% of the girls. A total of 73.5% of the adolescents were stressed at school, but school demand was considered high only in 12.2% of cases. Finally, 90% declared to have high life satisfaction. Overall, ART does not appear to have particular effect on the health indicators and behavior of adolescents who participated in the survey except for higher family affluence scale.

Assisted reproductive technology and long-term ophthalmic morbidity of the offspring

In this study, we investigate if children born following assisted reproduction technologies (ARTs) are at an increased risk for long-term ophthalmic complications. For this purpose, a population-based cohort analysis was conducted which included all deliveries between 1991 and 2014 at a single tertiary medical center. Offspring were classified relative to conception method as ART or spontaneous pregnancies. Offspring hospitalizations up to the age of 18 years involving ophthalmic morbidities were evaluated according to a predefined set of ICD-9 codes. A Kaplan-Meier survival curve was used to compare cumulative hospitalization rates in exposed (ART) and unexposed offspring (spontaneous), and a Cox proportional hazards model was used to control for potential confounders. A total of 243,682 deliveries were included in the study. In that, 1.8% of the deliveries (4364) were of mothers who underwent fertility treatments and 98.2% (239,318) were conceived spontaneously. Offspring born to mothers who underwent fertility treatments had a significantly higher hospitalization rate involving ophthalmic morbidity, as compared to spontaneously conceived offspring (1.2% vs. 1.0%, p = 0.04). The Kaplan-Meier survival curve pointed to a significantly higher cumulative incidence of ophthalmic morbidity following ART (log rank p = 0.02). Cox proportional hazards model was adjusted for maternal age, preterm delivery, maternal hypertensive disorders, diabetes, and mode of delivery which demonstrated ART as an independent risk factor for long-term pediatric ophthalmic morbidity (adjusted hazard ratio = 1.37, CI 1.04-1.80, p-value = 0.02). We concluded that ART is an independent risk factor for long-term ophthalmic morbidity of the offspring.

Health outcomes in offspring born to survivors of childhood cancers following assisted reproductive technologies

PURPOSE

An increasing number of childhood cancer survivors are using assisted reproductive technologies (ART) to overcome treatment-related fertility impairment. We report perinatal and health outcomes of offspring born to survivors following ART.

METHODS

The FeCt Multicenter Offspring Study surveyed the health of offspring of childhood cancer survivors. Health outcomes in offspring born to survivors following ART (n = 57, 4.6%) or after spontaneous conception (n = 1182) were assessed in the German cohort (n = 1239) using bivariate analysis. Findings were put into the context of the general German population by health outcome assessment in 1:1 matched-pair analysis (n = 2478).

RESULTS

Nearly twice the survivors used ART compared with numbers reported for the German general population (4.6% vs. 2.6%). Successful pregnancies were achieved after a median of two cycles, mainly using non-cryopreserved oocytes/sperm. Multiple sibling births (p < 0.001, 28.1% vs. 3.0%) and low birth weight (p = 0.008; OR = 2.659, 95% CI = 1.258-5.621) occurred significantly more often in offspring born to survivors who utilized ART than spontaneously conceived children, whereas similar percentages were born preterm or too small for their gestational age. ART did not increase the prevalence of childhood cancer or congenital malformations in offspring born to survivors.

CONCLUSION

ART use by childhood cancer survivors was successful with both fresh and cryopreserved oocytes/sperm, and did not influence perinatal health or health outcomes when known confounders were taken into account.

IMPLICATIONS FOR CANCER SURVIVORS

Oncofertility is an important component of patient care. Our study implicates that the utilization of ART by adult survivors of childhood cancer does not put offspring at additional risk for adverse perinatal or health outcomes.

Analysis of maternal and perinatal determinants of allergic sensitization in childhood

Background

Non-communicable diseases, such as allergies, are influenced by both genetic and epigenetic factors. Perinatal determinants conceivably modify the epigenetic makeup of the developing fetal immune system preventing or predisposing the development of allergies. The aim of this study therefore was to identify independent perinatal factors associated with allergic sensitization in childhood.

Methods

In a single center retrospective case-cohort study electronic obstetric medical records and available skin prick testing results of children were analyzed. For the analysis 286 skin prick test positive (sensitized) children [median (IQR): 3.47 (1.70–7.34) years] were compared with data from all remaining live births in the obstetric cohort (n = 66,583).

Results

Sensitized children more frequently had a mother born in Asia (19.1% vs. 10.2%; P < 10–6). Applying backward elimination logistic regression, seven out of 23 initially entered perinatal factors remained in the model. High maternal age (> 35 years; OR: 1.912; P < 0.001), male offspring sex (OR: 1.423; P < 0.01) and assisted conception (OR: 1.771; P < 0.05) increased the risk for allergic sensitization. In contrast, maternal smoking (OR: 0.469; P < 0.005), increasing parity (OR: 0.881; P < 0.05), maternal pre-pregnancy overweight (OR: 0.742; P < 0.005) and preterm birth (OR: 0.484; P < 0.05) decreased the risk for allergic sensitization.

