Influence of paternal age on ongoing pregnancy rate at eight weeks' gestation in assisted reproduction

Advanced Paternal Age in Focus: Unraveling Its Influence on Assisted Reproductive Technology Outcomes

As global demographics shift toward increasing paternal age, the realm of assisted reproductive technologies (ARTs), particularly in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), faces new challenges and opportunities. This study provides a comprehensive exploration of the implications of advanced paternal age on ART outcomes. Background research highlights the social, cultural, and economic factors driving men toward later fatherhood, with a focus on the impact of delayed paternity on reproductive outcomes. Methods involve a thorough review of existing literature, centering on changes in testicular function, semen quality, and genetic and epigenetic shifts associated with advancing age. Study results point to intricate associations between the father's age and ART outcomes, with older age being linked to diminished semen quality, potential genetic risks, and varied impacts on embryo quality, implantation rates, and birth outcomes. The conclusions drawn from the current study suggest that while advanced paternal age presents certain risks and challenges, understanding and mitigating these through strategies such as sperm cryopreservation, lifestyle modifications, and preimplantation genetic testing can optimize ART outcomes. Future research directions are identified to further comprehend the epigenetic mechanisms and long-term effects of the older father on offspring health. This study underscores the need for a comprehensive approach in navigating the intricacies of delayed fatherhood within the context of ART, aiming for the best possible outcomes for couples and their children.

Semen parameters' mediation effect on the association between advanced paternal age and IVF clinical outcomes: A 10-year retrospective cohort study

OBJECTIVE

To explore the mediation between advanced paternal age and the outcomes of in vitro fertilization (IVF) in a female-adjusted cohort.

METHODS

The study retrospectively included couples undergoing IVF cycles between 2011 and 2020, and whose female partner was free of medical conditions that would significantly worsen clinical outcomes. Data on patient medical conditions, clinical data, and follow-up information were collected. Causal mediation effect analysis adopting both linear/logistic regression and mixed-effects models was carried out to evaluate the effect of paternal age on the outcomes.

RESULTS

21,959 IVF cycles were included in the study. Semen volume, sperm motility and sperm morphology were significantly associated (P value <0.05) with paternal age. A lower fertilization rate was associated with increased paternal age after adjustment for maternal age (adjusted OR = 0.800; 95 % CI, 0.678, 0.943; P value = 0.008). Mediation analysis revealed that A-level sperm rate and progressive rate respectively mediated 37.0 % and 41.0 % of the association between paternal age and fertilization rate.

CONCLUSION

Sperm motility rate, especially A-level sperm rate and rapid progressive rate, mediated the association between advanced paternal age and lower fertilization rate in the cycles.

Effect of paternal age on assisted reproductive outcomes in ICSI donor cycles

BACKGROUND

Despite growing evidence suggesting age-related molecular changes in gametes, the impact of paternal age on clinical outcomes during infertility treatments has not been adequately assessed.

OBJECTIVES

This study aims to assess the correlation of paternal age to clinical pregnancy and live birth rates in egg donation cycles undergoing intracytoplasmic sperm injection.

MATERIALS AND METHODS

This retrospective cohort study includes 4930 fresh oocyte donation cycles from 3995 couples between April 2005 and February 2020 in a private IVF hospital. Clinical pregnancy and live birth rates were the primary outcome measures. The results were also assessed according to the paternal age groups, donor characteristics, semen parameters, fertilization rate, and quality of the transferred embryos.

RESULTS

The age and body mass index of the donors, oocyte maturation, fertilization rates, and the mean number of transferred embryo quality were comparable on day-3 but not on day-5 embryo transfers between paternal age groups (p > 0.05). Paternal age was found to be negatively correlated to the number of oocytes utilized, normal semen parameters, fertilization, clinical pregnancy, and live birth rates (p < 0.05). In day-5 embryo transfer cycles, only the rate of cycles with normal spermatozoa, number of allocated oocytes, and pregnancy were found to be statistically significant.

