Antiphospholipid antibodies and pregnancy rates and outcome in in vitro fertilization patients

The Impact of Emotional Responses on Female Reproduction: Fibrinolysis in the Spotlight

Fibrinolytic enzymes modify various substrates required for tissue remodeling, playing a crucial role in mechanisms underlying resilience, reward processing, ovulation, embryo implantation, and placentation. Individuals with low resilience and reduced reward responsiveness, when exposed to chronic stress, are at increased risk of experiencing a range of negative emotions. Chronic anxiety and melancholia are examples of negative emotions associated with hypercortisolism, while fear and atypical depression are characterized by systemic inflammation. Both cortisol and inflammatory cytokines stimulate the production of plasminogen activator inhibitor-1 (PAI-1), a potent fibrinolysis inhibitor. Chronic anxiety, fear, and depression are among the many hypofibrinolytic conditions increasing the risk of oligo-anovulation, miscarriage, fetal growth restriction, and preeclampsia. Although significant, the impact of negative emotions on implantation is not as obvious as on ovulation or placentation. Other hypofibrinolytic conditions that may affect female reproduction through mechanisms dependent or independent of PAI-1 include metabolic disturbances (e.g., due to consumption of highly palatable foods, often used to alleviate negative affect), inflammation, hyperhomocysteinemia, hypothyroidism, hypercortisolism, antiphospholipid antibodies, and the 4G allele of the PAI-1 gene. Benzodiazepines and antidepressants should be used with caution in the first trimester as this combination may cause malformations. Also, selective serotonin reuptake inhibitors have fibrinolytic properties that increase the risk of bleeding after surgical procedures. Psychological interventions, especially group therapy, are effective in the prevention of reproductive disorders. Controlled trials are needed to test the hypothesis that female reproductive health depends on psychological well-being, a balanced diet and physical activity, suppression of inflammation and autoantibodies, and homocysteine and hormonal homeostasis.

Serum antiphospholipid antibody status may not be associated with the pregnancy outcomes of patients undergoing in vitro fertilization

BACKGROUND

Antiphospholipid syndrome (APS) is an autoimmune disease that is associated with recurrent pregnancy loss. It is still controversial whether the presence of antiphospholipid antibodies (aPL) in the serum of patients with in vitro fertilization-embryo transfer (IVF-ET) has a negative effect on the outcomes. In view of the discrepancies, a meta-analysis of the published data was performed to explore the relationship of aPL and IVF-ET outcomes.

METHODS

We searched for all published articles indexed in PubMed, Web of Science, and Cochrane Library, which were retrieved up to April, 2021. A total of 921 studies were yielded, of which 6 finally met the inclusion criteria. We carried out the meta-analysis by pooling results of these studies with Review Manager 5.3 software. The effect index was measured with 95% confidence intervals (CIs) of the relative risks (RRs).

RESULTS

Six eligible studies were included in this meta-analysis, involving 3214 patients. Our results showed that positive aPL was not associated with decreased clinical pregnancy rate (RR 0.97; 95% CI 0.91-1.04). There was no correlation between positive aPL and increased miscarriage risk (RR 1.22; 95% CI 0.94-1.58). Only 5 of the 6 studies referred to live birth rate, but still no association was found between them (RR 0.95; 95% CI 0.81-1.11).

CONCLUSIONS

The results showed that the presence of positive aPL neither decreased clinical pregnancy rate and live birth rate, nor increased miscarriage rate in women undergoing IVF, which is differed from the opinion of clinical practice. More prospective studies with high quality and larger sample size are needed to evaluate the relationship between positive aPL and outcomes of IVF-ET.

Antiphospholipid syndrome and infertility

Antiphospholipid syndrome is a systemic autoimmune disease associated with obstetric complications along with vascular events affecting multiple organ systems in patients having positive titers of antiphospholipid antibodies. Eight to 20% of infertility cases have an unknown cause, part of which could be due to antiphospholipid syndrome. Although still debatable, many studies have addressed the relation between reproductive failure and antiphospholipid antibodies through the relation between antiphospholipid antibodies and unexplained infertility as well as the effect of antiphospholipid antibodies on the outcome of in vitro fertilization–embryo transfer. Few studies and cases have associated the presence of antiphospholipid antibodies with male infertility, describing morphofunctional penile abnormalities and testicular infarction. There are not enough data to support the routine practice of testing antiphospholipid antibodies in patients with infertility.