Conclusions

In addition to supporting previous findings, this study is first to report an increased risk of allergic sensitization after assisted conception. Beyond this finding’s potential implementation in preventative strategies, exploration of this association could further pathophysiological understanding of allergic disease.

Fertility treatments and offspring pediatric infectious morbidities: results of a population-based cohort with a median follow-up of 10 years

OBJECTIVE

To study the association between mode of conception and offspring infectious morbidity risk.

DESIGN

Population-based cohort study.

SETTING

Regional university medical center.

PATIENT(S)

All singleton infants born between the years 1991 and 2014 and discharged alive from the hospital.

INTERVENTION(S)

Follow-up time in the study was calculated from birth to an event, defined as the first offspring hospitalization with any infectious morbidity. All infectious diagnoses were compared between the study groups, and a multivariable survival model was created to study the association between mode of conception and offspring pediatric hospitalization with infectious morbidity, and adjusting for confounding or clinically significant variables.

MAIN OUTCOME MEASURE(S)

First offspring pediatric hospitalization with infectious morbidity.

RESULT(S)

During the study period, 242,187 newborns met the inclusion criteria: 2,603 (1.1%) of which were conceived after undergoing IVF, 1,172 (0.7%) after ovulation induction (OI), and 237,863 (98.3%) were conceived spontaneously. Mothers receiving fertility treatments were older and with higher rates of preterm births and low birthweights. The hospitalizations rates per 1,000 person years of follow-up were 16.34/1,000 person years, 11.61/1,000 person years, and 10.19/1,000 person years, among the IVF, OI, and spontaneously conceived offspring, respectively. The adjusted hazard ratios were 1.26 (95% confidence interval 1.13-1.42) and 1.14 (95% confidence interval 1.00-1.38), for the IVF and OI compared with the spontaneously conceived offspring, respectively. The model adjusted for preterm delivery, birthweight, maternal age, hypertension, diabetes, and cesarean section.

CONCLUSION(S)

Higher risk for infectious morbidity was found among offspring conceived after fertility treatments compared with spontaneously conceived offspring.

Fertility treatments and gastrointestinal morbidity of the offspring

BACKGROUND

Prevalence of pregnancies conceived following fertility treatments is high worldwide. While the impact of fertility treatments on short-term perinatal outcome is well established, long-term consequences are yet to be determined.

OBJECTIVE

To study the association between mode of conception and long-term gastrointestinal morbidity among children born following fertility treatments.

STUDY DESIGN

A population-based cohort analysis including all singleton deliveries occurring between 1991 and 2014 at a single regional tertiary medical center was performed. Fetuses with congenital malformations were excluded. A comparison was performed between children delivered following IVF, OI and spontaneous pregnancies. Hospitalizations up to the age of 18 years involving gastrointestinal morbidity were evaluated. Kaplan-Meier survival curve was used to compare cumulative morbidity incidence. A Cox regression model was used to control for confounders.

RESULTS

During the study period 242,187 singleton deliveries met the inclusion criteria; 1.1% following IVF (n = 2603), and 0.7% following OI (n = 1721). Hospitalization rates involving gastrointestinal morbidity were significantly higher in children conceived following IVF and OI (5.7%, 7.1% respectively) as compared with children conceived spontaneously (5.4%; p = 0.005). The Kaplan-Meier survival curve demonstrated a significantly higher cumulative incidence of gastrointestinal morbidity following IVF and OI (log rank p = 0.001). Using a Cox proportional hazards model, controlling for maternal age, preterm delivery, birthweight, maternal diabetes and hypertensive disorders in pregnancy, IVF (adjusted HR = 1.27, CI 1.08-1.50, p = 0.004), was noted as an independent risk factor for long-term pediatric gastrointestinal morbidity.

CONCLUSION

Singletons conceived by IVF appear to be at an increased risk for long-term gastrointestinal morbidity.

Long-term health of children conceived after assisted reproductive technology

The aim of this narrative review is to summarize the present knowledge on long-term outcome of children born after assisted reproductive technologies (ART). The main outcomes covered are neurodevelopment including cerebral palsy, cognitive development, attention deficit hyperactivity disorder and autism spectrum disease, growth, cardiovascular function, diabetes type 1, asthma, malignancies, and reproductive health. Results have mainly been obtained from systematic reviews/meta-analyses and large registry studies. It has been shown that children born after ART, when restricted to singletons, have a similar outcome for many health conditions as their spontaneously conceived peers. For some outcomes, particularly cardiovascular function and diabetes, studies show some higher risk for ART singletons or subgroup of ART singletons. The fast introduction of new ART techniques emphasizes the importance of continuous surveillance of children born after ART.

