Hum. Reprod. Advance Access originally published online on January 23, 2006
Human Reproduction 2006 21(5):1232-1236; doi:10.1093/humrep/dei453
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Results of assisted reproductive technique in men with cystic fibrosis
1 Centre de Ressources et de Compétences pour la Mucoviscidose – Service de Pneumologie, 2 Histologie-Embryologie-Biologie de la Reproduction, 3 Service de Gynécologie-Obstétrique et Médecine de la Reproduction Cochin, 4 Service d’Urologie, 5 Biochimie et Génétique Moléculaire, 6 Génétique Médicale and 7 Service de Gynécologie-Obstétrique et Médecine de la Reproduction Saint Vincent de Paul, Groupe Hospitalier Cochin Saint Vincent de Paul, Assistance Publique Hôpitaux de Paris, Paris, France
8 To whom correspondence should be addressed at: Service de Gynécologie-Obstétrique et Médecine de la Reproduction, Hôpital Saint Vincent de Paul, 82, Avenue Denfert-Rochereau Paris Cedex 14, Paris, France. E-mail: s.epelboin{at}svp.aphp.fr
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Abstract |
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BACKGROUND: Sterility in men with cystic fibrosis (CF) raises the question of the use of assisted reproductive techniques (ART). A multidisciplinary network including adult CF centre and reproductive medicine units was set up to answer requests for ART. METHODS: This retrospective study included 25 men with CF between 1994 and 2004. Clinical status, semen analysis, CF mutations analysis and artificial insemination by donor (AID) or ICSI after surgical retrieval of sperm were monitored. RESULTS: All CF men had azoospermia. Two chose AID first (one delivery); 23 chose ICSI. Sperm were surgically retrieved in 21 cases, and ICSI was performed in 19. Pregnancies occurred in 12 of these 19 couples (63%) (two ectopic pregnancies, two spontaneous abortions, one termination of pregnancy for polymalformed twins and 11 single deliveries in nine couples). Two couples tried AID after ICSI failed; one had twins. Another adopted a child, and two had a spontaneous pregnancy. After a follow-up of 4.1±2.3 years, two patients died, two underwent lung transplantation and 21 remained stable. CONCLUSION: ART can help men with CF to become a father, but their health status and short survival need careful counselling and multidisciplinary medical care.
Key words: assisted reproductive techniques/cystic fibrosis/ethical issues/ICSI
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Introduction |
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The life expectancy and quality of life of cystic fibrosis (CF) patients have greatly improved in recent years. The median length of survival has reached 35 years in the French CF Registry (Institut National des Etudes Démographiques and Vaincre la Mucoviscidose, 2003), and 40% of the patients are adults (Cystic Fibrosis Foundation, 2003).
As many patients now reach adulthood, the issues of fertility and reproductive health are increasing (Sawyer et al., 2005
). Men with CF are almost always infertile because of the congenital absence of the vas deferens, which results in obstructive azoospermia that cannot be surgically corrected (Kaplan et al., 1968). In the last 10 years, assisted reproductive techniques (ART) have improved and may offer these patients the possibility of becoming biological fathers (Lyon and Bilton, 2002).
We have set up a multidisciplinary network to answer requests for medically assisted procreation among CF patients. This network includes a CF pulmonologist specialized in the treatment of adults, a psychologist, a genetic counsellor, a geneticist, a reproductive physician and biologist, a urologist and an obstetrician. We have used a multidisciplinary approach to study the advisability, management and issues of ART in the male patients who have been followed in our adult CF centre for the last 10 years.
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Patients and methods |
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Patients
All the men from our adult CF centre (Cochin Saint Vincent de Paul Hospital, Paris, France) who expressed the desire to become a father and asked for advice from our reproductive network between 1 January 1994 and 31 March 2004 were included in this retrospective study (ART cohort). The clinical characteristics of these CF patients were collected at the time of their first request for medical assistance for procreation and at the beginning of 2004. We compared the characteristics of these men with those of the 130 CF men followed at our CF centre during 2003.