The hidden world of anti-phospholipid antibodies and female infertility: A literature appraisal

Even though the association of anti-phospholipid antibodies (aPL) with infertility is debated, infertile women are commonly screened for aPL. To review evidence, a systematic PubMed search was conducted to retrieve papers addressing (i) the association between aPL and infertility, (ii) the positivity rate of criteria and non-criteria aPL in women with infertility, (iii) the association between aPL and assisted reproduction technologies (ART) outcome, (iv) the efficacy of medical treatments on ART outcome, and (v) the effects of ART on thrombotic risk. A total of 46 papers were considered; several limitations emerged: (i) wide heterogeneity in study populations, (ii) non-prospective design in 90% of studies, and (iii) aPL cutoffs not conforming to international guidelines in more than 75% of studies; aPL positivity not confirmed in 89% of studies. Most studies evinced an association between infertility and anti-β2GPI antibodies and almost all non-criteria aPL. The association rate with infertility was below 50% for lupus anti-coagulant, anti-cardiolipin antibodies (aCL), and anti-phosphatidic acid antibodies. According to our estimates, overall positivity rates of criteria and non-criteria aPL tests are 6% and 3% among infertile women, 1% and 2% among controls, respectively. A significant difference in the positivity rate of patients versus controls emerged for aCL only. Five of 18 studies reported a detrimental effect of aPL on ART outcome. Only one of the six studies assessing the effects of treatment on ART outcome among aPL-positive infertile women reported a benefit. All relevant studies reported no increase in the rate of thrombosis among aPL-positive women undergoing ART.

Antiphospholipid antibodies and infertility

Since the late 1980s some publications have proposed that antiphospholipid antibodies (aPL) may have some relationship with infertility, considering reported deleterious effects that aPL exert on trophoblast proliferation and growth. Although not included in current classification criteria for antiphospholipid syndrome, many physicians investigate for aPL in patients with a history of infertility, including antibodies not listed in classification criteria, and most of those patients will receive anticoagulant therapy if any of those antibodies have a result considered positive. A review of literature was conducted searching for studies that investigated the association of aPL and infertility and if aPL positivity alters in vitro fertilization (IVF) outcome. The definition of infertility, routine work-up to exclude other causes of infertility, definition of IVF failure as inclusion criteria and control populations were heterogeneous among studies. Most of them enrolled women over 40 years of age, and exclusion of other confounding factors was also inconsistent. Of 29 studies that assessed aPL positivity rates in infertile women, the majority had small sample sizes, implying a lack of power, and 13 (44.8%) reported higher frequency of aPL in infertile patients compared to controls, but most of them investigated a panel of non-criteria aPL tests, whose clinical significance is highly controversial. Only two studies investigated all three criteria tests, and medium-high titer of anticardiolipin cut-off conforming to international guidelines was used in one study. Considering IVF outcome, there was also disparity in this definition: few studies assessed the live birth rate, others the implantation rate. Of 14 publications that addressed the relationship between aPL and IVF outcome, only two described a detrimental effect of these autoantibodies. In conclusion, available data do not support an association between aPL and infertility, and aPL positivity does not seem to influence IVF outcome. Well-designed clinical studies recruiting women with a clear diagnosis of infertility and a high-risk aPL profile should be performed to test whether clinically relevant aPL do-or not-exert an effect on human fertility.

Infertility and miscarriage: common pathways in manifestation and management

The relationship between miscarriage and fertility is complex. While most healthcare settings treat miscarriage as a problem of subfertility in assisted reproduction units, others believe that miscarriage occurs in super-fertile women. Infertile women undergoing assisted reproduction are at a greater risk of having a miscarriage especially at an advanced age compared with women conceiving naturally. Aberrant expression of immunological factors and chromosomal abnormalities underlie both infertility and miscarriage. Common risk factors include increased maternal age, obesity, smoking, alcohol, pre-existing medical conditions and anatomical abnormalities of the reproductive system. Management pathways of both conditions may be similar with pre-implantation genetic testing and assisted reproductive technology used in both conditions. This paper discusses the synergies and differences between the two conditions in terms of their epidemiology, etiopathogenesis, risk factors and management strategies. The two conditions are related as degrees of severity of reproductive failure with common pathways in manifestation and management.

