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Guidelines for risk reduction when handling gametes from infectious patients seeking assisted reproductive technologies
Reproductive BioMedicine Online, Volume 33, Issue 2, August 2016, Pages 121 - 130
This article presents guidelines for risk reduction when handling gametes from infectious patients, including those with Hepatitis B, Hepatitis C, HIV, HCV, Ebola virus and Zica virus.
According to the Americans with Disabilities Act (1990), couples with blood-borne viruses that lead to infectious disease cannot be denied fertility treatment as long as the direct threat to the health and safety of others can be reduced or eliminated by a modification of policies or procedures. Three types of infectious patients are commonly discussed in the context of fertility treatment: those with human immunodeficiency virus (HIV), hepatitis C or hepatitis B. Seventy-five per cent of hepatitis C or HIV positive men and women are in their reproductive years, and these couples look to assisted reproductive techniques for risk reduction in conceiving a pregnancy. In many cases, only one partner is infected. Legal and ethical questions about treatment of infectious patients aside, the question most asked by clinical embryologists and andrologists is: “What are the laboratory protocols for working with gametes and embryos from patients with infectious disease?” The serostatus of each patient is the key that informs appropriate treatments. This guidance document describes protocols for handling gametes from seroconcordant and serodiscordant couples with infectious disease. With minor modifications, infectious patients with stable disease status and undetectable or low viral load can be accommodated in the IVF laboratory.
Keywords: hepatitis C, hepatitis B, HIV, IVF, sperm purification, standard precautions.
Around 4.2 million people of childbearing age in the USA are infected with HIV, hepatitis C (HCV), hepatitis B (HBV), or a combination. For those seeking assisted reproductive techniques, laboratory protocols can be developed to safely accommodate virus-positive patients. These protocols will reduce the risk of infection to the staff, to the patients themselves and to other patients. The main risk to clinical staff is through needle punctures and splash or aerosol exposures. The risk to laboratory staff may come at the time of oocyte retrieval when blood products are introduced into the laboratory; at the time of semen processing; at the time of in-vitro insemination; during culture of gametes and embryos; and at the time of cryopreservation of oocytes, embryos or sperm. Patients may be exposed to risk if protocols are not in place to prevent cross-contamination of samples or if protocols are not strictly followed. Unsafe procedures include improper labelling of containers, inadequate sanitation between patients, improper handling of body fluids and use of blood products contaminated with infective agents.
Control of disease transmission requires a team management approach. It is critical to have open communication among the laboratory and clinical staff about protocols, testing, tests results, precautions and care offered to the patient. It is essential that universal or standard precautions be observed at all times. That is, all tissues and cells should be handled as if they are from an infectious patient. Each fertility programme should determine its comfort level with handling gametes from infectious patients. These patients are entitled to fertility options, so caution and appropriate modification on the part of the laboratory staff is required whenever possible. In this guideline, handling gametes and embryos from patients with HIV, HBV and HCV will be discussed (Table 1).
Blood-borne viruses that can be sexually transmitted and are routinely screened in fertility couples.
|Name of virus||Virus type and target|
|Human immunodeficiency virus types 1 and 2||Retrovirus primarily infects helper T-cells (CD4) causing immunodeficiency syndrome.|
|Hepatitis C virus||RNA virus infects liver cells.|
|Hepatitis B virus||Double-stranded DNA virus infects liver cells.|
|Human T-lymphotrophic virus I and II||Retrovirus primarily infects CD4 T-cells causing adult T-cell leukaemia and myelopathy.|
|Cytomegalovirus||Herpes virus threatens immunocompromised individuals and is leading cause of congenital infection.|
Published guidelines on laboratory safety when handling gametes from infected patients are limited and do not offer comprehensive hands-on recommendations for laboratory staff (Clarke, 1999, Gilling-Smith et al, 2005, and Practice Committee of American Society for Reproductive Medicine, 2013).
The European Society of Human Reproduction and Embryology Committee of the Special Interest Group on Embryology published guidelines for good practice in IVF laboratories (Magli et al, 2008), recommending treatment of patients infected with HIV, HBV or HCV using dedicated laboratory space at allocated times, and processing within a biosafety cabinet to prevent cross-contamination of patient specimens.
The Practice Committee of American Society for Reproductive Medicine (ASRM) (2013) recently issued guidelines for treating patients with infectious disease. These guidelines advise counselling, education and informed consent, and provide standards for screening sperm and egg donors. The ASRM also recommends separation in time or space, separate frozen storage and special sperm washing with viral check before freezing, if possible.