Altered TH1, TH2, TH17 balance in assisted reproductive technology conceived mice

AIM AND PURPOSE

The higher prevalence rate of different diseases may accentuate the possible alteration of the immune system in individuals conceived through the assisted reproductive technologies (ART). The present study was conducted to evaluate the TH1, TH2, TH17 balance in intracytoplasmic sperm injection (ICSI) and in vitro fertilization (IVF) - conceived mice in comparison to naturally conceived offspring.

METHODS

Mice (6-8 weeks) were divided into three groups (IVF- conceived, ICSI- conceived and naturally conceived). They were subjected to subcutaneous immunization witMycobacterium bovis Bacille Calmette-Guérin (BCG). The blood samples were taken and the sera were separated. Then the spleens were surgically removed at the time the mice were sacrificed. Serum levels of IFN-γ, IL-17A and IL-4 were detected by ELISA. Then the proportion of TCD4 cells possessing the T-bet+, GATA3+, and ROR-γt + were measured using FACS caliber flow cytometer.

RESULTS

In comparison with naturally conceived mice, intracellular expression of T-bet and serum levels of IFN-γ were significantly decreased in ART- conceived mice. Moreover, ART- conceived offspring showed marked increase in IL-4 and IL-17A.

CONCLUSION

It is concluded that compared to naturally conceived male mice, ART- conceived counterparts exhibit less efficient immune responses against BCG through further promotion of humoral and inflammatory related immune response characteristics.

Fertility treatments and the risk of pediatric obstructive sleep apnea in the offspring-Results from a population-based cohort study

OBJECTIVE

While the impact of fertility treatments on the perinatal outcome is well established, the long-term effects on offspring are yet to be determined. The current study aimed to investigate the risk of long-term obstructive sleep apnea (OSA) among children born following in vitro fertilization (IVF) and ovulation induction (OI) as compared with spontaneously conceived pregnancies.

STUDY DESIGN

A retrospective population-based cohort study was performed. Exposure was defined as delivery following pregnancies conceived by IVF or OI. Incidence of OSA related hospitalizations of the offspring, up to the age of 18 years, was evaluated. A Kaplan-Meier survival curve and multivariable Cox regression models were used to assess the association.

RESULTS

During the study period, 242 187 singleton deliveries met the inclusion criteria; 1.1% were conceived following IVF (n = 2603), and 0.7% following OI (n = 1721). Offspring hospitalization rates, involving OSA (n = 1607), were higher among children conceived following IVF and OI pregnancies as compared with the rate in children conceived spontaneously (1.4% vs 1.2% vs 0.7%, respectively; P < .001). The Kaplan-Meier survival curve demonstrated a significantly higher cumulative incidence of OSA related hospitalizations following IVF and OI (log-rank P < .001). Using multiple Cox regression models, controlled for gestational age, maternal age, maternal smoking, maternal obesity, birthweight, offspring gender and obesity, IVF as well as OI exhibited a significant and independent association with pediatric OSA in all models with adjusted hazard ratios of 2.25, (95% confidence interval [CI] = 1.6-3.1) and 1.63 (95% CI = 1.1-2.5), respectively.

CONCLUSION

Both IVF and OI treatments appear to be independently associated with OSA in the offspring.

Assisted reproductive technologies are associated with limited epigenetic variation at birth that largely resolves by adulthood

More than 7 million individuals have been conceived by Assisted Reproductive Technologies (ART) and there is clear evidence that ART is associated with a range of adverse early life outcomes, including rare imprinting disorders. The periconception period and early embryogenesis are associated with widespread epigenetic remodeling, which can be influenced by ART, with effects on the developmental trajectory in utero, and potentially on health throughout life. Here we profile genome-wide DNA methylation in blood collected in the newborn period and in adulthood (age 22–35 years) from a unique longitudinal cohort of ART-conceived individuals, previously shown to have no differences in health outcomes in early adulthood compared with non-ART-conceived individuals. We show evidence for specific ART-associated variation in methylation around birth, most of which occurred independently of embryo culturing. Importantly, ART-associated epigenetic variation at birth largely resolves by adulthood with no direct evidence that it impacts on development and health.

Use of Assisted Reproductive Technologies (ART) is increasing globally but their impact on long term health remains unclear. Here the authors show that ART-conceived individuals show variation in epigenetic profile at birth that largely resolves by adulthood, with no evidence of an impact on long term outcomes.