14th International Congress on Antiphospholipid Antibodies Task Force report on obstetric antiphospholipid syndrome

Pregnancy morbidity is one of the clinical manifestations used for classification criteria of antiphospholipid syndrome (APS). During the 14th International Congress on Antiphospholipid Antibodies (aPL), a Task Force with internationally-known experts was created to carry out a critical appraisal of the literature available regarding the association of aPL with obstetric manifestations present in actual classification criteria (recurrent early miscarriage, fetal death, preeclampsia and placental insufficiency) and the quality of the evidence that treatment(s) provide benefit in terms of avoiding recurrent adverse obstetric outcomes. The association of infertility with aPL and the effectiveness of the treatment of patients with infertility and positive aPL was also investigated. This report presents current knowledge and limitations of published studies regarding pregnancy morbidity, infertility and aPL, identifying areas that need better investigative efforts and proposing how critical flaws could be avoided in future studies, as suggested by participants of the Task Force. Except for fetal death, there are limitations in the quality of the data supporting the association of aPL with obstetric complications included in the current APS classification criteria. Recommended treatments for all pregnancy morbidity associated to APS also lack well-designed studies to confirm its efficacy. APL does not seem to be associated with infertility and treatment does not improve the outcomes in infertile patients with aPL. In another section of the Task Force, Dr. Jane Salmon reviewed complement-mediated inflammation in reproductive failure in APS, considering new therapeutic targets to obstetric APS (Ob APS).

The correlation of autoantibodies and uNK cells in women with reproductive failure

There is conflicting evidence on the role of autoimmune disorders in reproductive failure, including recurrent miscarriage (RM) and recurrent implantation failure (RIF), after in vitro fertilisation (IVF). Several commonly studied autoimmune markers in women with reproductive failure include antiphospholipid antibodies (APAs), thyroid peroxidase antibodies (TPA) and uterine natural killer (uNK) cells. However, there have not been any studies that have examined the correlation of these markers in women with reproductive failure. To determine if women who tested positive for autoantibodies (APA and thyroid peroxidase antibodies) have significantly higher uNK cell numbers than women who tested negative for these antibodies, the percentage of stromal cells that stained positive for CD56 was identified by immunocytochemistry in endometrial biopsies from 42 women with unexplained RM (29 women tested negative for autoantibodies and 13 women tested positive for autoantibodies) and 40 women with unexplained RIF (30 women tested negative for autoantibodies and 10 women tested positive for autoantibodies). Biopsies were obtained on days LH+7 to LH+9. There was no significant difference in uNK cell numbers between women with unexplained RM who tested negative and those who tested positive for autoantibodies. Similarly, there was no significant difference in uNK cell numbers between women with unexplained RIF who tested negative and those who tested positive for autoantibodies. In women with reproductive failure the presence of autoantibodies does not appear to affect the numbers of uNK cells in the endometrium around the time of implantation.

Implantation Failure, Etiology, Diagnosis and Treatment

Embryonic implantation is a complex interaction between the embryo and the endometrium. Despite great investigative effort this process is still obscure. Contrary to the great advancement in patient care, follicular recruitment, oocyte quality and aspiration, embryo quality, culture and cryopreservation, our understanding of the implantation process did not enhance as much, and the tools to intervene within this process are limited. The implantation of the transferred embryos still remains the major limiting factor in IVF. Here we will review the current literature on the maternal (uterine, hematologic, immunologic and others) and embryonic factors that are associated with repeated implantation failure (RIF) and describe the various therapeutic approaches to cope with them. In addition, we will present our conclusive recommendations on how to investigate and manage RIF based on the literature and our own experience.