The United States Food and Drug Administration regulates third-party reproductive tissues, including sperm, oocytes and embryos as products for transplantation. Regulations include donor screening for infectious diseases, as well as quarantine, storage and labelling requirements.
The Human Fertilization and Embryology Act of the UK mandates separate frozen storage for sperm, oocytes and embryos for which the source patient tests positive for infectious disease. Heat-sealed cryopreservation straws are used by most European IVF centres treating HIV and HBV and HCV positive patients with no reported cases of cross-contamination (Clarke, 1999).
In the case of HIV, no vaccine is available (Mascola, 2015). The HIV virus uses reverse transcriptase to transcribe RNA into DNA (Schnittman and Fauci, 1994). Once the virus binds to the cell surface, commonly that of the helper T-cell (CD4+) of the immune system, and fuses with the cell, the viral RNA is reverse transcribed into DNA that combines with the host cell DNA. Some infected CD4+ cells in lymphoid tissues destroy themselves, leading to falling CD4+ counts over time (Doitsh et al, 2014 and Monroe et al, 2014). When the serum CD4+ count falls below 200 per mm3 (or about a drop of blood), HIV infection can become acquired immunodeficiency syndrome. The lymph nodes are infected by HIV, which travels into the blood to gain entrance to other body fluids, such as semen and breast milk (Schnittman and Fauci, 1994). HIV is typically detected in the serum, and the viral load is expressed as viral RNA copies per ml of serum, measured by polymerase chain reaction (PCR) assay (Hart et al., 1988).
Is HIV associated with the sperm cell?
Although many are convinced that HIV is not associated with sperm cells selected by gradient separation (Anderson et al, 2010, Gilling-Smith et al, 2006, and Le Tortorec, Dejucq-Rainsford, 2010), controversy remains. Convincing evidence was published by (Quayle et al, 1997) and (Quayle et al, 1998) reporting no association of HIV with motile sperm collected by gradient separation followed by swim-up. Both immunohistochemical and nested PCR failed to detect HIV associated with sperm. However, HIV, was found free in seminal plasma and was associated with leukocytes (white blood cells). Further research found that HIV receptors CD4, CXCR4, CCR5, which are involved in HIV infection of leukocytes, are not present on the sperm surface (Kim et al., 1999), although HIV can attach avidly to sperm apparently via sperm surface mannose or heparin sulphate receptors (Bandivdekar et al, 2003, Ceballos et al, 2009, and Fanibunda et al, 2008), which may be important for HIV transmission in vivo.
Conversely, some older studies suggest that HIV may be associated with germinal cells in the testis (Shevchuk et al., 1998). Although the use of electron microscopy and atomic force microscopy that HIV is found in motile sperm from HIV-infected men selected by gradient followed by swim-up, HIV can enter the sperm in vitro. It can transfer to oocytes, as the virus was found in eight-cell embryos after IVF (Baccetti et al, 1991, Baccetti et al, 1994, and Barboza et al, 2004).
More recent work has shown that even after complete elimination of non-sperm cells, sperm with gross morphological abnormalities are positive for HIV (Muciaccia et al., 2007).
Leukocytes in semen are the main mode of HIV infection (Nicopoullos et al., 2010). It is important to recognize that serum viral load is not always correlated with semen viral load (Coombs et al., 1998). Even if HIV seropositive males receive highly active anti-retroviral therapy (HAART) and have serum viral loads below the detection limit of the assay, semen samples from these men may still test positive for HIV (Ferraretto et al, 2014, Lambert-Niclot et al, 2012, and Politch et al, 2012).
Hepatitis C infection
About 1% of the global population is infected with HCV. Although a virtual cure for HCV has been recently developed, it is extremely costly with limited usage at this time. An HCV vaccine is still not available (Li and Lo, 2015), so patients with chronic HCV infection who have not been prescribed the cure may seek fertility treatment. HCV viral RNA in serum is quantified by PCR assay as international units (IU)/ml. In general, about 90% of HCV RNA positive samples have a viral load above 10,000 IU/ml (Fytili et al., 2007). In contrast to HIV, HCV can profoundly reduce semen quality (Lorusso et al., 2010).