DISCUSSION AND CONCLUSION

Paternal age may influence reproductive outcomes and should be considered during infertility evaluations in intracytoplasmic sperm injection donor cycles. Further research is needed to confirm these findings.

Fertility in the aging male: a systematic review

The negative effect of advanced female age on fertility and offspring health is well understood. In comparison, much less is known about the implications of male age on fertility, with many studies showing conflicting results. Nevertheless, increasing evidence suggests that advanced paternal age has negative effects on sperm parameters, reproductive success, and offspring health. Herein, we summarize the current body of knowledge on this controversial topic, with the belief that this review will serve as a resource for the clinicians providing fertility counseling to couples with older male partners.

Assessing the impact of semen quality on embryo development in an egg donation model

OBJECTIVE

To investigate if any of the World Health Organization semen parameters and/or male age are associated with embryo development.

DESIGN

Retrospective chart review between January 2008 and May 2015.

SETTING

Academic fertility practice.

PATIENTS

Anonymous egg donors aged ≤30 years.

INTERVENTIONS

Chart review.

MAIN OUTCOME MEASURES

Sperm parameters were evaluated on a continuum and were dichotomized to determine if low values (strict morphology < 4%, concentration < 15 × 106, low motility < 40%) or older age (>50 years) are associated with embryo morphology. Repeated linear regression measures to determine the associations and multivariate testing to determine independent effects for each predictor were performed.

RESULTS

Three hundred eighty-four donors with 574 egg donation cycles were identified, and 205 subjects with 275 cycles were included in the final analysis. The mean donor age was 25.31 ± 2.81 years, with a mean antral follicle count of 28.09 ± 10.5. The mean male age was 43.25 ± 6.65 years. The mean World Health Organization semen parameters at fertilization were 55.8 × 106 ± 44.3 × 106/mL concentration, 44.8% ± 20.2% motility, and 6.9% ± 5.3% strict morphology. Neither male age nor sperm morphology was associated with embryo morphology. A low total motile count was significantly associated with a higher cell number in day-3 embryos and a 1.56-times higher chance of poor day-3 cell symmetry. There was no statistically significant difference in blastocyst formation, clinical pregnancy, or live-birth rates.

CONCLUSIONS

Although statistically significant, the effect of the low total motile count on day-3 cell number and cell symmetry are likely clinically insignificant. Male age, race, or poor sperm morphology were not associated with a poor cycle outcome or impaired embryo development. The use of intracytoplasmic sperm injection likely alleviates the negative effect of diminished semen quality on treatment outcome.

Aging and the Male Reproductive System

This narrative review presents an overview of current knowledge on fertility and reproductive hormone changes in aging men, the factors driving and modulating these changes, their clinical consequences, and the benefits and risks of testosterone (T) therapy. Aging is accompanied by moderate decline of gamete quality and fertility. Population mean levels show a mild total T decline, an SHBG increase, a steeper free T decline, and a moderate LH increase with important contribution of comorbidities (e.g., obesity) to these changes. Sexual symptoms and lower hematocrit are associated with low T and are partly responsive to T therapy. The relationship of serum T with body composition and metabolic health is bidirectional; limited beneficial effects of T therapy on body composition have only marginal effects on metabolic health and physical function. Skeletal changes are associated primarily with estradiol and SHBG. Cognitive decline is not consistently linked to low T and is not improved by T therapy. Although limited evidence links moderate androgen decline with depressive symptoms, T therapy has small beneficial effects on mood, depressive symptoms, and vitality in elderly patients with low T. Suboptimal T (and/or DHT) has been associated with increased risk of stroke, but not of ischemic heart disease, whereas an association with mortality probably reflects that low T is a marker of poor health. Globally, neither severity of clinical consequences attributable to low T nor the nature and magnitude of beneficial treatment effects justify the concept of some broadly applied "T replacement therapy" in older men with low T. Moreover, long-term safety of T therapy is not established.

