The altered immunological status of children conceived by assisted reproductive technology

Immune profiling of ART-conceived children in Kazakhstan: a case-control study

Objective

The increasing use of assisted reproductive technologies (ART) has led to a growing interest in the health outcomes of offspring. However, the impact of ART on the immune system of children remains poorly understood. While only two publications were found, their findings contradict each other and did not consider other risk factors in their analysis except for ART use. Therefore, this study aimed to examine the potential impact of ART on the immune system of offspring.

Methods

A case-control study was conducted in Kazakhstan to investigate the immune system of ART-conceived children compared to those conceived naturally (NC). The study included participants who met certain criteria, such as having undergone a successful ART program resulting in the birth of either a single or multiple pregnancies. Patients who used donor oocytes/sperm, intrauterine insemination, or surrogacy were excluded. Anamnesis data were collected from children in both groups, and laboratory measurements were performed and analyzed using IBM SPSS Statistic 26.

Results

A total of 120 children conceived by ART and 132 NC children under the age of five were included in our study. We observed that compared with NC group, ART children had lower IgA and IgG levels (p < 0.001), absolute lymphocytosis, high levels of active T-lymphocytes (p = 0.001), and pathological T-helper levels (p = 0.004). Therefore, the clinical presentation of respiratory diseases was lower in ART group. Children born after frozen embryo transfers showed significantly higher levels of T-cytotoxic and active T-lymphocytes compared to children born after fresh embryo transfers (p = 0.007 and p = 0.020, respectively). We utilized ordinal logistic regression to control for confounding variables such as multiple pregnancy, cesarean section, premature birth, and breastfeeding. Despite this, the significant impact of ART on immunogram parameters persisted, indicating the independent and influential nature of ART or other unaccounted factors.

Exposure to polystyrene microplastics during lactational period alters immune status in both male mice and their offspring

The widespread use of microplastics and their harmful effects on the environment have emerged as serious concerns. However, the effect of microplastics on the immune system of mammals, particularly their offspring, has received little attention. In this study, polystyrene microplastics (PS-MPs) were orally administered to male mice during lactation. Flow cytometry was used to assess the immune cells in the spleens of both adult male mice and their offspring. The results showed that mice exposed to PS-MPs exhibited an increase in spleen weight and an elevated number of B and regulatory T cells (Tregs), irrespective of dosage. Furthermore, the F1 male offspring of the PS-MPs-exposed group had enlarged spleens; an increased number of B cells, T helper cells (Th cells), and Tregs; and an elevated ratio of T helper cells 17 (Th17 cells) to Tregs and T helper cells 1 (Th1 cells) to T helper cells 2 (Th2 cells). These results suggested a pro-inflammatory state in the spleen. In contrast, in the F1 female offspring exposed to PS-MPs, the changes in splenic immune cells were less pronounced. In the F2 generation of mice with exposed to PS-MPs, minimal alterations were observed in spleen immune cells and morphology. In conclusion, our study demonstrated that exposure to real human doses of PS-MPs during lactation in male mice altered the immune status, which can be passed on to F1 offspring but is not inherited across generations.

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.

Associations of childhood allergies with parental reproductive and allergy history

PURPOSE

There has been a noted parallel rise in both the use of Assisted Reproductive Technology (ART) to conceive and childhood allergies in the last few decades. The purpose of this study was to investigate the possible association between reproductive and allergy history in parents and allergies in their children.

METHODS

This exploratory study used a cross-sectional study design and web-based survey to collect anonymous data on demographics, allergy, and health history from parents and about each of their children under 18 years of age. Children were stratified into two groups by allergy status (yes/no), and associations between each variable and the odds of allergies were tested using univariable and multivariable mixed logistic regression models.

RESULTS

Of the 563 children in the study, 237 were reported to have allergies whereas 326 did not. Age, residential community, household income, mode of conception, paternal age at conception, biological parental allergy status, and history of asthma and eczema were significantly associated with allergies in univariable analysis. Multivariable analysis revealed household income ($50 k to $99 k vs ≥ $200 k adj OR = 2.72, 95% CI 1.11, 6.65), biological parental allergies (mother-adj OR 2.74, 95% CI 1.59, 4.72, father-adj OR 2.06, 95% CI 1.24, 3.41) and each additional year of age of children (adj OR 1.17, CI 1.10, 1.24) were significantly associated with odds of allergies in children.

CONCLUSION

Although the exploratory nature of this convenience, snowballing sample limited the generalizability of the findings, initial observations warrant further investigation and validation in a larger more diverse population.

[Experimental Study on the Characteristic Changes of the Immunological Microenvironment at the Maternal-Fetal Interface in IVF-ET Pregnancy]

Objective

To investigate the characteristic functional changes of the decidual natural killer (NK) cells and γδ T cells, two immunocytes in the decidua, at the maternal-fetal interface in in vitro fertilization-embryo transfer (IVF-ET) pregnancy.