The following parameters were recorded: age at diagnosis, age at the time of first request for assisted reproduction, BMI (weight/height2), results of pulmonary function tests [forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) expressed as the percentage of the predicted value], chronic bronchial colonization with Pseudomonas aeruginosa and pancreatic status. Chronic treatments with intravenous antibiotics and home oxygen were also registered.
Urologic evaluation
All the patients were examined by the urologist. Clinical examination evaluated testis volume, epididymal corpus and cauda and the presence or lack of vas deferens. An ultrasound examination aimed to confirm the absence of vas deferens. At least one semen sample was analysed to evaluate semen volume, pH, sperm count and seminal biomarkers.
Partner fertility evaluation
A classical check-up was performed, including investigation of history, general and gynaecological examination, evaluation of hormonal status on day 3 of the cycle, tubal patency, uterus size and form and implantation ability.
Cystic fibrosis transmembrane conductance regulator genotyping and genetic counselling
CF genetic analysis was performed with a commercially available oligonucleotide ligation assay kit (Cystic Fibrosis Assay, Applied Biosystems, Foster City, CA, USA), which seeks 31 mutations. For totally or partially uncharacterized samples, all 27 exons and flanking regions of the cystic fibrosis transmembrane conductance regulator (CFTR) gene were screened for mutations and polymorphisms by denaturing gradient gel electrophoresis using PCR-amplified genomic DNA (Bienvenu et al., 1995). The CF mutations were classified as severe or mild according to the primary mechanism of defective CFTR function (Zielenski and Tsui, 1995). CFTR genotypes were defined as severe if the patient had two severe mutations, as mild if he had at least one mild mutation and as indeterminate if only one severe mutation or no mutations were identified.
Genetic counselling was offered to all the couples who were followed by our multidisciplinary network. The genotype of the female partner was determined before starting the assisted reproduction programme. When none of the 31 most frequent CF mutations was detected in the female partner, the risk of CF in the offspring was estimated to be 1 in 500 and no systematic amniocentesis was thus performed in case of pregnancy.
Couple
A minimal length of 2 years of conjugal life was required, as expressed in the French bioethics law. Information about techniques and modalities of pregnancy follow-up was completed during the preconceptional outpatient visits.
ICSI
Women underwent ovulation induction with agonist or antagonist protocols. Hormonal and ultrasound ovarian surveys were without specificity. Low-dose protocols were most frequently used because of the very young age of CF men’s partners, who underwent ovulation induction without any ovarian pathology, and there was a major risk of ovarian hyperstimulation (OHS) and multiple pregnancy. Oocyte retrieval was performed under vaginal ultrasound guidance. Spermatozoa were surgically retrieved by micro-epididymal sperm aspiration (MESA) or testicular biopsy. They were freshly used at the day of oocyte retrieval or partially preserved or cryopreserved for delayed use, allowing retrieval of sperm and oocytes at different times. Assisted fertilization by ICSI was performed in the hours following oocyte collection. Fertilization was assessed at 18 h, and embryos were transferred to the uterus 2 or 3 days following ICSI. Results are expressed as the fertilization rate per cycle, defined as the ratio of the number of zygotes to the mature retrieved oocytes, and the pregnancy rate per cycle, defined as the ratio of the number of pregnancies after fresh or frozen–thawed embryo transfer following the same cycle to the number of ICSI cycles.
Pregnancies and children survey
Most pregnancies were followed in our obstetric unit. All events concerning maternal or fetal welfare during pregnancy or birth, as well as post-natal considerations, were recorded.
All children had a specific paediatric examination before discharge from hospital. Children’s health and family well-being were later documented at the time of the father’s visits to our adult CF centre.
Statistical analysis
Results are reported as mean ± SD. Frequencies were compared by using the chi-square method. Comparisons among groups were performed with parametric and non-parametric tests when appropriate. Statistical significance was defined by P < 0.05. Analyses were performed using a statistical software.
