INTRODUCTION:

Infertility is a term used to define as a disease of the human reproductive system where the body fails to achieve pregnancy after sexual intercourse. World health organization (WHO) has reported infertility as a chronic health disorder which affects both men and women all across the world.¹

Infertility is a condition which do not induce any pain, morbidity, or physical restrictions. But many studies had revealed that infertility can cause emotional and behavioural changes. The psychological and social impact of the problems caused by the infertility not only affect the patients but also their partners are equally affected and this is a cause for many distress for health professionals.

The incidence of infertility has been increased over the past decades and many healthcare professionals admit that the incidence of infertility will increase in the coming years. Due to the increased prevalence and distressing impact infertility has been included as a spot lit programme in events for reproductive and children’s health in India.^2,3

Various factors affect fertility such as the age of couple, frequency of coitus, sexual exposure. Among the normal couples married at the age of 23-25, 25% of them have a chance to get pregnant after indulging in unprotected sexual intercourse and vast majority of the coupes get pregnant within the 1^st year. In a country like India only less than 5% of the people delay their conception to two years and more.

Both genders are equally responsible for the causes of infertility. About 45 percent of couples face infertility problems as it not only limited to women, the most common problems men face are low sperm count, morphology abnormalities and low motility of sperm. Several factors contribute to infertility including ovulatory problems, hormonal changes, environmental changes etc.

Evaluating and treating male fertility has number of problems, the basic lack of tests standards for accessing fertility. Even if all known tests are normal there can be unexplained infertility, as semen is exquisitely sensitive to storage conditions and often proper guidelines are not followed in reporting. Male infertility is a debated topic and there is no concrete knowledge about its pathophysiology.

The male partner accounts for the infertility 40% of the time, 40% from the female partner as well and 20% shared by both the man and the woman. The factors involve congenital, hormonal, morphological and immunological disorders.^4,5

Unexplained Infertiity (UI) is diagnosed in a couple when the standard investigations including the semen analyses, test of ovulation and tubal potency do not provide specific results or do not detect any abnormality. The prevalence of UI reaches up to 30% of infertile couples with regards to standard investigation.

Extensive endometriosis can devastate the reproductive capability. Minor endometriosis do not induce infertility. It has been reported that approximately 20% of infertile females suffer from tubal disease, either distal or peritubal.^6,7

The first line immunosuppressants used include Cyclosporine, tacrolimus, and sirolimus which have resulted in a drastic improvement in the health outcomes of renal transplant patients for the past years. Most of this mediations should be used for a long period of time and has caused many health risks like diseases of cardiovascular system, cancer and infertility. As a result of this side effects a late mortality and dysfunction of allograft trends has developed. Human studies as well as animal models have showed that use of immunosuppressant drugs can hazardous to germ cells and can cause dysfunction in the formation of sperms and gonadal function in male. The amount of sperms and its life expectancy is inversely proportional to the cyclosporine blood levels. Renal transplant patients using sirolimus has reported dysfunction of gonads.^8,9,10

In case of inflammatory and auto immune disorders, immunosuppressant’s are the first drug of choice which is prescribed in young and also elderly patients, and constant use of this medications for a long time has caused adverse effects on pregnancy, fertility and has caused a decline in reproductive trends.

Immunosuppressant’s are widely used from the late 21^st century for a variety of indications. The physicians long back had knowledge about the side effects and action of these drugs. Immense exposure in this field had provided better understanding of the root cause. Handling of this drug should be done with caution and side effects during long term treatment should be monitored.¹¹

METHODS:

An extensive search on Pub Med was conducted using the terms such as ‘Infertility and immunosuppressant’, and other related terms such as ‘ovulation’, ‘pregnancy’, ‘spermatogenesis’. Rather than this, additional information was also obtained from the reference list of selected articles. The search was not restricted exclusively to human subjects, neither to a type of disease or condition, to gather all available studies with regards to this topic. All published articles on immunosuppressant and infertility, written in English and published until January 2018, were screened for eligibility.

SULFASALAZIE AND INFERTILITY:

Sulfasalazine and 5-aminosalicylates (5-ASAs) have been used for the initial treatment of IBD and for long term maintenance of disease remission. These drugs have anti-inflammatory activity. The effect of sulfasalazine was studied in 28 patients with inflammatory bowel disorder. The daily dose of the drug used was 2-4 g/day. Semen was examined for changes in density, motility, and morphology before, during, and after withdrawal of sulfasalazine.

