Sperm retrieval and intracytoplasmic sperm injection outcomes in men with cystic fibrosis disease versus congenital bilateral absence of the vas deferens

Comparative genetic analysis of blood and semen samples in sperm donors from Hunan, China

OBJECTIVES

At present, most genetic tests or carrier screening are performed with blood samples, and the known carrier rate of disease-causing variants is also derived from blood. For semen donors, what is really passed on to offspring is the pathogenic variant in their sperm. This study aimed to determine whether pathogenic variants identified in the sperm of young semen donors are also present in their blood, and whether matching results for blood are consistent with results for sperm.

METHODS

We included 40 paired sperm and blood samples from 40 qualified semen donors at the Hunan Province Human Sperm Bank of China. All samples underwent exome sequencing (ES) analysis, and the pathogenicity was assessed according to the American College of Medical Genetics (ACMG) guidelines. Scoring for sperm donation matching, which was based on gene scoring and variant scoring, was also used to assess the consistency of sperm and blood genetic test results.

RESULTS

A total of 108 pathogenic (P)/likely pathogenic (LP) variants in 82 genes were identified. The highest carrier had 7 variants, and there was also one donor did not carry any P/LP variant. On average, each donor carried 2.7 P/LP variants. Among all the P/LP variants, missense mutation was the dominant type and most of them were located in exonic regions. Chromosome 1 harboured the largest number of variants and no pathogenic copy number variants (CNV) was identified in semen donors. The P/LP variant of all the 40 semen donors was consistent by comparing sperm and blood. Except for one case that was slightly different, the rest simulated matching results for blood were all consistent with results for sperm.

CONCLUSIONS

It is reasonable to choose either blood or sperm for genetic screening in semen donors.

Success Rates of Assisted Reproduction for Men With Cystic Fibrosis

BACKGROUND

The vast majority of men with CF (mwCF) are infertile. Improvements in assisted reproductive technology (ART) have made it possible for these patients to become biological fathers.

METHODS

Data were examined for all male CF patients attending a large adult CF center over a 23-year period. Azoospermia was confirmed via laboratory analysis of semen and was defined as complete absence of sperm in the ejaculate. Outcome of surgical sperm retrieval (SSR) procedure, post SSR complications, success rate of intracytoplasmic sperm injection (ICSI) and embryo transfer and subsequent live births were evaluated.

RESULTS

Seventy-one mwCF with proven azoospermia were referred to fertility services over the study period. Mean (SD) percentage predicted forced expiratory volume in 1 second (ppFEV1) 67.86 ( ± 25.3), body mass index (BMI) 24.3 ( ± 3.7) kg/m2. Seventy (98.5%) of these men underwent and had successful SSR. 67/71 (94%) couples proceeded to have ICSI post SSR. 11 couples had failed egg fertilisation, implantation, or early miscarriage. 56/67 couples (84%) went on to have live births. To date 10/71 (14%) mwCF referred for fertility treatment have died. Mean ppFEV1 and BMI of mwCF who survived was higher than those who died; FEV1 72.8% ( ± 23.4) versus 38% ( ± 12.0) (p < 0.001), BMI 25.0 ( ± 3.5) kg/m2 versus 20.3 ( ± 2.2) kg/mg2 (p < 0.001).

CONCLUSION

This is the largest study to investigate success rate of fertility treatment in mwCF and demonstrates that fertility treatment is successful in greater than 75% of patients referred. Clinical status and prognosis remain important factors when considering referral to fertility services.

Genetic diagnosis and outcomes of intracytoplasmic sperm injection in South Chinese patients with congenital bilateral aplasia of the vas deferens

BACKGROUND

Obstructive azoospermia commonly is caused by CBAVD(Congenital Bilateral Aplasia of the Vas Deferens), mainly due to the cystic fibrosis transmembrane conductance regulator (CFTR) and adhesion G protein-coupled receptor G2(ADGRG2) mutations. The genetic landscape for Chinese CBAVD patients is unclear, leading to debates over genetic screening, counseling, and assisted reproduction strategies. This study investigates the prevalence of CFTR and ADGRG2 mutations in a southern Chinese cohort of CBAVD patients and evaluates the impact of CFTR mutations on intracytoplasmic sperm injection (ICSI) outcomes.