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Results |
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Proportion of male CF patients seeking fertility treatment
During the 10-year study period, 25 CF men requested advice concerning medically assisted procreation and were seen by at least two physicians belonging to our network. Twenty-three of these men were alive at the end of the study, representing 17% of the 135 CF male patients attending our CF centre in 2004.
Clinical characteristics of the ART cohort
The clinical characteristics of the 25 male patients in the ART cohort are summarized in Table I. Their median age was 29 years at the time they first sought advice for infertility. The main clinical characteristics of their CF were not different from those of our total CF male population (age at diagnosis, pancreatic status, P. aeruginosa chronic bronchial colonization, pulmonary function, nutritional status, number of i.v. antibiotic courses or oxygen treatment). Four of them were diagnosed with CF late during fertility investigations. Two patients had undergone lung transplantation 4 and 6 years before assisted reproduction; sperm retrieval had been performed before transplant in the first patient, and the second one required artificial insemination by donor (AID).
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The mean age of the partners of the CF men was 26.9 ± 3.4 years (20–36); four were aged less than 25 years. None presented a specific infertility factor. No side effects of hormonal treatment or oocyte retrieval were observed in these women. None of the 31 tested CFTR mutations was detected in the female partners.
Genotype
Among our 25 patients, 12 were homozygous for F508del, seven were heterozygous for F508del and six had no F508del mutation. This corresponded to 17 severe genotypes and eight mild genotypes, which is not statistically different from our total CF male population (Table I).
Urologic evaluation
All 25 CF men were azoospermic. Clinical examination showed a normal testis volume, no epididymal cauda and no vas deferens in all cases. No relation was found between sperm characteristics and men CFTR genotype. The mean volume of the ejaculate was 0.76 ± 0.11 ml (0.15–2.5) and pH 6.75 ± 0.35 (6.2–7.4). Hormonal values were within expected ranges. Mean seminal vesicle and epididymal markers were very low and biochemical markers of prostate normal.
ART
Among the 25 men who asked for assisted reproduction, two chose AID as a first option. Only one of these couples gave birth to a live child.
The other 23 men asked for ICSI. Spermatozoa were retrieved from 21 patients (by MESA in 19 cases and by testicular biopsy in two cases), and sperm retrieval is planned in one patient. Anaesthesiologists refused the procedure, even with peridural analgesia, for a patient with severe respiratory insufficiency, who was on a waiting list for lung transplantation.
ICSI has been performed in 19 couples and is planned in three other couples. Fertilization rate was 61%. A mean number of 2.1 and 1.9 embryos were transferred after fresh and frozen transfers, respectively. Sixteen clinical pregnancies (40% per cycle) occurred as a result of ICSI in 12 of the 19 couples (63%) (Table II). Four pregnancies were not evolutive and led to two early miscarriages (one concerning twins) and two ectopic pregnancies. One therapeutic abortion was performed for an early ultrasonographic diagnosis of major malformation in dizygotic twins (one major severe urogenital malformation and one severe thoracic tumour). Eleven pregnancies led to single-term deliveries (11 live newborns). There were four girls and seven boys. In seven couples, no pregnancy was obtained after ICSI.
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In total, nine of the 19 couples (47%) have had a child after ICSI (one child in seven couples and two children in two couples). Among the 10 couples who had no children after ICSI, two couples requested AID. This has failed in one couple and resulted in the birth of twins in the other couple. One couple adopted a child after four unsuccessful ICSI attempts. The wives of two CF men became spontaneously pregnant, respectively, 3 and 4 weeks after ICSI had failed, resulting in the birth of one girl and twins (boy and girl), all of whom are healthy. It was not possible to control the CFTR genotype of the children.
Moreover, 14 of 25 couples (56%) had 18 children (Table III). nine couples after ICSI (two successive children in two cases), two couples after AID, two after spontaneous pregnancy and one through adoption.