Hepatitis B infection
One of the major causes of liver disease worldwide is HBV, which is a DNA virus. It occurs in acute and chronic forms, and is about 100 times more infective by parenteral exposure (e.g. needle stick) than HIV. A HBV vaccination has been available since 1981 and its efficacy is measured by a HBV surface antibody (sAb) titre of 10 mIU/ml or greater (Greub et al., 2001). In the case of HBV infection of either the male or female partner, the reasonable precaution is to have all laboratory staff vaccinated for HBV. In discordant couples, vaccination of the uninfected partner is indicated. The effects of HBV on sperm quality have not been widely studied. In one study, however, semen parameters concentration, motility, viability and morphology from HBV-positive men were all significantly reduced compared with semen from virus-negative men (Lorusso et al., 2010).
Ebola virus and Zika virus
In the context of global travel, new and potentially untreatable viruses that can lead to serious infectious disease are being seen for the first time in the USA, including in couples of reproductive age. Treatment of these couples should at all times follow the latest guidance issued by the Centers for Disease Control and by ASRM. The 2014 Ebola outbreak in select regions of West Africa was the largest in history. At this time, no specific treatment is available, only experimental agents (www.who.int/ebola). No studies have been published on the safe handling of semen infected with Ebola virus. Because of catastrophic outcomes for mothers and fetuses affected with Ebola, patients should wait 21 days after their return from an Ebola-infected country before receiving infertility treatment. As they will be monitoring their own symptoms and self-quarantining, waiting 21 days is a realistic recommendation (Affairs, 2014).
Men and women exposed to the Zika virus may have no symptoms or mild symptoms but the effect of Zika viral infection on a fetus in utero is similarly catastrophic. According to the Centers for Disease control, women who have Zika virus disease should wait at least 8 weeks after symptom onset to attempt conception, and men with Zika virus disease should wait at least 6 months after symptom onset to attempt conception. Women and men with possible exposure to the Zika virus but without clinical illness consistent with Zika virus disease should wait at least 8 weeks after exposure to attempt conception. At present no data or recommendations are available for purifying sperm away from these viruses in semen; all counselling, precautions and procedures recommended for other viruses should be followed if there is any suspicion of infection.
Assisted reproduction techniques and risk reduction
A checklist of good laboratory practice and potential modifications to reduce risk when handling gametes from virus-positive patients in the laboratory is presented in Table 2. These include using universal precautions, using personal protection equipment, minimizing aerosol formation during sample processing and properly decontaminating the work area. Regardless of viral status, it is recommended that these precautions be in place for each patient as part of good laboratory practice.
Checklist for minimizing risk of bloodborne pathogen transmission when handling gametes from infectious patients.
The “gold standard” we recommend for handling HIV-discordant couples in a fertility clinic, in which the male is HIV-seropositive and the female is HIV-seronegative is presented in Table 3. We strongly recommend this as the standard of care for couples composed of HIV seropositive males and seronegative females. Generally, the disease should be stable and the viral load in the serum should be undetectable (40–75 viral copies/ml of blood). Patients with chronic detectable viral load in the serum, however, may also seek fertility treatment through assisted reproduction techniques. If possible, these patients should be treated with HAART under the care of an infectious disease specialist until viral load and CD4+ count are within acceptable limits for assisted reproduction, generally taken as viral load less than 200 copies/ml and CD4 count greater than 250 cells/mm3 for the preceding 6-month period. Note that patients within the first 6 months of detectable disease have the highest infectivity. Patients unable to attain this control of their disease should be considered on a case-by-case basis in order to ensure management of infection risks and appropriate counselling and communication. It is not recommended that patients with detectable viral load in the serum be brought through the laboratory for semen processing for establishing a pregnancy in a seronegative partner.
Standard for treating a male patient who is HIV-positive and his HIV-negative female partner.
HIV, human immunodeficiency virus.
If the female partner is HIV-positive or HCV-positive, fertility options may include intrauterine insemination (IUI) or IVF, or intracytoplasmic sperm injection without fear of infecting her male partner. Vertical transmission refers to mother-to-child-transmission of virus, bacteria or parasite to the embryo, to the fetus during pregnancy, to the baby during childbirth, or both. The potential for vertical transmission of the virus to her child should be considered and the patient counselled appropriately. Both HIV and HCV can be transmitted to the fetus in utero and at birth. Appropriate medical management of the pregnant patient has reduced vertical transmission of HIV to less than 2% (Practice Committee of American Society for Reproductive Medicine, 2013). The rate of vertical transmission of HCV, however, averages 5%, with significant variation among study populations (Benova et al., 2014).