Prevalence of XXY karyotypes in human blastocysts: multicentre data from 7549 trophectoderm biopsies obtained during preimplantation genetic testing cycles in IVF

STUDY QUESTION

Which is the prevalence of a 47,XXY karyotype in human blastocysts biopsied during preimplantation genetic testing for aneuploidies (PGT-A) cycles?

SUMMARY ANSWER

The prevalence of a 47,XXY karyotype amongst male blastocysts without autosomal aneuploides is ~1%.

WHAT IS KNOWN ALREADY

The prevalence of Klinefelter syndrome is estimated as 0.1-0.2% in male newborns. However, the KS phenotype is extremely variable and there are men with a 47,XXY karyotype and less evident signs, who may go undetected. No risk factor for the 47,XXY karyotype in products of conception has been yet clearly defined, and no data are available regarding the prevalence of this karyotype among human preimplantation embryos.

STUDY DESIGN, SIZE, DURATION

This multicentre cohort study involved 7549 blastocysts obtained during 2826 PGT-A cycles performed between April 2013 and September 2017 at six IVF clinics in Italy.

PARTICIPANTS/MATERIALS, SETTING, METHODS

During 2826 PGT-A cycles, 7549 blastocysts underwent trophectoderm biopsy and quantitative-PCR-based comprehensive chromosomal testing to predict the karyotype of the corresponding embryos. The results were also presented according to ranges of maternal and paternal age at oocyte retrieval as well as sperm factor and blastocyst quality. Univariate and multivariate logistic regression analyses were conducted to investigate the correlation of possible confounding factors with the prevalence of 47,XXY karyotype.

MAIN RESULTS, THE ROLE OF CHANCE

Overall, 62 blastocysts were 47,XXY or had an XXY karyotype associated with autosomal aneuploidies. After exclusion of the latter, the prevalence of a 47,XXY karyotype among male blastocysts without autosomal aneuploidies was 0.9% (n = 17/1794). A significant correlation was only found for maternal age and blastocyst quality (OR: 1.20, 95% CI: 1.01-1.42; P = 0.04 and OR: 1.6, 95% CI: 1.13-2.45; P = 0.01).

LIMITATIONS, REASONS FOR CAUTION

These retrospective data have been produced based on a population of infertile couples undergoing IVF and PGT-A, and the women were mainly of advanced maternal age. Moreover, the qPCR technique is validated only to detect full-chromosome uniform aneuploidies in trophectoderm biopsies.

WIDER IMPLICATIONS OF THE FINDINGS

The 0.9% prevalence of the 47,XXY karyotype among male blastocysts, when compared with the 0.1-0.2% prevalence reported in the prenatal and postnatal periods, suggests four possible scenarios that require further investigations: (i) the latter prevalence is underestimated; (ii) 47,XXY blastocysts result in a lower implantation rate than euploid embryos (estimated to be ≈50%); (iii) 47,XXY blastocysts result in a higher early miscarriage rate than euploid embryos (estimated to be ≈10%); or (iv) infertile patients of advanced maternal age and referred to IVF/PGT-A produce a higher rate of 47,XXY blastocysts.

STUDY FUNDING/COMPETING INTEREST(S)

None.

TRIAL REGISTRATION NUMBER

N/A.

Impact of Paternal Age on Seminal Parameters and Reproductive Outcome of Intracytoplasmatic Sperm Injection in Infertile Italian Women