Outcomes of preterm infants conceived with in vitro fertilization

OBJECTIVES

To determine if there is increased risk of prematurity-related complications for in vitro fertilization (IVF)-conceived preterm infants compared to matched controls.

STUDY DESIGN

Cohort study of 23-34 weeks' preterm infants from 329 US NICUs discharged from 2009 to 2016. Each IVF patient was matched to three controls.

RESULTS

We identified 6,756 IVF-conceived preterm infants who were matched with 20,268 controls. IVF-conceived infants had no increase in non-respiratory morbidities but had significantly higher rates of bronchopulmonary dysplasia (8.4% vs 7%, p < 0.001) and significantly greater exposure to common chronic respiratory medications.

CONCLUSIONS

In this large cohort of IVF-conceived preterm infants we found similar outcomes to controls with the exception of bronchopulmonary dysplasia and respiratory medication exposure. Further research is needed to explore the influence of in vitro fertilization on the development of neonatal respiratory disease.

Health of adults aged 22 to 35 years conceived by assisted reproductive technology

OBJECTIVE

To determine the health outcomes for adults aged 22-35 years old who were conceived via assisted reproduction technology (ART) compared with adults of the same age conceived without use of ART.

DESIGN

Cohort study.

SETTING

Not applicable.

PATIENT(S)

Adult men and women aged 22-35 years who were conceived with and without use of ART.

INTERVENTION(S)

Questionnaire and clinical review.

MAIN OUTCOME MEASURE(S)

Vascular structure (carotid artery intima-media thickness, pulse wave velocity), vascular function (blood pressure), metabolic markers (fasting blood glucose, insulin, and standard lipid profiles), anthropometric measurements, and respiratory function (spirometry).

RESULT(S)

The mean age of the 193 ART and 86 non-ART participants was 27.0 and 26.9 years, respectively. There were no substantial intragroup differences in demographics or vascular intermediate phenotypes, metabolic parameters, or anthropometric measures, before or after adjusting for perinatal factors and a quality of life measure with four domains. Diastolic blood pressure was lower in the ART men than the non-ART men (adjusted mean difference -4.4 mm Hg, 95% CI, -8.7 to -0.1). The ART group reported a higher prevalence of ever having asthma, (40.8% vs. 28.6%; odds ratio 1.7; 95% CI, 1.0-3.0), but expiratory flow rates were similar.

CONCLUSION(S)

This study of the health of 193 adults conceived via ART, the largest to date globally, found no evidence of increased vascular or cardiometabolic risk, or growth or respiratory problems in the ART group compared with a non-ART group from the same source population. Follow-up observation for reproductive and later-onset adverse health effects remains important.

Child Health: Is It Really Assisted Reproductive Technology that We Need to Be Concerned About?

Concerns remain about the health of children conceived by infertility treatment. Studies to date have predominantly not identified substantial long-term health effects after accounting for plurality, which is reassuring given the increasing numbers of children conceived by infertility treatment worldwide. However, as technological advances in treatment arise, ongoing studies remain critical for monitoring health effects. To study whether the techniques used in infertility treatment cause health differences, however, remains challenging due to identification of an appropriate comparison group, heterogeneous treatment, and confounding by the underlying causes of infertility. In fact, the factors that are associated with underlying infertility, including parental obesity and other specific male and female factors, may be important independent factors to consider. This review will summarize key methodological considerations in studying children conceived by infertility treatment including the evidence of associations between underlying infertility factors and child health.

Maternal history of miscarriages and measures of fertility in relation to childhood asthma

BACKGROUND

It remains unclear what underlies the greater risk of asthma reported among children conceived by assisted reproductive technologies (ART).

OBJECTIVE

Our aim was to clarify the role of parental subfertility and unmeasured confounding on the association between ART and childhood asthma, and to examine the possibility for common mechanisms underlying parental subfertility and miscarriages influencing asthma pathogenesis.

METHODS

We used data from national Norwegian health registries (n=474 402) and the Norwegian Mother and Child Cohort Study (MoBa) (n=75 797). We used log-linear regression to estimate overall associations, and fixed-effects logistic regression to estimate associations within siblings.

RESULTS

ART offspring had greater asthma risk, the adjusted relative risk (aRR) was 1.20 (95% CI 1.09 to 1.32) in the registry-based cohort, and 1.42 (95% CI 1.14 to 1.76) in MoBa. The sibling analysis yielded similar associations, although the CI included the null value. The elevated asthma risk among ART offspring was attenuated when they were compared with spontaneously conceived offspring with time to conception >12 months, aRR 1.22 (95% CI 0.95 to 1.57). Asthma risk also increased with maternal history of early miscarriages (≤12 weeks), with an aRR of 1.07 (95% CI 1.03 to 1.11) for one, aRR 1.18 (95% CI 1.10 to 1.26) for two and aRR 1.24 (95% CI 1.12 to 1.37) for three or more.