If the HIV-positive or HCV-positive female patient seeks insemination via IUI, there is no burden on the laboratory regarding processing of female gametes. If IVF or intracytoplasmic sperm injection (ICSI) is indicated, virus-positive oocytes should be handled according to the recommendations set out in Table 4. For women who are HIV, HCV or HBV positive, ICSI is recommended over IVF, to reduce the number of granulosa and cumulus cells in culture and to reduce handling of those cells by embryologists. Hepatitis C virus has been measured in follicular fluid and may attach to granulosa cells. Devaux et al. (2003) showed in 17 HCV-positive women that Hepatitis C RNA was detected by PCR in 89% of follicular fluid samples. After denuding the oocytes of granulosa cells, inseminating the oocytes via ICSI, washing the oocytes and embryos and refreshing the media during culture, the viral load became undetectable, irrespective of the original follicular fluid status. Therefore, the authors concluded that follicular fluid must be considered as potentially infected, but all oocytes can be inseminated by ICSI resulting in virus-free embryos in culture. In a smaller study, Papaxanthos-Roche et al. (2004) found HCV associated with unfertilized oocytes denuded of follicular cells.
Recommendations for handling virus-positive oocytes in the IVF laboratory.
HIV, human immunodeficiency virus; ICSI, intracytoplasmic sperm injection.
According to the Centers for Disease Control and Prevention guidance document published in 2014, couples in the USA with a virus-positive male may use IUI, IVF or ICSI if the virus-positive semen has undergone procedures that remove seminal fluid that may contain HIV (sperm washing) (Centers for Disease Control and Prevention et al, 2014). If the male partner is HIV positive, and the patients are good candidates for IUI, special washing of the sperm is a safe, cost-effective treatment method that is widely used (Barnes et al, 2014 and Moragianni, 2014). The concern is that, although cases have been confirmed of post-wash contamination (with zero reports of infection of women or babies in over 8000 IUI cycles with washed sperm), there is no way to guarantee that HIV viral particles are not present in the final sample for IUI. Detection of virus is dependent on in-house PCR methods developed and used. In infected cells in the semen, HIV DNA may be detected, and viral RNA may be free or cell associated. Detection of viral RNA may represent non-infectious small RNAs that are not part of a viral particle. A guideline should be developed at each IVF programme to define the lowest acceptable level of virus in samples to be used for insemination, based on local PCR methods and sensitivity, and physicians' and ethics committee recommendations.
Additionally, the use of sperm from a seropositive partner to inseminate a woman who is seronegative, particularly for HIV, may be dictated by US state law. Richardson et al. (2015) details each US state's laws specific to HIV up to the present time . In general, these laws are meant to prohibit HIV-positive individuals from donating their blood, organs and tissues, and from selling their semen. To date, no criminal charges have been brought against a specific clinic or individual that processes known HIV-positive semen for IUI in a HIV-negative female. Because of the coverage of an HIV-positive individual under the Americans with Disabilities Act, laws that would specifically limit a serodiscordant couple's right to procreate and use infertility services would face an uphill battle. The law is always changing and is dependent on the state in which the couple seeks assisted reproduction technique treatment. Fertility clinics intending to perform such procedures should first seek legal counsel to ensure that they do not unwittingly break the law. Men who are HCV-positive have not been restricted in the USA from IUI as have HIV-positive men. At present, IUI is offered to couples in which the man is infected with HBV or HCV, without the legal and regulatory issues applied to HIV.
If semen analysis is carried out at a clinic, it should also be available for known virus-positive men. No special expertise or equipment is required other than that used with universal or standard precautions. It is not necessary to notify other patients that virus-positive specimens are processed in your laboratory. Appropriate procedures and sanitation are in place to control for cross-contamination. As an analogy, a patient who is scheduled for surgery does not need to be notified that surgeries are being carried out on virus-positive patients using the same facilities and instruments.