RESULTS

CFTR mutations were identified in 71.4% (30/42) of CBAVD patients, with a total of 36 CFTR mutation sites across 13 types identified, including two novel mutations. A novel ADGRG2 mutation was also detected. Betweenthe CFTR mutation-CBAVD group and the non-CBAVD OA group, a significant difference was observed only in the 2 Pronuclei(2PN) rate (79.5% vs 86.2%, P = 0.0065), while fertilization rates, pregnancy rates, miscarriage rates, and live birth rates showed no significant differences. Between the CFTR mutation-CBAVD group and the CBAVD group without CFTR mutation, there were no significant differences in fertilization rates, 2PN rates, pregnancy rates, miscarriage rates, or live birth rates.

CONCLUSION

Chinese CBAVD patients primarily exhibit mutations in the CFTR and ADGRG2 genes. Therefore, targeted gene testing for CFTR and ADGRG2 is more suitable compared to WES for CBAVD patients. Considering that the genetic factors of approximately 30% of CBAVD patients remain unknown, it is recommended to perform massive parallel sequencing for patients who test negative for CFTR and ADGRG2 gene screening. Despite these genetic factors, ICSI outcomes were not adversely affected, except for the 2PN rate. However, genetic counseling remains crucial for Chinese CBAVD patients before undergoing assisted reproduction.

Pregnancy and fertility in people with cystic fibrosis following lung transplantation

PURPOSE OF REVIEW

The purpose of this review is to summarize available data on fertility, fertility preservation, pregnancy and parenthood following lung transplantation for people with cystic fibrosis (pwCF).

RECENT FINDINGS

In the era of cystic fibrosis transmembrane conductance regulator (CFTR) modulator use, oral therapies that positively impact fundamental CFTR protein abnormalities, the number of pregnancies has increased dramatically with a concomitant decrease in lung transplantation. Nonetheless, some pwCF still require lung transplantation as a life-saving measure, and a fraction of those individuals desires parenthood. Cystic fibrosis (CF) providers infrequently discuss fertility preservation with pwCF, and pwCF feel uneducated about their fertility options posttransplant. However, because the immunosuppression required to successfully maintain lung allografts may impact future fertility, pwCF should receive genetic and reproductive counseling prior to lung transplantation. While pregnancies posttransplantation are high-risk, selected females with CF may be able to pursue this path to parenthood.

SUMMARY

Although there is a paucity of data specific to pwCF who have undergone lung transplantation, recently developed general guidelines should inform discussions regarding fertility, pregnancy and parenthood in pwCF who desire parenthood following lung transplantation for optimal shared decision-making.

Prioritizing sexual and reproductive health research and care for people with cystic fibrosis: A 2023 workshop report from the Cystic Fibrosis Foundation Sexual Health, Reproduction, and Gender (SHARING) Research Working Group

BACKGROUND

To address sexual and reproductive health (SRH) concerns among people with cystic fibrosis(PwCF), the CF Foundation created the Sexual Health, Reproduction, and Gender Research (SHARING) Working Group. This report summarizes CF community SRH research priorities and workshop discussions/future study planning.

METHODS

Pre-workshop, we distributed a community prioritization survey on CF SRH research/care. During the workshop, we used results and reviewed existing research to establish research priorities and design studies to address identified knowledge gaps.

RESULTS

A total of 303 respondents (85 % PwCF, 15 % caregivers) completed the survey. Highly-rated SRH topics were: 1) effects of CF modulator therapy on sex hormones; 2) effects of sex hormones on CF; 3) fertility; 4) pregnancy; and 5) SRH/mental health. Twenty-four workshop participants established the need for further research on sex hormones and CF, optimizing SRH care provision, and fertility/ART.

CONCLUSION

SRH is an important and emerging area in CF and thoughtful consideration of community perspectives can ensure that future research is relevant and responsive.

Optimizing sexual reproductive health of men and women with cystic fibrosis: A systematic review

This systematic review summarizes the impact of cystic fibrosis (CF) on sexual and reproductive health (SRH) in males and females, covering pubertal development, hormonal function, family planning, and fertility. Included articles featured historical CF diagnostic criteria, preclinical or clinical data (retrospective cohorts or open label trials), while excluded articles lacked full text availability, explicit methodology, or comparisons between CF and non-CF patients. Genotype differences in CFTR mutations influenced symptom severity. Males with CF experienced delayed puberty, hypogonadism, infertility from obstructive azoospermia, and semen parameter issues. Female CF patients showed decreased fertility, possibly linked to disrupted ionic balance and ovarian cystic disease. Assistive reproductive technologies addressed fertility issues, but success varied based on disease severity and genotype. CFTR modulators aided pulmonary function and sexual health but require further assessment for fertility benefits.