HEPARIN IN HUMAN PLACENTAL DEVELOPMENT AND THE PREVENTION OF PLACENTAL COMPLICATIONS OF PREGNANCY

The development of effective anticoagulant drugs available for use in pregnancy has resulted in dramatic improvements for a number of potentially life-threatening conditions. These include the treatment and prevention of venous thromboembolism and the thrombotic complications of antiphospholipid antibody syndrome, as well as the management of pregnant women with mechanical heart valves. The most commonly used class of drug includes heparin, a highly-charged macro-molecule that does not cross the placenta, in contrast to the potentially teratogenic and fetotoxic oral drug warfarin. This review will focus on our current lack of understanding of the wider actions of heparin and examines the possibility that large numbers of pregnant women are presently being treated inappropriately with heparin.

Anti-phospholipid antibodies do not affect IVF success

The assessment of anti-phospholipid antibodies (APA) is not indicated among couples undergoing IVF, and therapy is not justified on the basis of existing data.

Anticoagulant therapy and pregnancy

Low dose aspirin therapy is one of the anticoagulant treatments used during pregnancy. Anticoagulant agents may be useful for several disorders, such as recurrent miscarriage, pre-eclampsia, fetal growth restriction and infertility. However, it is unclear whether anticoagulant therapy can increase the live birth rate in all of these cases. Recent data suggest that a low-dose aspirin and heparin combination therapy is effective in the prevention of recurrent pregnancy loss in women with antiphospholipid syndrome. Thrombogenic diseases, for example, protein C deficiency, protein S deficiency, factor XII deficiency and hyperhomocysteinemia, may cause pregnancy loss. The etiology of recurrent miscarriage is often unclear and may be multifactorial, with much controversy regarding diagnosis and treatment. Although 70% of recurrent pregnancy losses are unexplained, anticoagulant therapy is effective in maintaining pregnancy without antiphospholipid antibody syndrome. We conclude that a low-dose aspirin and heparin combination therapy can be useful for unexplained cases of recurrent pregnancy loss without antiphospholipid antibody syndrome. (Reprod Med Biol 2008; 7: 1-10).

Influence of antiphospholipid antibodies on pregnancy outcome in women undergoing in vitro fertilization and embryo transfer

PROBLEM

Antiphospholipid antibodies (APA) are thought to be involved in recurrent pregnancy loss. Therefore, we investigated the impact of APA on pregnancy outcome in women undergoing in vitro fertilization and embryo transfer (IVF-ET).

METHOD OF STUDY

Blood samples taken from 54 Korean women referred for IVF were tested for the presence of APA, anticardiolipin antibody IgG and IgM and lupus anticoagulant. The standard gonadotropin-releasing hormone agonist long protocol was used for ovarian stimulation.

RESULTS

Nine patients (16.7%) were positive and 45 (83.3%) were negative for APA. There were no significant differences between the two groups in clinical characteristics such as age, infertility duration, and response to controlled ovarian hyperstimulation. However, pregnancy outcome significantly differed between the two groups (p < 0.05). The APA positive group and APA negative group had abortion rates of 62.5% and 20.0%, respectively and delivery rates of 37.5% and 80.0%, respectively.

CONCLUSION

The presence of APA in women undergoing IVF-ET was associated with a poor pregnancy outcome.

Low-dose aspirin for in vitro fertilization: a systematic review and meta-analysis

Despite recent advances in ovarian stimulation regimens and laboratory techniques, the pregnancy rate of assisted reproduction remains relatively low. New methods that would potentially improve implantation rates are needed. One proposed strategy involves enhancement of blood flow at the implantation site with the use of low-dose aspirin. We conducted a systematic review and meta-analysis to investigate the effect of low-dose aspirin on likelihood of pregnancy in women undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI). An electronic search of the literature was conducted targeting reports published over the last 26 years. Only randomized controlled trials (RCTs) comparing aspirin with placebo or no treatment in IVF/ICSI women were included in the meta-analysis. A number of relevant outcomes including pregnancy and live birth (LB) rates were investigated. Pooled relative risk (RR) and 95% confidence interval (CI) were calculated using a random-effects model. Inter-study heterogeneity among the trials was assessed using the Cochran's Q test. Ten RCTs were identified from the literature search, six of which met the criteria for inclusion in the meta-analysis. Clinical pregnancy (CP) rate per embryo transfer (ET) was not found to be significantly different between patients who received low-dose aspirin and those who received placebo or no treatment (RR 1.09, 95% CI 0.92-1.29). None of the other outcomes, including CP per cycle, spontaneous abortion or ectopic pregnancy per CP and LB rate per cycle or ET was found to differ significantly between the compared groups. On the basis of up-to-date evidence, low-dose aspirin has no substantial positive effect on likelihood of pregnancy and, therefore, it should not be routinely recommended for women undergoing IVF/ICSI.