Special washing of semen for virus-positive men
Recommendations for the laboratory handling of virus-positive (HIV, HCV, HBV) semen are presented in Table 5. In processing semen that is virus-positive, the goal is to greatly reduce the viral titre that can be measured in the final sample by PCR. Many peer-reviewed articles have described the use of special sperm washing protocols effective in removing HIV from motile sperm for IUI, IVF or ICSI. In none of these procedures has there been seroconversion of the female partner or babies born (Nicopoullos et al, 2004, Nicopoullos et al, 2010, Savasi et al, 2007, Schuffner et al, 2011, Semprini et al, 1992, Semprini et al, 2013, Vitorino et al, 2011, and Zafer et al, 2016). Special washing refers to an additional swim-up step of sperm from the pellet that results from the density gradient. The swim-up step into clean media further separates the sperm from any leukocytes in the pellet, resulting in a cleaner sperm sample for insemination.
Recommendations for handling virus-positive semen in the IVF laboraotory.
In 2003, some of the larger centres providing sperm washing for HIV-discordant couples joined together to form the Centres for Reproductive Assistance Techniques to HIV Couples in Europe (CREAThE), featuring centres in the UK, Italy, France, Belgium, Spain, Italy, Switzerland and Israel. By 2006, over 2800 cases of IUI, IVF and ICSI involving HIV-negative women and sperm separated from the semen of their HIV-positive partners had been reported, with none of the women or the hundreds of children born getting infected (Bujan et al., 2007). A recent systematic review (Barnes et al., 2014) accounted for 8212 IUI and 1888 IVF or ICSI cycles with no seroconversion of HIV-seronegative female partners or any of the offspring.
Much less clinical research has been conducted for assisted reproduction in HCV-discordant couples than there has been for HIV. For HCV-positive males with detectable viral load in the serum, the density gradient with swim-up protocol (Garrido et al, 2004, Mencaglia et al, 2005, and Pasquier et al, 2000) can be used before IUI or ICSI to reduce the viral titre in the final sperm sample. The infected partner can be treated with peginterferon alfa and ribavirin to reduce viral load before assisted reproduction (Nie et al., 2011). Treatment should be used for 48 weeks, during which time two forms of contraception should be used followed by a 6-month washout period to reduce the teratogenic and embryocidal risks of ribavirin, which is a pregnancy category X drug. No PCR of the final semen sample is recommended at this time for HCV positive men.
A small number of people vaccinated against HBV do not produce anti-hepatitis B surface antibody titre levels detectable by commercial assays. Others lose detectable anti-hepatitis antibodies at some point after vaccination. The risk for these “non-responders” becoming infected with HBV or developing clinical hepatitis B is not well defined. If the female patient is a “non-responder” with a partner who is HBV-positive, she may still be protected against hepatitis B infection after insemination owing to antibody titres below the assay detection limit (less than 1.5 mIU/ml) (Greub et al., 2001). If a seronegative patient desires pregnancy with her seropositive partner, special sperm washing is recommended as described above to reduce the titre of HBV in the final sample. No PCR of the final semen sample is recommended at this time for HBV positive men.
Risk of vertical transmission
With special washing of sperm from HIV seropositive men and insemination of HIV seronegative women in thousands of assisted reproduction technique cycles, no cases have been reported of seroconversion of the female or vertical transmission of the virus from the seronegative mother to the resulting offspring (Barnes et al, 2014 and Zafer et al, 2016). In cases in which the female patient is HIV positive at the time of the assisted reproduction technique cycle, combined antepartum, intrapartum, and infant antiretroviral prophylaxis are recommended to reduce perinatal transmission by several mechanisms, including lowering maternal viral load and providing infant pre- and post-exposure prophylaxis. A cesarean delivery should be scheduled at 38 weeks with intravenous antiretroviral drugs. Finally, oral antiretroviral drugs should generally be given for at least 6 weeks to all infants perinatally exposed to HIV to reduce perinatal transmission of HIV (Chappell and Cohn, 2014).
Vertical transmission of HCV is possible; even when every effort is made to produce a virus-free embryo by assisted reproduction techniques, the fetus may become infected in utero or at birth (Benova et al., 2014). The prevalence of paediatric HCV infection varies between 0.05% and 0.36% in developed countries and between 1.8% and 5% in the developing world. No preventive intervention is available. Spontaneous viral clearance takes place in 25% of infected children within 6 years of age. Chronic infection has a mild to moderate course in most children, although severe liver damage may develop (Tovo et al, 2016 and Yeung et al, 2014). In the context of IVF, in a single study of 30 women positive for HCV antibodies treated with ICSI, one out of 30 newborns tested positive for HCV antibody and HCV RNA (Nesrine and Saleh, 2012).