A provider survey assessing fetal impact of CFTR modulator use in males with CF during assisted and unassisted reproduction and partner pregnancy

BACKGROUND

Most males with cystic fibrosis (mwCF) are infertile but with CF transmembrane conductance regulator (CFTR) modulator-conferred benefits, more are utilizing assisted reproductive technologies (ART). Administration of normal human doses of modulators in animal reproductive models caused no genotoxicity; no human data exists. Potential health decline following modulator discontinuation makes the decision to withhold therapy during reproduction challenging.

METHODS

From August-October 2021, international CF clinicians completed an anonymous questionnaire regarding mwCF who used modulators during reproduction.

RESULTS

We received 42 surveys for mwCF with partner pregnancies. Forty of 42 mwCF utilized ART; 35 continued modulators during sperm retrieval and 40/42 during partner pregnancy. One of four males who discontinued modulators experienced clinical deterioration. First trimester miscarriages occurred in 11.9 % of partner pregnancies. No congenital anomalies were reported.

CONCLUSIONS

Use of CFTR modulators during reproduction and partner pregnancy in mwCF did not result in a higher-than-expected miscarriage rate nor congenital anomalies.

An overview of CFTR mutation profiles and assisted reproductive technology outcomes in Chinese patients with congenital obstructive azoospermia

PURPOSE

The cystic fibrosis transmembrane conductance regulator (CFTR) is the most common causative gene attributed to congenital obstructive azoospermia (OA). The aim of this study was to conduct an epidemiological survey of congenital OA patients, to screen for CFTR mutations, and to follow their pregnancy outcomes in assisted reproductive technology (ART).

METHODS

This cohort study enrolled congenital OA patients undergoing ART and whole-exome sequencing from January 2018 to September 2023. Semen parameters, sex hormones, and seminal plasma biochemistry were evaluated. CFTR mutations identified in OA patients were analyzed. In addition, the laboratory outcomes, clinical outcomes, and neonatal outcomes were compared between OA patients carrying two CFTR mutations and the others after surgical sperm extraction-intracytoplasmic sperm injection (ICSI) treatment.

RESULTS

A total of 76 patients with congenital OA were enrolled. CFTR mutations were identified in 35 (46.1%) congenital OA patients. A total of 60 CFTR mutation sites of 27 types were identified, and 10 of them were novel. The average frequency was 1.71 (60/35) per person. The most common mutation was c.1210-11T > G (25%, 15/60). After ICSI treatment, there were no statistically significant differences in laboratory outcomes, clinical outcomes, and neonatal outcomes between OA patients carrying two CFTR mutations (n = 25) and other OA patients (n = 51).

CONCLUSION

Apart from the IVS9-5T mutation, the genetic mutation pattern of CFTR in Chinese OA patients is heterogeneous, which is significantly different from that of Caucasians. Although carrying two CFTR mutations or not had no effect on the pregnancy outcomes in OA patients after ICSI, genetic counseling is still recommended for such patients.

The modern landscape of fertility, pregnancy, and parenthood in people with cystic fibrosis

PURPOSE OF REVIEW

With improved long-term survival and the expanding availability of cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapies that treat the underlying genetic defect in cystic fibrosis, more people are interested in parenthood. Cystic fibrosis care centers and people with cystic fibrosis need more information to guide decisions related to parenting.

RECENT FINDINGS

Here we present currently available data on fertility, pregnancy, and parenthood in the modern era of cystic fibrosis care. Fertility may be improving in female individuals with cystic fibrosis with the use of CFTR modulator therapies, and there is an associated increase in annual pregnancies. Infertility in male individuals with cystic fibrosis remains approximately 97-98% and is unchanged with CFTR modulators in those already born with cystic fibrosis. As more female individuals with cystic fibrosis experience pregnancy, questions remain about the impact of pregnancy on their health and that of their child. Fortunately, there are multiple routes to becoming a parent; however, more work is needed to understand the impact of pregnancy and parenthood in the context of CF as some previous data suggests potential challenges to the health of parents with cystic fibrosis.