Background: We conducted a retrospective study on a cohort of couples attending the Department of Andrology and Reproductive Physiopathology at Sandro Pertini Hospital in Rome for Intracytoplasmatic Sperm Injection (ICSI)-assisted reproduction programs. Some of the couples included in the study underwent more than one ICSI cycle. Between January 2015 and April 2017. Objective: To evaluate whether the advancing of the paternal age may have effect on the seminal parameters, thus negatively affecting the embryo formation, development and quality, as well as the pregnancy rate. Materials and Methods: Five hundred and forty three ICSI cycles were performed on 439 couples undergoing Assisted Reproductive Technologies (ART). Patients were subdivided into three male and three female age groups having similar size: Men: ≤38 years (MI), 39-43 years (MII), ≥44 years (MIII). Women: ≤35 years (FI), 36-40 years (FII),≥41 years (FIII). Discussion and Conclusion: Male age groups did not reveal any statistical significant differences in any age-related semen parameters. We also confirmed a statistical significant increase in the pregnancy rate of couples with older partner age difference and younger female. We found that the advanced male age increases the probability of obtaining one or no type A embryo (NA≤1), which was almost doubled in the MIII group in comparison with MI, suggesting a negative effect of male age on the efficacy of the reproductive outcome in terms of a reduced number of type A embryos. Such an effect does not seem related to semen parameters and may deserve further investigations.

Paternal age and assisted reproductive technology: problem solver or trouble maker?

In our society, the number of couples with advanced reproductive age seeking fertility treatment is increasing steadily. While the negative effect of female age on assisted reproductive technology (ART) outcomes is well established, the impact of paternal age needs to be clarified. We reviewed the current literature to determine whether advanced paternal age affects the results of ART and the health of resulting offspring. We found that the published literature is overall supportive of a positive association between advanced paternal age (>40 years) and semen quality deterioration. However, the existing evidence does not corroborate nor discard the influence of advanced paternal age on ART outcomes. Similarly, the effect of paternal age on the health of ART offspring remains equivocal, although data from naturally-conceived children clearly indicates that advanced paternal age increases the frequency of genetic, neurodevelopmental, and psychiatric diseases in the progeny. Noteworthy, the current literature is limited and subjected to bias due to the impact of maternal age as a critical confounder. Health care providers should discuss with concerned couples the available options to counteract the possible negative influence of advanced paternal age on ART outcomes and health of resulting offspring. These include identification and treatment of underlying conditions with potential negative long-term effects on fertility, sperm freezing at a young age, and use of antioxidant supplements for men at risk of excessive oxidative stress. Aged male partner from couples undergoing ART, in particular men of 50 years and older, should consider use of preimplantation genetic testing as a means to detect embryo abnormalities and select euploid embryos for transfer to the uterine cavity.

Paternal age: Negative impact on sperm genome decays and IVF outcomes after 40 years

This study assessed sperm quality declining on relation to paternal age and its impact on in vitro fertilization (IVF) outcomes in order to estimate the APA (Advanced Paternal Age) cutoff. For this, 83 couples undergoing IVF treatment for male factor infertility were enrolled. The women age was ≤39 years, whereas the men were divided in two groups: APA (n = 41; age ≥ 40 years) and young (Y) (n = 42; age < 40 years). Conventional semen parameters (volume, concentration, motility, vitality, and morphology) were analyzed in the collected sperm samples. Furthermore, sperm genome decays (SGD) was assessed by TUNEL assay (DNA fragmentation), aniline blue staining (chromatin decondensation), and fluorescent in situ hybridization (aneuploidy). No significant difference was found concerning the conventional semen parameters between APA and Y groups. Conversely, SGD analysis showed increased DNA fragmentation; chromatin decondensation and sperm aneuploidy rates in the APA group (respectively, 41%, 43%, and 14% vs. 25%, 23%, and 4% in Y group). IVF outcomes also were affected by paternal age as indicated by the rates of cancelled embryo transfers, clinical pregnancy and miscarriage in the two groups APA and Y (29%, 17%, and 60% vs. 10%, 32%, and 42%). Finally, statistical analysis of the results suggests that the age of 40 should be considered as the APA cutoff during ART attempts.

[Effects of father's age on fertility, results of ART and health of children]

Many studies exist on the impact of female age on fertility, success of assisted reproductive technologies and on obstetric, fetal and neonatal adverse outcomes. Late paternity seems commonplace especially in the media… But there are reliable scientific data which confirm decline of fertility related to male age but also an increased risk of genetic diseases for the offspring. The objective of this article is to make a synthesis of the literature on this subject.