Maternal infection with either HBV or HCV has been linked to adverse pregnancy and birth outcomes, including MTCT. In the case of HBV, MTCT has been reduced to about 5% overall in countries, including the USA, that have instituted postpartum neonatal HBV vaccination and immunoprophylaxis with hepatitis B immunoglobulin (Dunkelberg et al., 2014). In analysing IVF cycles from HBV men and women, Nie et al. (2011) suggested that the sperm and oocytes may act as vectors for the vertical transmission of HBV to the embryos, but the presence of HBV surface antigen in oocytes and embryos may not result in the vertical transmission of HBV in the offspring of HBV carriers (Jin et al., 2015).
Cryopreserving semen positive for HIV or HCV
Ideally, patients who freeze autologous sperm are tested for infectious disease status. Viral load should be measured and found undetectable. If frozen in heat-sealed and leak-proof CBS High Security straws (CryoBiology), sperm can be stored safely on-site. If no CBS straws, confirm that positive infectious disease status sperm will be accepted at a long-term storage facility, then freeze in regular cryovials and store in quarantine tank until moved off-site. Use 1% bleach to decontaminate the tank after use.
Additional protocols for processing virus-positive semen
PCR testing for HIV
As a quality control for the procedure and to protect the programme from medico-legal action, an aliquot of washed sperm (about 100 µL) may be tested for detectable HIV RNA before the sample being used for treatment. No test for HIV in sperm suspensions is commercially available. About 3–8% of washed semen specimens from men with virus-positive serum contain HIV RNA detectable by PCR after washing and cannot be used. As this is within the range of false positive results for this test, these may represent samples that test positive but contain no HIV.
Alternatively, the sperm may be contaminated with HIV from the seminal plasma or leukocytes during the steps of the sperm washing process. Contamination by leukocytes during sperm processing is believed to be the source of most of the HIV in the final sperm suspension (Nicopoullos et al., 2010). In addition to HIV associated with leukocytes, some virus particles are free in semen (Kiessling, 2005). Some of this HIV is sedimented to the lower gradient phase during centrifugation and may be a source of contamination, particularly if the gradient separation is not followed by a swim-up (Fiore et al., 2005). For confirmatory testing by PCR, the washed sperm sample can be stored at room temperature, at 4oC or cryopreserved while testing for HIV is carried out. The PCR technique can take up to 20 h, during which the processed sperm lose viability and motility, although newer kits can provide results in as little as 6 h. Cryopreservation allows for the PCR to be re-run if positive or negative controls fail on the day of testing (Bujan et al., 2007). Specimens found negative for HIV are then used for IUI or for IVF–ICSI. Insemination should not be carried out if HIV DNA or RNA is detected.
Quality control for PCR has not been consistently applied in programmes treating HIV-discordant couples. Although different methods of HIV RNA detection were used, assay sensitivity was 82% and specificity for detection of 500 copies RNA/million sperm was 95% (Pasquier et al., 2006). More recent assays such as the AMPLICOR HIV-1 MONITOR test, which detects HIV RNA has a sensitivity of 100% for the detection of 7.5 copies of HIV-1 RNA per reaction (400 copies/ml) and a specificity of 100% as validated by the supplier for testing of serum (Zamora et al., 2016).
In semen samples pre-loaded with known concentrations of HIV-1 virus, Fiore et al. (2005) found that neat semen samples containing 1000–50,000 copies viral RNA/ml had no virus detectable after the density gradient centrifugation step. In semen samples containing 10,000–500,000 copies viral RNA/ml, complete removal of the virus was observed only after the swim-up step after gradient. In semen samples containing 1–3 million copies of viral RNA/ml, persistence of viral RNA after two standard washing procedures was observed in some of the aliquots tested. These findings indicated to the investigators that the efficiency of sperm washing in removing HIV-1 varies according to the amount of virus present in the sample.
Use of microbicide
The microbicide, PPCM, has been investigated as a prophylactic during assisted reproduction techniques against HIV transmission. Adding PPCM to sperm washing medium reduced the viral titre of HIV-positive semen by 3–4 logs or 99.94% compared with 1–2 logs or 92% for washing alone under research laboratory conditions. This irreversible inhibition of HIV-1 had no adverse effect on sperm motility, forward progression or acrosome reaction (Anderson et al., 2011). The use of microbicides against transmission of HIV-1, however, has not completed phase III clinical trials for HIV prevention.