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Follow-up
After a mean follow-up of 4.1 ± 2.3 years (range, 1–9), two of the 25 patients have died. One patient, who had refused lung transplantation, died 5 years after the birth of his daughter by ICSI. The other patient died of renal insufficiency and bronchiolitis obliterans 10 years after lung transplantation and 4 years after the beginning of unsuccessful AID.
The other 23 patients have a stable clinical status and respiratory function. At the end of the study, their mean age was 33.4 ± 5.6 years. Their mean FEV1 was 45.5 ± 23.4% predicted, mean FVC 64.3 ± 23.1% predicted and mean BMI 19.7 ± 2.4 kg/m2.
Two patients underwent lung transplantation after the beginning of the study, with a follow-up of 7 years and 6 months after transplantation. One of them, whose wife had a termination of pregnancy before transplantation for polymalformed twins, had healthy twins by AID 18 months after the lung transplantation. The other one could not undergo sperm retrieval because of too-severe respiratory insufficiency before lung transplantation and has not yet requested ART again.
At the time of this study, one child was 9, one was 6, one was 5, and 8 were 1–4 years old. Paediatric follow-up has revealed no concern in 10 of the 11 children born after ICSI. Only one live-born child conceived by ICSI (non-transplanted father) displayed a congenital malformation: meningocele of cerebellum. This 19-month-old boy had common paediatric follow-up, neither hospitalization nor surgery and presents a normal neurological development.
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Discussion |
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TopAbstractIntroductionPatients and methodsResultsDiscussionReferences |
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Owing to the increasing number of CF patients reaching adulthood with a better quality of life, more adults with CF wish to have children. This is why we have set up a multidisciplinary reproduction network in our adult CF centre. Here, we report our results of this reproduction network for 25 males with CF over the last 10 years and the outcome of fertility treatments. It has been reported that disease severity was not related to a desire for having children (Sawyer et al., 2005
). Our ART cohort was similar to our CF cohort in terms of genotype and phenotype. Boyd et al. (2004) also reported that 18 men with CF whose partners were pregnant were similar to 1329 men whose partners were not pregnant. Four of our patients have undergone lung transplantation (two before and two after ART). Two patients died (one after lung transplantation). In an Australian study, six of the 12 men with CF treated with ART had undergone lung transplantation (Bye et al., 2003).
Almost all males with CF are azoospermic because of congenital bilateral absence of the vas deferens (CBAVD) (Kaplan et al., 1968). This is even the case for patients with a mild phenotype, meaning that azoospermia has been suggested as a major criterion for the diagnosis of CF (Stern et al., 1982). It seems that CBAVD develops with time because of inspissation of secretions and secondary atresia. In CF fetuses, the vas deferens appears similar to that of normal controls but with secretions filling the mid vas (Gaillard et al., 1997). Ductal genital abnormalities are less frequent in male CF children than in adults (Blau et al., 2002). All 25 patients who were referred to our reproduction network had azoospermia.
Until the development of IVF and particularly of ICSI, which allowed them to be the biological father of their children (Silber et al., 1990; Oates et al., 1992; Palermo et al., 1992), AID or adoption was the only option for male CF patients who wanted to be a father.
ICSI was chosen as the first option for sterility treatment by 23 of these patients and had been performed in 19 patients at the end of the study. The remaining two patients chose AID as a first option.
Among the 19 couples treated with ICSI, the pregnancy rate was 40% per ICSI cycle, 12 of 19 couples (63%) had a clinical pregnancy and nine of 19 (47%) had a live-born child. These results are good in comparison with those of ICSI in men with CBAVD, where the pregnancy rate varies from 20 to 53% (Silber et al., 1995; Son et al., 1996; Mansour et al., 1997; Yamamoto et al., 1997; Viville et al., 2000).