CONCLUSION

Our findings indicate that both parental subfertility and characteristics related to the ART procedure itself might increase offspring asthma risk, although this needs to be confirmed in future studies, and further suggest that common mechanisms underlying parental subfertility and recurrent miscarriages might influence offspring asthma pathogenesis.

Long-Term Cardiovascular Morbidity in Children Born Following Fertility Treatment

OBJECTIVE

To determine the risk of long-term cardiovascular disease (CVD) among children born following in vitro fertilization (IVF) and compared with spontaneous pregnancies.

STUDY DESIGN

A population-based cohort study including all singleton deliveries occurring between 1991and 2014 at a tertiary medical center was performed. Hospitalizations up to the age of 18 years involving CVD were evaluated in children delivered following IVF, ovulation induction, and spontaneous pregnancies. CVD included valvular disorders, hypertension, arrhythmias, rheumatic disease, cardiomyopathy, ischemic heart disease, and heart failure. Kaplan-Meier survival curves were used to compare cumulative morbidity incidence, and a Cox regression model controlled for confounders.

RESULTS

During the study period, 242 187 singleton deliveries met the inclusion criteria; 1.1% following IVF (n = 2603), and 0.7% following ovulation induction (n = 1721). Hospitalizations up to the age of 18 years involving CVD (n = 1503) were comparable in children delivered following IVF (0.6%), ovulation induction (0.7%), and spontaneous pregnancies (0.6%; P = .884). No significant difference in the cumulative incidence of CVD was noted between the groups (log rank P = .781). Controlling for maternal age, gestational age, birthweight, maternal diabetes, and hypertensive disorders in pregnancy, fertility treatment was not noted as a risk factor for long-term pediatric CVD (IVF adjusted hazard ratio 1.05, 95% CI 0.63-1.74, P = .86; ovulation induction adjusted hazard ratio 0.97, CI 95% 0.55-1.71, P = .92).

CONCLUSIONS

Singletons conceived via fertility treatments do not appear to be at an increased risk of long-term pediatric CVD.

Asthma in 9-year-old children of subfertile couples is not associated with in vitro fertilization procedures

Asthma is a chronic reversible obstructive airway disease, which is common among children and leads to respiratory impairment. Studies showed that asthma is more common among children born after in vitro fertilization (IVF) than among spontaneously conceived children. However, it is unknown which component of the IVF procedure contributes to this putative link. Therefore, the aim of this prospective follow-up study was to differentiate the possible effect of ovarian hyperstimulation from that of the in vitro culture procedure on asthma and rhinitis in 9-year-old children conceived with IVF. The study comprised three groups of singletons: (I) conceived with ovarian hyperstimulation-IVF (COH-IVF, n = 95); (II) conceived with modified natural cycle-IVF (MNC-IVF, n = 48); and (III) naturally conceived to subfertile couples (Sub-NC, n = 68). Parents filled out the validated Dutch version of the asthma questionnaire of the International Study of Asthma and Allergies. Asthma prevalence in the groups did not differ: COH-IVF n = 8 (8%); MNC-IVF n = 0 (0%); and Sub-NC n = 4 (6%). Adjustment for confounders did not alter the results.Conclusion: Neither ovarian hyperstimulation nor the in vitro culture procedure was associated with asthma and rhinitis at 9 years. IVF children had a similar prevalence of asthma compared with children conceived naturally by subfertile couples.Trial registration: ISRCTN76355836 What is Known: • An increased risk for asthma has been observed in children born after in vitro fertilization at preschool and school age. • The association between IVF and asthma may be partly explained by parental subfertility. What is New: • IVF children do not have a higher prevalence of asthma than children of subfertile couples conceived naturally. • Ovarian hyperstimulation used in IVF is not associated with asthma in 9-year-old children of subfertile couples.

Gestational age at birth and wheezing trajectories at 3-11 years

OBJECTIVE

Children born preterm have an increased risk of asthma in early childhood. We examined whether this persists at 7 and 11 years, and whether wheezing trajectories across childhood are associated with preterm birth.

DESIGN

Data were from the UK Millennium Cohort Study, which recruited children at 9 months, with follow-up at 3, 5, 7 and 11 years.

OUTCOMES

Adjusted ORs (aOR) were estimated for recent wheeze and asthma medication use for children born <32, 32-33, 34-36 and 37-38 weeks' gestation, compared with children born at full term (39-41 weeks) at 7 (n=12 198) and 11 years (n=11 690). aORs were also calculated for having 'early-remittent' (wheezing at ages 3 and/or 5 years but not after), 'late' (wheezing at ages 7 and/or 11 years but not before) or 'persistent/relapsing' (wheezing at ages 3 and/or 5 and 7 and/or 11 years) wheeze.