Out of 28 patients, only 18 of them used this medication for two months or more than that. Sulfasalazine was withdrawn from the treatment and about 10 patients reported their conception after the withhold of this drugs for past 2 months. Preliminary endocrine and acetylator phenotype studies do not elucidate the mechanism of this important new side-effect of this drug. This study proved the time relationship between the use of this drug and its ill effect on the sperm count. As reported in many studies sulfasalazine and its metabolites are highly dangerous to sperm production. These studies confirmed the preliminary report and suggest that prolonged treatment with sulfasalazine may universally depress semen quality and cause reversible infertility.¹²

Levi et al first reported 4 cases of male infertility associated with sulfasalazine in 1979. Withdrawal of Sulfasalazine therapy has showed 100 percent successful pregnancy. Subsequent studies showed that this medication causes reversible non-dose-dependent quantitative and qualitative abnormalities of sperm in > 80% of men.^13,14

Birnie et al¹⁵did a study on 21 chrons disease patients who was under the sulfasalazine therapy and among that 18 patients had alterations in semen analysis.

Another study by Moody et al¹⁶ reported that almost 25% of the men with inflammatory bowel disorder (IBD) had no children’s while comparing to male general population.

They also found that 60% of male IBD patients who had no children were taking sulfasalazine. Sulfasalazine is a molecule that has two components: 5-ASA and sulfapyridine. The sulfapyridine metabolite is thought to be responsible for adverse effects on sperm, causing impaired sperm maturation or oxidative stress production.^{15,16,17,19,20}

Wu et al²¹ found no correlation between reactive oxygen species production and sperm density, sperm motility, or hamster oocyte penetration capacity. The adverse effects

of sulfasalazine on sperm have been shown to be fully reversible after discontinuation.^22,23

Restoration of semen quality and fertility has also been shown afters witching to a different 5-ASA compound without the sulfapyridine component, such as mesalazine (also called mesalamine).^24,25

Zelissen et al ²⁶ had done a study in 11 IBD patients under sulfasalazine treatment, the semen quality of the patients were analysed and 4 more after replacing sulfasalazine with an oral slow-release preparation of 5-ASA, and observed significant improvements in sperm count, morphology, and motility during 5-ASA treatment in comparison with sulfasalazine treatment. Surprisingly 3 pregnancies was reported during the study period. On the other hand, there is a case report of mesalazine-induced oligozoospermia in a young man with UC. In that case, semen analysis results returned to near normal and pregnancy occurred after mesalazine treatment was stopped, but the patient’s semen parameters worsened after resuming mesalazine.²⁷

A retrospective study on 1255 males under the mesalazine treatments was recorded, the total count of sperms and sperm motility was increased after withdrawal of mesalazine.²⁸ Also 6 patients was reported to be pregnant after the drug was discontinued.

Similarly decreases in testosterone have been reported in men receiving corticosteroids to minimize transplant rejection; however, most were treated with multiple immunosuppressive medications that may have contributed to this effect. A large number of trials of healthy men treated with corticosteroids have shown some disruption in reproductive hormone levels, but other studies reported no effect. Studies in monkeys, rats (at human equivalent dose), cattle, sheep, and horses have shown endocrine disruption, including low testosterone with dexamethasone treatment. Of the cytostatic immunosuppressives, which have high potential for cellular damage, cyclophosphamide has received the most attention, sometimes lowering sperm counts significantly. Methotrexate may decrease sperm numbers in humans and has significant negative impacts in rodents. Other chemotherapeutic drugs used as immunosuppressants are likely to impact negatively on male fertility endpoints, but few data have been collected. The TNF-α Inhibitors have also received little experimental attention. There is some evidence that the immunophilin modulators: cyclosporine, sirolimus, and everolimus cause endocrine disruption and semen quality impairment.^29,30

THE EFFECT OF AZATHIOPRINE (AZA) ON FERTIITY:

Chronic inflammatory disease consist of Crohn’s disease (CD) and ulcerative colitis (UC) which commonly affects young adults in the reproductive age. Inflammatory bower diseases (IBD) roots from cellular and immune inflammatory reactions and the mainstream treatment include immunosuppressants.^31-35AZA have become the treatment of choice to maintain remission in patients with refractory courses of IBD.4,5 AZA provides steroid-sparing efficacy, may lead to mucosal healing in severe recurrent Crohn’s ileitis, and has been shown to close fistulas in two thirds of patients.^36,37AZA is usually administered for several months up to years because of its slow onset of action and long-term efficacy and the excellent tolerance of AZA in most patients. Recent data support continuous AZA treatment to preserve remission in patients with IBD and reject discontinuation because of high risk of relapse.^38-42AZA is a prodrug, rapidly converted to 6-MP and further to its active metabolites the 6-thioguanine nucleotides, which interact in purine metabolism. Although AZA has shown some teratogenicity in animals, it has been considered unlikely to be a mutagen in humans. Data on pregnancy outcomes of renal transplant patients receiving AZA show no increased incidence of congenital malformations or miscarriages. AZA treatment during pregnancy in IBD patients seems to be safe and may be continued. However, no data are available on the influence of AZA treatment on male fertility. We performed this prospective study to investigate the influence of AZA therapy on semen quality in patients with IBD.^43-48