SUMMARY

We encourage cystic fibrosis care teams to have knowledge and resources available to support the reproductive goals of all individuals with cystic fibrosis.

Sexual and Reproductive Health Among Men With Cystic Fibrosis

Cystic fibrosis (CF) is a genetic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) protein. Due to the distribution of the CFTR protein, CF presents with a heterogeneous phenotype. Men with CF may present with infertility due to congenital abnormalities of the vas deferens. In addition, they may experience testosterone deficiency. Today, they can father biological children with assisted reproductive technologies. We reviewed the current literature on the pathophysiology of these conditions, describe interventions that allow men with CF to conceive biological children, and provide recommendations for management of CF patients with reproductive health concerns.

Reproductive Counseling and Care in Cystic Fibrosis: A Multidisciplinary Approach for a New Therapeutic Era

With the advent of highly effective modulator therapies, many people with cystic fibrosis (CF) are living longer, healthier lives. Pregnancy rates for women with CF more than doubled between 2019 and 2021, reflecting increases in both planned and unplanned pregnancies. For men with CF, CF-associated infertility can be mitigated with assistive reproductive technology, yet patient knowledge of these challenges and options is variable. Preconception and prenatal counseling for individuals with CF and for parents of children with CF who wish to expand their families requires nuanced discussions to promote informed reproductive decisions, drawing from a combination of standard practice recommendations and CF-specific assessments. This review article synthesizes the current literature and practice recommendations regarding reproductive counseling and care in CF, outlining the role of genetic counseling, carrier screening, teratogen counseling, in vitro fertilization and pre-implantation genetic diagnosis, and careful assessment and management of cystic fibrosis-related diabetes when present. Via a multidisciplinary, patient-centered approach, clinicians can support adults with CF and parents of children with CF as they make informed reproductive decisions and embark on family planning.

Correlation between CFTR variants and outcomes of ART in patients with CAVD in Central China

Biallelic variants in Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) are the main pathogenic factor of congenital absence of the vas deferens (CAVD), including congenital bilateral absence of the vas deferens (CBAVD) and congenital unilateral absence of the vas deferens (CUAVD). However, there are few reports about the correlation between CFTR variant and outcomes of assisted reproductive technology (ART) in CAVD patients of China. In this study, 104 patients with CAVD were recruited in Central China, and provided gene detection by the whole-exome sequencing, among them 69% (72/104) carried at least one variant in CFTR and one carried adhesion G protein-coupled receptor G2 (ADGRG2) variant. A total of 81 CAVD patients were treated with ART, of which 21 and 60 carried none or at least one variant in CFTR, respectively. The fertilization rate, cleavage rate, effective embryo rate, implantation rate, clinical pregnancy rate and live birth rate per fresh embryo transfer were compared between patients with and without CFTR variants. It was found that the ART outcomes had no significant difference whether the patients carried the CFTR variant or not. In addition, all of the offspring were healthy after follow-up. In conclusion, rare CFTR variants may play a major role in patients with CAVD in Central China, which were greatly different from other descent. There was no significant difference in ART outcomes in CAVD patients with or without CFTR variants. The limitations of this study were that there was no statistical analysis of the sperm quality through TESA and conclusions were relatively limited due to the small sample size of the study.

Heterogeneous spectrum of CFTR gene mutations in Chinese patients with CAVD and the dilemma of genetic blocking strategy

In brief

The genetic heterogeneity of CFTR gene mutations in Chinese patients with congenital absence of the vas deferens (CAVD) differs from the hotspot mutation pattern in Caucasians. This paper reviews and suggests a more suitable screening strategy for the Chinese considering the dilemma of CFTR genetic blocking.

Abstract

Congenital absence of the vas deferens (CAVD) is a major cause of obstructive azoospermia and male infertility, with CFTR gene mutation as the main pathogenesis. Other genes such as ADGRG2, SLC9A3, and PANK2 have been discovered and proven to be associated with CAVD in recent studies. Multiple CFTR hotspot mutations have been found in Caucasians in several foreign countries, and relevant genetic counseling and preimplantation genetic diagnosis (PGD) have been conducted for decades. However, when we examined research on Chinese CAVD, we discovered that CFTR mutations show heterogeneity in the Chinese Han population, and there is currently no well-established screening strategy. Therefore, we have reviewed the literature, combining domestic and international research as well as our own, aiming to review research progress on the CFTR gene in China and discuss the appropriate scope for CFTR gene detection, the detection efficiency of other CAVD-related genes, and the screening strategy applicable to the Chinese Han population. This study provides more valuable information for genetic counseling and a theoretical basis for PGD and treatment for couples with CAVD when seeking reproductive assistance.