RESULTS

Birth <32 weeks, and to a lesser extent at 32-33 weeks, were associated with an increased risk of wheeze and asthma medication use at ages 7 and 11, and all three wheezing trajectories. The aOR for 'persistent/relapsing wheeze' at <32 weeks was 4.30 (95% CI 2.33 to 7.91) and was 2.06 (95% CI 1.16 to 2.69) at 32-33 weeks. Birth at 34-36 weeks was not associated with asthma medication use at 7 or 11, nor late wheeze, but was associated with the other wheezing trajectories. Birth at 37-38 weeks was not associated with wheeze nor asthma medication use.

CONCLUSIONS

Birth <37 weeks is a risk factor for wheezing characterised as 'early-remittent' or 'persistent/relapsing' wheeze.

Evaluation of prooxidant-antioxidant balance in in vitro fertilization-conceived mice

Objective

Concerns about the safety of assisted reproductive technology (ART) have been raised, as some studies have shown elevated incidence rates of childhood cancer, asthma, allergies, and other diseases in ART-conceived babies. Findings regarding the health of ART-conceived babies are controversial. The present study was conducted to evaluate the prooxidant-antioxidant balance (PAB) in in vitro fertilization (IVF)-conceived mice in comparison to naturally conceived offspring.

Methods

Mice (6-8 weeks) were divided into two groups (IVF-conceived and naturally conceived) matched by sex, age, weight, and litter size. A 1-mL blood sample was taken and the sera were separated. The oxidant-antioxidant balance was evaluated using a fast and reliable PAB assay. The results were expressed as mean±standard deviation.

Results

The mean PAB values (HK units) in the IVF-conceived and naturally conceived groups were 59.70±22.30 and 54.70±18.22, respectively (p=0.82).

Conclusion

Since free radicals contribute to several pathological conditions and antioxidants play an important protective role against oxidative stress, evaluating the oxidant-antioxidant balance is very important. Although the results of this study showed that the quality of the defense mechanism against free radicals was not significantly different between the IVF-conceived and naturally conceived mice, other parameters of metabolic dysfunction need to be measured.

Intracytoplasmic sperm injection: state of the art in humans

Among infertile couples, 25% involve both male and female factors, while male factor alone accounts for another 25% due to oligo-, astheno-, teratozoospermia, a combination of the three, or even a complete absence of sperm cells in the ejaculate and can lead to a poor prognosis even with the help of assisted reproductive technology (ART). Intracytoplasmic sperm injection (ICSI) has been with us now for a quarter of a century and in spite of the controversy generated since its inception, it remains in the forefront of the techniques utilized in ART. The development of ICSI in 1992 has drastically decreased the impact of male factor, resulting in millions of pregnancies worldwide for couples who, without ICSI, would have had little chance of having their own biological child. This review focuses on the state of the art of ICSI regarding utility of bioassays that evaluate male factor infertility beyond the standard semen analysis and describes the current application and advances in regard to ICSI, particularly the genetic and epigenetic characteristics of spermatozoa and their impact on reproductive outcome.

Clinical review of 24-35 year olds conceived with and without in vitro fertilization: study protocol

Background

Children conceived by assisted reproductive technologies (ART) currently comprise 4% of Australian births. The manipulation of biological parameters related to fertilization and implantation are integral to successful ART but potentially pose a risk to the longer-term health of the offspring. There is consensus that many common adult health problems (particularly cardiovascular, metabolic and respiratory conditions) have their origins in early life, possibly before birth, and that risk trajectories track through childhood until clinical disease manifests in adulthood. Early life epigenetic variation may play a role in this process. However little is known about the long-term health of individuals conceived by ART. In a previous study, based on telephone-interviews, we found that young adults conceived by in vitro fertilization (IVF) had significantly more maternal reported atopic respiratory, endocrine, nutritional, and metabolic conditions than non-IVF conceived matched controls. Here we outline the protocol for a follow-up biomedical assessment of this cohort and a questionnaire to obtain information on potential confounders.

Methods

We are conducting a clinical review of an existing, well characterised cohort comprising 547 IVF-conceived adults and 549 matched controls. We are measuring cardiovascular intermediate phenotypes, metabolic parameters and respiratory function, complemented by epigenome-wide DNA methylation analysis. A pilot study demonstrated the feasibility of our proposed protocol and its acceptability to participants. Participants attend a 2–3 h clinical assessment and complete a study-specific online questionnaire. Measurements include: 1) cardiovascular phenotypes: carotid artery intima-media thickness and distensibility, retinal vascular calibre, resting blood pressure, pulse wave velocity and pulse wave analysis; 2) respiratory function: spirometry, plethysmography, multiple breath washout; 3) auxology: height, weight, waist circumference, bio-impedance. Blood is collected for 4) biomarkers of cardiometabolic profile including inflammatory markers and 5) epigenetic analysis.