Investigation and treatment of repeated implantation failure following IVF-ET

Pregnancy rate following one cycle of IVF and ET can be as high as 60%. But even in the very successful units, some couples fail repeatedly. The causes for repeated implantation failure (RIF) may be because of reduced endometrial receptivity, embryonic defects or multifactorial causes. Various uterine pathologies, such as thin endometrium, altered expression of adhesive molecules and immunological factors, may decrease endometrial receptivity, whereas genetic abnormalities of the male or female, sperm defects, embryonic aneuploidy or zona hardening are among the embryonic reasons for failure of implantation. Endometriosis and hydrosalpinges may adversely influence both. In this mini review, we discuss the suggested methods for evaluation and treatment of RIF: repeated hysteroscopy, myomectomy, endometrial stimulation, immunotherapy, preimplantation genetic screening (PGS), assisted hatching, zygote intra-Fallopian transfer (ZIFT), co-culture, blastocyst transfer, cytoplasmic transfer, tailoring stimulation protocols and salpingectomy for hydrosalpinges.

IgG-antiphospholipid antibodies in follicular fluid of IVF-ET patients are related to low fertilization rate of their oocytes

PROBLEM

Patients undergoing in vitro fertilization and embryo transfer (IVF-ET) failures show an increased incidence of antiphospholipid antibodies (aPL) in their blood. The physiological manifestations of aPL in this patient group are nonetheless controversial. Pathological effects of aPL on embryos in vitro have been documented. We questioned whether aPL if found in follicular fluids (FFs) could result in embryonic damage.

METHOD OF STUDY

Blood from 44 patients with three or more IVF-ET failures were tested by enzyme-linked immunosorbent assays (ELISA) for the presence of immunoglobulin (Ig)G, IgM and IgA aPL. Both the 29 aPL-positive and 15 aPL-negative patients gave permission for FF collection during their next IVF-ET attempt for additional aPL determinations.

RESULTS

Patients with no aPL in their blood, had no aPL in their FFs. Patients with IgG and/or IgM aPL in their blood had IgG but not IgM in their respective FFs.

CONCLUSIONS

The presence of IgG aPL in FFs and increased infertility length were significantly related to lower fertilization rates, independently. Follicular fluid IgG aPL appears as a risk factor in association with successful IVF-ET outcomes.

[Hormone therapy, fertility and pregnancy in antiphospholipid syndrome]

Antiphospholipid syndrome (APS) carries a risk of thrombosis and infertility. Consequently the use of any type of hormone therapy and pregnancy in APS requires special considerations. The present article provides a broad review of all these issues. The use of contraception, hormone replacement therapy and selective estrogen receptor modulators in APS are described. In vitro fertilization/embryo transfer and ovarian induction in these patients are reviewed. Lastly, the possible fetal and maternal complications that can occur during pregnancy are described and, based on the literature, recommendations for the management of pregnancy in women with APS are provided.

Antiphospholipid antibodies and coagulation defects in women with implantation failure after IVF and recurrent miscarriage

Evaluation of patients with IVF implantation failure or recurrent miscarriage often frustratingly fails to elicit any particular cause for their problem. Testing for antiphospholipid antibodies or thrombophilia is commonly carried out, and interpretation of results in the light of the current evidence is extremely difficult. This paper reviews the purported pathogenetic mechanisms and clinical associations between both antiphospholipid antibodies and inherited thrombophilias, and reproductive failure. The current management strategies are also critically evaluated and recommendations are made for optimal, evidence-based clinical practice.