A study was conducted to analyse the effect of AZP on fertility. The quality of semen was studied and compared with the standards of World Health Organization (WHO) regarding sperm density (Mio/mL), motility, morphology, ejaculation volume (mL), and total sperm count.28 Motility was expressed as percentage of sperm with forward progression (sum of sperm with fast linear progression and slow progression), and morphology was expressed as percentage of sperm with normal form. Semen samples were obtained by masturbation in the privacy of a room near the laboratory after at least 3 days of sexual abstinence. The ejaculate was collected in a clean, wide-mouthed container made of polypropylene and analyzed within 2 hours of emission. In 10 of 23 patients, a semen sample was assessed before and during AZA treatment. Semen analysis was performed twice during at least 2 years of AZA administration in 5 of 23 patients to evaluate a possible toxic long-term effect.

During the study period, 6 of the patients receiving AZA fathered 7 healthy children. No fetal abnormalities were found at delivery, and the perinatal outcome was normal. At this time, all children (age 1–3years) have unremarkable growth and development. One spontaneous abortion occurred in a twin pregnancy; in this case, the patient was a smoker and received concomitant therapy with sulfasalazine. In this study the semen analyses show diminished semen density in 1 (6%) of 18, decreased motility and morphology in 6 (33%) of 18 as well as reduced ejaculate volume in 2 (11%) of 18 and total sperm count in 1 (6%) of 18 IBD patients with AZA treatment. However, in 10 of these patients who had semen analysis performed before AZA administration, semen parameters were also found to be partly decreased compared with WHO standards. This finding is in line with previous studies that reported impaired semen quality in patients with CD.^49,50,51

Three studies have shown that AZA does not adversely affect fertility in women and does not have to be discontinued during pregnancy. For men, no guidelines have been established for whether AZA treatment should be discontinued in the case of planned conception. One recent study reported an increased incidence of pregnancy-related complications when fertilization had occurred within 3 months of 6-MP use by the father, although these data have been discussed controversially. It is currently questionable whether recommendations for discontinuing AZA or 6-MP administration in men wishing for their partners to conceive are justified.^52,53

DISCUSSION:

Fertility in men with inflammatory bowel disease (IBD) was examined by Narendranathan et al 54 to determine reported deficit in pregnancies in their wives was due to reduced reproductive capacity. The case contained 106 men having Crohn’s disease and 62 people had Ulcerative colitis from the rosters of North Carolina chapters of the National foundation for Ileitis and Colitis. Neighbour identified in this cases where 140, Wife’s of men with Crohn’s disease with pregnancy were about 186 among which 110 where from ulcerative colitis group, and 300 among the control groups. The actual mean number pregnancy in Crohn’s disease patients is (1.75 +/- 0.12) was very lower than that of number of controls 2.14 +/- 0.11), p less than 0.02. If we check the mean of the number of pregnancies with patients having ulcerative colitis is not very different from controls (p less than 0.07). This study concludes that overall reproductivity of the male patient was not changed drastically even after the use of immunosuppressive therapy.

Laren et al⁵⁵conducted a retrospective cohort study on 48 women with infertility undergoing ovarian stimulation after receiving methotrexate (MXT) treatment for ectopic gestation. After the 2 years of treatment with methotrexate intra uterine pregnancy rate was around 43% and a decrease in the level of oocytes was observed after the treatment and the study concluded that the methotrexate affect the oocytes production. MTX is a folic acid derivate which was discovered in early 90’s with a potent antibacterial and antifungal properties.^56,57,58,59

Aminopterin and methotrexate are both folate analogue as well as antagonist and this folates are used for transferring of carbon units which are essential for synthesis of amino acids and purines. The enzyme dihydrofolate reductase (DHFR) is reversibly inhibited by MTX. Folic acid is reduced to tetrahydrofolic by DFHR, and hence MTX reduces the availability of one-carbon fragments which is necessary for the synthesis of purines due to this deoxyuridylate to thymidylate is limited in the synthesis of DNA and cell reproduction. MTX is further metabolized to MTX polyglutamases, long-lived metabolites which also inhibit other folate-dependent enzymes.^60,61 For normal development Folic acid is needed and its lack may be harmful during the pregnancy by the inhibition of folic acid and its ations of MTX are mediated then we might get clue due to lack of folic acid during pregnancy what is the effect of MTX in fetus. MXT used to treat cancer, psoriasis, and rheumatic diseases, is a folic acid antagonist that binds to the enzyme dihydrofolate reductase. This inhibits synthesis of thymidylate, serine, and methionine, which disrupts sythesis of DNA, RNA, and protein and leads to cell death. Mechanism of action of MXT has been studied and suggest that it acts by attacking the cells during cell division and gradually results in a decline in production of spermatozoa.