Discussion

Recruitment for this clinical review is challenging as many of the participants have moved to regional, interstate or international locations. Additionally, many female participants are pregnant or breastfeeding, and are therefore ineligible. Nevertheless, comprehensive strategies have been developed to optimize recruitment. Given the increasing use of IVF and related technologies, the potential long-term consequences for risk of common adult diseases is an important clinical and public health issue.

Health and functioning of adolescents conceived by assisted reproductive technology

OBJECTIVE

To evaluate the general health, mental health, and cognitive ability of assisted reproductive technology (ART)-conceived adolescents.

DESIGN

A nested case-control study within a historic cohort.

SETTING

Not applicable.

PATIENT(S)

A total of 253 ART-conceived adolescents born between 1982 and 1993 and 253 matched references according to birth year, gender, and the high-school they attended.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Medical and psychiatric diagnoses, and cognitive ability recorded at the military preinduction screening (ages 16-17 years) and doctor's appointments throughout the military service.

RESULT(S)

No differences were detected in general and mental health of ART adolescents or cognitive ability, compared with the reference group. Similar results were obtained after stratification for gender and singleton births. The ART adolescents had fewer cases of discharge from military service due to health reasons (4% vs. 8.3%). Follow-up during the military service revealed that male ART adolescents had significantly more doctor's appointments compared with the reference group (23.80 ± 15.59 vs. 19.95 ± 13.79).

CONCLUSION(S)

Our preliminary results provide reassurance that in the long-run health and functioning of ART-conceived adolescents is not compromised. Further studies with larger cohorts are needed to confirm these results.

Assisted reproductive technology and risk of asthma and allergy in the offspring: protocol for a systematic review and meta-analysis

INTRODUCTION

The use of assisted reproductive technology (ART) procedures has increased globally over the last three decades. Recent observational studies suggest that children conceived through ART may be at increased risk of asthma and atopic disease compared with children conceived naturally, but findings are mixed. We aim to synthesise the evidence on the impact of ART on the risk of asthma and atopic disease in the offspring.

METHODS AND ANALYSIS

We will identify relevant studies by searching MEDLINE, EMBASE, Cochrane Library, ISI Web of Science, CINAHL, Scopus, Google Scholar, AMED, Global Health, PsychINFO, CAB International and the WHO Global Health Library from 1978 to 2016. We will locate additional studies through searching databases of the proceedings of international conferences, contacting international experts in the field, and searching the references cited in identified studies. We will include analytic observational studies (cohort studies, case-control studies and cross-sectional studies) that have investigated the impact of any type of ART on offspring's asthma and atopic disease. Screening of identified records, data extraction from eligible studies and risk of bias assessment of eligible studies will be independently undertaken by two reviewers, with arbitration by a third reviewer. The Effective Public Health Practice Project will be employed for risk of bias assessment. Estimates from studies judged to be clinically, methodologically and statistically homogeneous will be synthesised using random-effects meta-analysis.

ETHICS AND DISSEMINATION

As this study is based solely on the published literature, no ethics approval is required. We will publish our findings in a peer-reviewed scientific journal and present the results at national and international scientific conferences.

PROTOCOL REGISTRATION

We will register a detailed protocol for the review with the International Prospective Register of Systematic Reviews (PROSPERO) prior to starting the review.

Social inequalities in wheezing in children: findings from the UK Millennium Cohort Study

Wheezing in childhood is socially patterned, but it is unclear what factors explain the social differences.Regression analysis of the UK Millennium Cohort Study, based on 11 141 singleton children who participated at ages 9 months and 3, 5 and 7 years. Relative risk ratios (RRR) for early and persistent/relapsing wheeze were estimated using multinomial regression, according to measures of socioeconomic circumstances. Maternal, antenatal and early-life characteristics were assessed as potential mediators.Children of mothers with no educational qualifications were more likely to have both wheeze types, compared to children of mothers with degree-level qualifications (RRR 1.53, 95% CI 1.26-1.86 for early wheeze; 1.32 95% CI 1.04-1.67 for persistent/relapsing wheeze). Controlling for maternal age, smoking during pregnancy and breastfeeding removed the elevated risk of wheezing. Male sex, maternal age, body mass index, atopy, smoking during pregnancy, preterm birth, breastfeeding, exposure to other children and furry pets were independently associated with wheezing, but the pattern of association varied between wheezing types.In this representative UK cohort, adjustment for maternal smoking during pregnancy and breastfeeding removed the socioeconomic inequalities in common wheezing phenotypes. Policies to reduce the social gradient in these risk factors may reduce inequalities in wheezing and asthma.