Pre-exposure prophylaxis (PrEP) with daily HAART has demonstrated clinical efficacy against HIV-1 acquisition (Andrews and Heneine, 2015) and is strongly recommended by the World Health Organization for non-HIV infected individuals at high risk of exposure (World Health Organization, 2015). Current federal guidance recommends that providers address the use of PrEP for couples attempting conception (Centers for Disease Control and Prevention et al., 2014).
Truvada, a combination tablet containing emtricitabine and tenofovir disoproxil fumarate, has been approved by the United States Food and Drug Administration to prevent infection in uninfected partners of HIV-positive men. Because Truvada must be taken daily, adherence to daily dosing is a limitation. Use of Truvada has been studied in high-risk populations, primarily in Africa. Several small have reported on the use of PrEP with sexual intercourse limited to the fertile period for HIV-discordant couples; however, little has been reported on the use of PrEP in the context of assisted reproduction techniques. This may prove to be a useful modality of risk reduction for serodiscordant couples, where the female partner can take Truvada while being inseminated by her HIV-positive partner's semen following special washing.
Double tube method
A method for limiting contamination of sperm during the gradient separation procedure is the double tube method (Loskutoff et al, 2005 and Politch et al, 2004). Recently, it was shown that men who were seropositive for HIV had semen samples decontaminated with density gradient followed by ProInsert (Nidacon) (Fourie et al., 2015). This product is a polypropylene tube insert that forms a double-tube system for sperm processing, allowing for retrieval of the sperm pellet at the bottom of the tube through a channel, which leads all the way down to the pellet without coming in contact with gradient material contaminated with leukocytes and free virus. With this protocol, there is reportedly no need for a swim-up step after density gradient.
Fourie et al. (2015), found that 54% of initial neat semen samples tested positive for HIV-1 DNA, RNA or both. Of 103 samples from 95 men, only two samples after processing were positive for HIV-1 DNA and none for RNA (Fourie et al., 2015). Semen processing using the double tube method followed by PCR validation of processed sperm samples may provide a safe method for reducing the time and processing stress, and increasing the number of purified sperm obtained, using the current gradient/swim-up method.
The current recommended treatment for HIV serodiscordant couples seeking pregnancy through assisted reprduction techniques in the USA is ICSI, despite compelling evidence of successful IUI treatment for years in Europe and other countries without any transmission to mother or baby. Use of ICSI is associated with risks and costs that can be minimized by the use of IUI for some couples, such as those with hepatitis B or hepatitis C. The risk–benefit analysis must consider both the higher cost and the higher success rate of IVF–ICSI compared with IUI. Significantly fewer cycles with the potential for contamination may be needed using IVF–ICSI. At all times, the goal of the laboratory is to reduce risk of viral transmission to staff and patients. A number of accommodations in laboratory protocol and workflow can be made to achieve risk reduction, which allows clinics to offer fertility treatment to those with chronic infectious disease.
The authors wish to thank Stanley Harris, Melanie Clemmer and Marlane Angle for their thoughtful review of state laws regarding use of HIV-positive sperm in assisted reproduction techniques.
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Dr Sangita K Jindal is an Associate Professor and the Laboratory Director of the IVF programme at Albert Einstein College of Medicine/Montefiore Medical Center, Bronx NY. Dr Jindal received her PhD in reproductive physiology at the University of Toronto. She has published over 40 peer-reviewed articles and book chapters. Dr Jindal is active on national committees within The American Society for Reproductive Medicine (ASRM), the Society for Assisted Reproductive Technologies (SART), and the Society for Reproductive Biologists and Technologists (SRBT), the affiliate society within ASRM representing all scientists and laboratorians in reproductive biology.
a Department Obstetrics, Gynecology and Women's Health, Albert Einstein College of Medicine, Montefiore's Institute for Reproductive Medicine and Health, 1300 Morris Park Avenue, Bronx, NY 10461, USA
b Department Obstetrics and Gynecology, Rush University Medical Center, 1653 West Congress Parkway, Chicago, IL 60612
c Male Fertility Lab, Department Urology, University of Washington, 4245 Roosevelt Way NE, Seattle, WA 98105
d Reproductive Medicine and Fertility, Department Obstetrics, Gynecology and Women's Health, University of Missouri, 500 N. Keene St, Suite 203, Columbia, MO 65201
* Corresponding author.
© 2016 Reproductive Healthcare Ltd., Published by Elsevier B.V.