Cells undergoing division, may be killed or damaged by Methotrexate which is a process continually occurs during spermatozoa. Till today there are no solid published report of adverse pregnancy outcomes mostly men’s exposed to MTX before conception. Opinions in the literature differ on the effects of methotrexate on male fertility. But many studies have different conclusion about the effect of MXT on fertility. During 1970 a case report was published which reported that no change was observes in sperm concentration and motility in 11 patient who underwent MXT therapy.⁶²A study was conducted by Grunnet et al⁶³ to compare the ejaculates of 10 men using topical corticosteroids for severe psoriasis with 10 men using methotrexate therapy for the same indication. There are no serious effects of MTX on men’s semen quality. The result showed that men treated with methotrexate were more likely than men treated with corticosteroids to have normal semen.

De Luca et al⁶⁴ also reported minimal to no suppression of spermatogenesis with methotrexate therapy. A study by Bacci et al⁶⁴ studied the long-term effects of combination chemotherapy for osteosarcoma.

Methotrexate and other chemotherapeutic agents are present in all chemotherapy regimens. 10 out of 12 men who did spermatography was confirmed with Azoospermia. Nine out of those 10 where administered etoposide and ifosfamide as their part of chemotherapeutic regimens. It has been found that even few dose of alkylating agent such as Ifosfamide can result in permanent azoospermia.

A case series was published by Siimes et al⁶⁶ as part of a chemotherapeutic regimen for treating osteosarcoma 18 men received high dose of MTX. Seven person regimen contained cisplatin and other rest didn’t contained cisplatin. Cisplatin’s mechanism is also believed to have alkylation of DNA. Those who had cisplatin was reported to have lower sperm count and testicular volume compared to the group who didn’t had cisplatin in there regimen. The other group having 11 men those who didn’t had cisplatin in there regimen following the treatment of chemotherapy for osteosarcoma five men had normal sperm count.

Yeuhi chen et al⁶⁷comparative study demonstrates that long-term oral administration of commonly used immunosuppressants at therapeutic doses has various effects on male reproductive system in rats subjected to unilateral nephrectomy, which is physiologically and clinically relevant to postrenal transplant state in humans. Cyclosporine and sirolimus caused significant testicular injury and profound alterations on the hypothalamic-pituitary-gonadal axis, resulting in severe impairment of spermatogenesis and likely male infertility. Tacrolimus, on the other hand, induced only mild changes of spermatogenesis without histological evidence of testicular injury. This finding where a great help to provide important information for evaluation of male infertility and selecting of immunosuppressive regimens for those who wish to have parenthood after renal transplant.

Nakawaga et al⁶⁸conducted a prospective cohort study to evaluate the clinical efficacy of immunosuppressive treatment with tacrolimus for repeated implantation failure (RIF) patients who have elevated in T helper (Th1)/Th2 cytokine producing cell ratios. 25 person were treated with tacrolimus. And seventeen people didn’t got any treatment. Group which were treated got tacrolimus two days before embryo transfer and continued till the pregnancy test for an aggregate of 16 days. Daily dose where determined by the degree of Th1/Th2 cell ratio which is approximate 1 to 3 mg. The group which were treated had a clinical pregnancy rate of 64.0%, which is higher than that of control group which was 0% (P<0.0001). The group which were treated in that the miscarriage rate was 6.3% and the live birthrate was 60.0% (P<0.0001). No side effect was found in treatment groups consuming tacrolimus. None had obstetrical complications during pregnancy. This study concluded that the immunosuppressive treatment using tacrolimus improved pregnancy outcome of repeated implantation failure patients with elevated Th1/Th2 ratios.

CONCLUSION:

Infertility can have drastic effects on couple’s lives hence, it is important to improve their reproductive health issue. The above study clearly demonstrates that commonly used immunosuppressants have various impacts on male reproductive system even at therapeutic levels. On the basis of the limited data available, fertility after low-dose MTX would seem to be only marginally affected. Chronic ingestion of sulfasalazine in the human is associated with abnormal semen quality. At the time of prescription, patients must be informed of the possible consequences of immunosuppressants on fertility and of the need for contraception. Pregnancy must be planned and the treatment modified if necessary in a pre-conception time period adapted to the half-life of the drug, imperatively in relation with the prescriber of the immunosuppressive drugs

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Received on 18.11.2018 Modified on 27.12.2018

Research J. Pharm. and Tech. 2019; 12(3): 1441-1447.

DOI: 10.5958/0974-360X.2019.00239.7