Asthma and asthma medication use among 4-year-old offspring of subfertile couples--association with IVF?

This study evaluated the prevalence of asthma and asthma medication use in 213 4-year-old singletons followed from birth onwards, including three groups of children born following: (i) controlled ovarian hyperstimulation IVF/intracytoplasmic sperm injection (ICSI); (ii) modified natural cycle IVF/ICSI; and (iii) natural conception in subfertile couples. The rate of asthma medication was higher in the ovarian hyperstimulation-IVF/ICSI than in the subfertile group (adjusted odds ratios [aOR]: 1.96 [1.00-3.84]). Time to pregnancy, a proxy for the severity of subfertility, was not associated with asthma and asthma medication. In conclusion, controlled ovarian hyperstimulation-IVF/ICSI is associated with the use of asthma medication in 4-year-old offspring of subfertile couples.

Prenatal exposure to H2 blockers and to proton pump inhibitors and asthma development in offspring

Fetal exposure to H2 blockers (H2 Bs) or proton pump inhibitors (PPIs) has been reported to be associated with asthma in children. We evaluated the risk of asthma in offspring following prenatal H2 Bs. We enrolled 91 428 children and their mothers who resided in southern Israel during 1998-2011. The computerized medications database was linked with records from the district hospital. Of the eligible children, 11 227 developed asthma, and overall 5.5% had been exposed to H2 Bs or PPIs prenatally. The risk of developing asthma was slightly higher in the group exposed to H2 Bs or PPIs (RR, 1.09; P = .023). At greater risk were children whose mothers purchased these medications more than 3 times (RR, 1.22; P = .038) or exposed to >20 defined daily doses or prenatally exposed to lansoprazole. The statistical association was significant and depended on magnitude of exposure and specific medication, but the absolute risk was low. The association between maternal consumption of H2 Bs or PPIs and asthma and childhood remained statistically significant 2 years after delivery, raising the possibility of confounding by the indication phenomenon. In view of the findings, a causal relationship could not be ascertained, and an unidentified etiological factor could be operative.

Assisted reproductive technology and somatic morbidity in childhood: a systematic review

OBJECTIVE

To assess whether children conceived by assisted reproductive technology are at increased risk of somatic morbidity in childhood compared with spontaneously conceived children.

DESIGN

Systematic review.

SETTING

None.

PATIENT(S)

Children conceived by assisted reproductive technology and reference groups of spontaneously conceived children or children from the background population.

INTERVENTION(S)

Medline/Pubmed, Embase, and the Cochrane Library were searched as well as reference lists of the retrieved relevant studies. Only cohort studies and case-control studies were included. All studies were scored using the Newcastle-Ottawa scale to assess study quality and the risk of bias in the individual studies.

MAIN OUTCOME MEASURE(S)

Postneonatal somatic diseases, health care use, chronic illnesses (unspecified), surgery, use of medication, and mortality.

RESULT(S)

Thirty-eight studies were included. Results indicated that children conceived by assisted reproductive technology may be at increased risk of unspecified infectious and parasitic diseases, asthma, genitourinary diseases, epilepsy or convulsions, and longer hospitalizations. However, several results in individual studies were not statistically significant and some inconsistency existed between study results. No differences between groups were found regarding hospital admission, outpatient visits, or use of medication. Results regarding mortality, unspecified cancer, pneumonia, allergy, respiratory, and gastrointestinal diseases were contradictory. When considering only the 13 studies allocated the highest score on the Newcastle-Ottawa scale, similar results were found.

CONCLUSION(S)

Children conceived by assisted reproductive technology may be at increased risk of somatic morbidity in childhood compared with spontaneously conceived children, although some inconsistency exists between study results.

The risk of neurodisability and other long-term outcomes for infants born following ART

Children born after assisted reproductive technologies (ART) have an increased morbidity. The risk of developing cerebral palsy is nearly doubled and the risk of developing epilepsy is also higher. Behavioural problems including attention deficit/hyperactivity disorder may be more common in children born following ART than among naturally conceived children but the finding is uncertain. Data on autism are difficult to interpret. There may exist a small increase in the incidence of childhood cancer and there is greater evidence of an elevated risk of asthma. To some extent, these risks are mediated by neonatal complications including prematurity and low birth weight but some effects such as cerebral palsy are likely to be linked to the increased rate of multiple births after ART. Many of the neonatal complications after ART are most likely linked to parental subfertility and are less an effect of the ART technology. The possibility exists that imprinting errors, associated with subfertility and/or ART, may result in long-term morbidity.