Genetic analysis and intracytoplasmic sperm injection outcomes of Chinese patients with congenital bilateral absence of vas deferens

PURPOSE

Congenital bilateral absence of the vas deferens (CBAVD) is a major cause of obstructive azoospermia and male factor infertility. CBAVD is mainly caused by mutations in the genes encoding CFTR (cystic fibrosis transmembrane conductance regulator) and ADGRG2 (adhesion G protein-coupled receptor G2). This study aimed to describe CFTR and ADGRG2 variations in 46 Chinese CBAVD patients and evaluated sperm retrieval and assisted reproductive technology outcomes.

METHODS

The CFTR and ADGRG2 genes were sequenced and analyzed by whole-exome sequencing (WES), and variations were identified by Sanger sequencing. Bioinformatic analysis was performed. We retrospectively reviewed the outcomes of patients undergoing sperm retrieval surgery and intracytoplasmic sperm injection (ICSI).

RESULTS

In total, 35 of 46 (76.09%) patients carried at least one variation in CFTR, but no copy number variants or ADGRG2 variations were found. In addition to the IVS9-5 T allele, there were 27 CFTR variations, of which 4 variations were novel and predicted to be damaging by bioinformatics. Spermatozoa were successfully retrachieved in 46 patients, and 39 of the patients had their own offspring through ICSI.

CONCLUSION

There are no obvious hotspot CFTR mutations in Chinese CBAVD patients besides the IVS9-5 T allele. Therefore, WES might be the best detection method, and genetic counseling should be different from that provided to Caucasian populations. After proper counseling, all patients can undergo sperm retrieval from their epididymis or testis, and most of them can have their own children through ICSI.

"Fertility and Pregnancy in Cystic fibrosis"

People with Cystic fibrosis (pwCF) have experienced increased survival and wellbeing in recent decades, such that more than half of those living with CF are adults. Consequently, sexual and reproductive health is increasingly important for pwCF as many are considering parenthood. Most men and some women with CF (wwCF) will have reduced fertility, which in both sexes is multifactorial. However, unplanned pregnancies in women are not rare, and contraception and its interaction with CF complications need to be addressed by the CF team. Reduced fertility may be overcome in most pwCF through use of assisted reproductive technologies; however, the risk of having offspring with CF must be considered. Most wwCF will have normal pregnancies, but premature birth is common especially in the setting of reduced lung function and CF related diabetes (CFRD); optimization of treatment is recommended during pregnancy planning. Parenting imposes an increased burden on pwCF, with the challenges of caring for the newborn, postpartum physiologic changes and maintaining CF treatments. Most drugs used to treat CF are considered safe in pregnancy and lactation, but exceptions need to be acknowledged, including the limited data regarding safety of CF transmembrane conductance regulator (CFTR) modulators during conception, pregnancy, and lactation. As most pwCF are eligible for highly effective CFTR modulators, fertility, contraception, and pregnancy in people with CF is changing. Prospective studies regarding these issues in people treated with CFTR modulators are paramount to provide evidence-based guidance for management in the current era of CF care.

Differential Diagnosis of Azoospermia in Men with Infertility

The differential diagnosis between obstructive and nonobstructive azoospermia is the first step in the clinical management of azoospermic patients with infertility. It includes a detailed medical history and physical examination, semen analysis, hormonal assessment, genetic tests, and imaging studies. A testicular biopsy is reserved for the cases of doubt, mainly in patients whose history, physical examination, and endocrine analysis are inconclusive. The latter should be combined with sperm extraction for possible sperm cryopreservation. We present a detailed analysis on how to make the azoospermia differential diagnosis and discuss three clinical cases where the differential diagnosis was challenging. A coordinated effort involving reproductive urologists/andrologists, geneticists, pathologists, and embryologists will offer the best diagnostic path for men with azoospermia.