Drug intervention in early pregnancy after assisted reproductive technology

Implantation in humans is a complex, closely regulated, highly selective and relatively poorly understood process. Humans have the highest rate of miscarriage in mammals and various pharmacological manipulations have been used to minimize pregnancy losses in both spontaneous pregnancies and pregnancies resulting from assisted reproduction technology. The widespread application of protocols using numerous drugs in assisted reproduction treatment has led to an increasing number of pregnancies exposed to these drugs. The vast majority of these protocols have been based on data from a few observational and often retrospective clinical studies. This paper reviews the recent literature on drug interventions in early pregnancy after assisted reproduction treatment. It is concluded that there are still numerous issues about the safety of most drugs for both the women and their fetus. In many cases, the benefits are theoretical and the possible long-term side-effects are untested. There is an urgent need for more epidemiological studies and randomized controlled trials to explore the use, efficacy and side-effects of both old and new drugs in early pregnancy after assisted reproduction treatment.

Impact of circulating free tumor cells in the peripheral blood of colorectal cancer patients during laparoscopic surgery

Despite widespread use of laparoscopic surgery for colorectal operations, its application for curative resection of colorectal cancer is still controversial. One of the major concerns is the impact of the laparoscopic procedure on dissemination of tumor cells. The main purpose of this study was to investigate the impact of laparoscopic surgery on circulating tumor cells in colorectal cancer patients. Quantitation of circulating free tumor cells (FTCs) was performed preoperatively, during the operation, and 14 days later by means of real-time quantitative reverse transcriptasepolymerase chain reaction (RT-PCR) targeting guanylyl cyclase C (GCC) mRNA in 42 colorectal cancer patients undergoing laparoscopic resections. Despite an increasing trend of FTC detection in patients with advancing stage, there is no significant difference in the preoperative FTC level by disease stage. No elevation in FTC level was found during the laparoscopic procedure in most patients compared with their preoperative FTC value. Patients with a persistently high FTC load [per nucleated blood cells (NBCs)] (> 10(2) FTCs/10(6) NBCs) 2 weeks postoperatively portends a poor prognosis regarding disease recurrence and tumor-related mortality when compared to those with an undetectable or low FTC load (< or = 10(2) FTCs/10(6) NBCs). We concluded that the laparoscopic procedure itself had no significantly deleterious effect on circulating FTCs and that the detection of FTCs by real-time qRT-PCR might be of clinical importance during the postoperative follow-up for colorectal cancer patients.

[So-called antiphospholipid antibodies and infertility: biological data]

Recurrent early and late foetal losses are common problems found in women with antiphospholipid syndrome, with therapeutic implication and improvement of the prognosis for the next pregnancies with antithrombotic therapy. After these results, some groups propose to extend the antiphospholipid investigations to infertility and failure of in vitro fertilization embryo transfer, but actually without demonstration of a real utility in the management of these women.

A randomized, double-blind, placebo-controlled trial of heparin and aspirin for women with in vitro fertilization implantation failure and antiphospholipid or antinuclear antibodies

OBJECTIVE

To investigate whether heparin and low-dose aspirin increase the pregnancy rate in antiphospholipid antibody or antinuclear antibody-seropositive women with IVF implantation failure.

DESIGN

A double-blind, randomized, transfer-by-transfer of fresh or cryopreserved embryos, crossover trial.A hospital infertility clinic and associated IVF service.

PATIENT(S)

Women seropositive for at least one antiphospholipid (APA), antinuclear (ANA), or beta(2) glycoprotein I autoantibody and >or=10 embryos transferred without achieving pregnancy (n = 143).

INTERVENTION(S)

Subcutaneous unfractionated heparin (5000 IU b.i.d.) and aspirin (100 mg daily) (158 transfers of 296 embryos) or placebo (142 transfers of 259 embryos) from the day of embryo transfer.

MAIN OUTCOME MEASURE(S)

Fetal heart per embryo transferred (implantation rate).

RESULT(S)

There was no significant difference in pregnancy rates or implantation rates between treated and placebo cycles; for example, fetal hearts per embryo transferred implantation rates were 6.8% (20/296) and 8.5% (22/259), respectively, and the generalized estimating equation covariate adjusted relative pregnancy rate was 0.65 (95% confidence interval, 0.33-1.28). The implantation rate for seropositive trial participants (42/555, 7.6%) compared favorably with that for IVF implantation-failure patients continuing treatment outside the trial (147/3237, 4.5%).