Methods

Decidual samples were collected from 12 women of natural pregnancy (NP) and 32 women of IVF-ET pregnancy, who were enrolled in the NP group and the IVF-ET group, respectively. Then part of the decidual samples were paraffin-embedded for HE staining and immunofluorescence staining, while the rest of the samples were digested and Percoll was used for isolating decidual immunocytes (DICs) by gradient centrifugation. Flow cytometry was used to determine the cell counts of decidual NK cells and γδ T cells and the expression levels of their surface activation markers, CD69 and NKG2D in the NP and the IVF-ET groups. In addition, the expression levels of IFN-γ, TNF-α, IL-17A, and IL-10, the intracellular cytokines, and granzyme B, perforin, and granulysin, the cytolytic granules, were measured. The characteristic changes in the relevant immunological indicators were compared and analyzed.

Results

HE staining of the tissue specimens showed that the typical structure of decidua was observed, and that lymphocytes were enriched in the decidua. Immunofluorescence staining showed that the percentage of decidual NK (dNK) cells in nucleated cells of the IVF-ET group was significantly lower than that of the NP group ( P<0.05). Flow cytometry analysis of DICs showed that, compared with those of the NP group, the percentage of dNK cells of the IVF-ET group was decreased ( P<0.05) and the expression levels of IL-10 and perforin were significantly decreased in the IVF-ET group ( P<0.05). However, there was no significant difference in the decidual γδ T (dγδT) cell count between the two groups. The expression of IL-10, IL-17A, and perforin was downregulated in the IVF-ET group ( P<0.05). There was no significant difference in the expression of IFN-γ, TNF-α, granzyme B, and granulysin, the cellular function indicators ( P>0.05).

Conclusion

The dNK cell count and the secretion of some intracellular cytokines of dNK and dγδT cells of women of IVF-ET pregnancy decreased to some degree, which suggests that certain changes may have taken place in the immunological microenvironment at the maternal-fetal interface. The specific effect of these changes on pregnancy outcomes needs further investigation.

Effects of assisted reproductive technology on gene expression in heart and spleen tissues of adult offspring mouse

OBJECTIVES

Assisted reproductive technology (ART) is an important part of reproductive medicine, whose possible effects on offspring's health have drawn widespread attention in recent years. However, relevant studies are limited to postnatal short-term follow-up and lack of diverse sample sources analysis other than blood.

METHODS

In this study, a mouse model was used to explore the effects of ART on fetal development and gene expression in the organs of offspring in the adulthood using next-generation sequencing. The sequencing results were then analyzed.

RESULTS

The results showed that it caused abnormal expression in 1060 genes and 179 genes in the heart and spleen, respectively. Differentially expressed genes (DEGs) in the heart are mainly enriched in RNA synthesis and processing, and the cardiovascular system development also shows enrichment. STRING analysis identified Ccl2, Ptgs2, Rock1, Mapk14, Agt, and Wnt5a as the core interacting factors. DEGs in the spleen are significantly enriched in anti-infection and immune responses, which include the core factors Fos, Jun and Il1r2. Further exploration revealed the abnormal expression of 42 and 5 epigenetic modifiers in the heart and spleen, respectively. The expression of the imprinted genes Dhcr7, Igf2, Mest and Smoc1 decreased in the hearts of ART offspring, and the DNA methylation levels of Igf2- and Mest-imprinting control regions (ICRs) increased abnormally.

CONCLUSION

In the mouse model, ART can interfere with the gene expression pattern in the heart and spleen of the adult offspring and that these changes are related to the aberrant expression of epigenetic regulators.

Impact of assisted reproduction techniques on the neuro-psycho-motor outcome of newborns: a critical appraisal

Subfertility and infertility are common problems among couples of reproductive age, and they increasingly require the use of assisted reproductive techniques (ART). Understandably, doubts about the safety of such methods are increasing among future parents. The purpose of this review is to analyse the real impact of ART, such as in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI), on the health of the unborn baby; in particular, this work is focussed on the problems related to the neuro-psycho-motor area. Twenty-four studies were reviewed and outcomes investigated were: risk of the onset of neurodevelopmental diseases, worsening of school cognitive performance and risk of developing infantile cerebral palsy (CP) or neurological sequelae. For the first two outcomes, we did not find a correlation with ART; nevertheless, the results of the included studies about risk of CP are discordant and influenced by various confounding factors, such as pre-term birth and multiple pregnancies.IMPACT STATEMENTWhat is already known on this subject? Assisted reproductive techniques (ART) are the main answer for achieving pregnancy in infertile couples. However, a wide number of studies have tried to focus on possible different outcomes in terms of maternal and foetal/new-born health. Regarding this scenario, a peculiar importance is given to diseases affecting the neuro-psycho-motor area of the new-born. Since this group of detrimental pathologies could heavily affect the new-born's quality of life and require costly social facilities, different studies have tried to focus on possible outcomes after ART.What do the results of this study add? This manuscript provides a review of the literature regarding ART procedures and neuro-psycho-motor implication. A review is strongly required due to the importance of collecting evidence from studies with different methodologies.What are the implications of these findings for clinical practice and/or further research? This manuscript provides evidence about the need for wider and more congruent studies regarding neurodevelopment disorders in new-borns after ART procedures. Data are prone to suggest a slight correlation, but several confounding factors can heavily hamper the possibility to draw a firm conclusion about the topic.

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.