The pregnancy rate in this study is in agreement with the results of McCallum et al. (2000), where the pregnancy rate in partners of CF males was 62.5% after ICSI; five of eight couples achieved pregnancy, resulting in one miscarriage and the births of seven children (three sets of twins and one singleton). The rate of term live births among partners of males with CF in the UK (Boyd et al., 2004) is also very similar (67%). Bye et al. (2003) reported 11 pregnancies in 12 couples after ICSI; two couples had twins and two couples achieved pregnancies on two occasions. Among 18 English males with CF referred for fertility treatment, only 10 chose ICSI and six women had children, including three sets of twins (Elkin et al., 2004). This excellent pregnancy rate in partners of men with CF is partly due to the young age of the female partners. Furthermore, this can lead to the practice of single-embryo transfer to avoid twin pregnancy in these families.
AID and adoption remain options in cases of failed ICSI. CF parental disease is not an absolute obstacle to achieve adoption in France, but adoption depends on acute medical and social investigations and is not available in many cases. Among our ICSI failures, one couple adopted and one pregnancy was obtained after AID.
Two couples obtained spontaneous pregnancies after ICSI had failed. In these two cases, men had neither larger ejaculate volume nor specific seminal vesicle or epididymal markers. Rare cases of fertile males or of spermatozoa in semen have been described in CF (Barreto et al., 1991; Stern et al., 1995; Hubert et al., 2004), but for ethical reasons no paternity test was performed in our two cases. In a French retrospective study (Duguépéroux et al., 2004), 12 CF centres reported 48 men who fathered 69 children: 47 births occurred after medically assisted procreation (24 after AID and 23 after ICSI), 18 births (26%) were natural conceptions and four were adoptions. Seventeen of 94 men (18%) who attended a CF clinic in Melbourne had 27 children (Sawyer et al., 2005). Seven of these 17 men were the biological fathers, six through assisted reproduction and one naturally. Of the remaining 10, nine had used AID and one had stepchildren.
Malformation rate includes therapeutic abortion following antenatal diagnosis and malformations diagnosed at birth and in post-natal life. Of 16 clinical pregnancies after ICSI, 12 were evolutive, among which one was terminated at 14 weeks of amenorrhea for two malformed twins, and one of 11 single deliveries led to the birth of a boy with meningocele. Thus, the major malformation rate calculated for evolutive pregnancies ongoing over 13 weeks of amenorrhea (SA) was 23% (3 of 13). In our Saint Vincent de Paul ART centre, between 1999 and 2003, the rate of major malformations (including therapeutic abortion following antenatal diagnosis as well as malformations diagnosed at birth and in post-natal life) was 3 of 86 second trimester evolutive pregnancies (3.5%) after all ICSI (except those in CF men). These diagnoses were based on a widely consensual network of registers, European Concerted Action on Congenital Anomalies and Twins (EUROCAT). Similar rates were observed in the French multicentre register French IVF national register (FIVNAT) and in many referent published cohorts. The small size of the CF male cohort, as well as the diversity of the malformations, does not allow any specific comment but means we should pay attention to all issues of future pregnancies.
Moreover, ethical issues have to be discussed (Lyon and Bilton, 2002). Before becoming a father, CF men must be informed about their own health and long-term issues such as the likelihood of premature death. This information should be clearly shared with their partner. The prospect of lung transplantation should also be discussed, with suitable information on the complications and the post-transplantation survival rates. Physicians responsible for the treatment of adult CF patients do not have the right to prevent an adult from becoming a parent but are responsible for discussing these issues.
In conclusion, most patients with CF now become adults with a better quality of life and many of them want to have children. Developments in the field of ART provide CF men and women (Epelboin et al., 2001) more opportunities to become parents. The development of a multidisciplinary network of physicians seems a good way to assist CF patients in their quest for becoming parents. ICSI is usually the first option chosen by men who want to be a father, but other possibilities are available such as AID and adoption.
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References |
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Submitted on July 15, 2005; resubmitted on November 8, 2005; accepted on November 17, 2005.
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