CONCLUSION(S)

Heparin and aspirin did not improve pregnancy or implantation rates for APA-positive or ANA-positive patients with IVF implantation failure.

Immune testing in fertility practice: truth or deception?

PURPOSE OF REVIEW

Much attention has been paid to the role of immunology in reproductive success or failure. Every step in the establishment of normal pregnancy has been implicated as a possible site of immune-mediated reproductive failure. The widespread testing of antiphospholipid, antinuclear, antithyroid, and antisperm antibodies, as well as generalized immune testing, have thus been employed to diagnose patients with otherwise unexplained infertility or recurrent pregnancy loss. Controversial data surrounding the widespread and variable use of immune testing in current fertility practice is reviewed to determine which tests are warranted based on sound scientific evidence. Because it is postulated that early miscarriage, when occult, could represent a failure of embryo implantation indistinguishable from unexplained infertility, this analysis of immune testing includes a discussion of patients with recurrent pregnancy loss.

RECENT FINDINGS

Despite the increased prevalence of abnormal immune testing associated with early reproductive failure, the most rigorous studies have not proven a cause and effect between these phenomena. There is wide variation and inconsistency regarding this association, depending upon which test(s) are employed, the study methodology used, and the patient population under study. The significance of selected immunological test abnormalities associated with early reproductive failure is uncertain.

SUMMARY

Great variability exists in identifying candidates for immune testing, determining which tests to order, interpreting the test results, and offering immunologic treatments. This review argues that the use of widespread immune testing in clinical practice can not be supported by existing data. The resulting therapies are similarly of unconfirmed benefit and may cause harm.

Antiphospholipid antibodies in implantation failures

PROBLEM

The amino phospholipids (PL), phosphatidylserine (PS) and phosphatidylethanolamine (PE) are distributed asymmetrically in the plasma membranes of eucaryotic cells. This arrangement involves active transport of PS and PE from the outer to inner membrane leaflet by an aminophospholipid translocase (flipase). Cell activation, injury and programmed cell death (apoptosis) cause collapse of the PS/PE asymmetry by activation of another enzyme system, scramblase. Unlike other cells, the developing trophoblast exteriorizes PS during its differentiation.

METHODS OF STUDY

An analysis of published and unpublished data.

RESULTS

The trophoblast is targeted by antiphospholipid antibodies (aPL), especially to PS (aPS). Cardiolipin is not present in the trophoblast plasma membrane, nonetheless, anticardiolipin (aCL) has been implicated in trophoblast pathology. The aPS and aCL are often crossreactive. Both animal and in vitro experimental models have shown monoclonal and polyclonal aPS and aCL to specifically destroy trophoblast, inhibit syncytium formation, halt human chorionic gonadatropin (hCG) production, and limit trophoblast invasion. Antibodies to PE (aPE) have not been well characterized, however, recent reports from several independent laboratories document that aPE are associated significantly with very early (embryonic) recurrent pregnancy loss (RPL). Umeda and coworkers have shown that during cytokinesis (late telophase) of Chinese hamster ovary (CHO) cells, formation of PE rafts in cleavage furrows is required for completion of cell division and formation of daughter cells. This raises the question whether aPE might interfere with implantation and cell division during embryogenesis.

CONCLUSIONS

A role for aPL in implantation failure and occult pregnancy loss constitutes the basis of this overview.

Antiphospholipid antibodies and infertility

Antiphospholipid antibodies (aPL) are an established cause of recurrent pregnancy loss. As defective embryonic implantation is a common link between unexplained infertility and recurrent miscarriage, interest has focused on the potential relationship between aPL and implantation failure after in vitro fertilization and embryo transfer (IVF-ET). This review critically examines the published data to determine whether women undergoing IVF-ET should be routinely screened for aPL. Although most studies have reported an increased prevalence of aPL among women undergoing IVF-ET, prospective studies examining the effect of aPL on the outcome of IVF-ET demonstrate that these antibodies do not significantly affect either the implantation or ongoing pregnancy rates. The increased prevalence of aPL among women with infertility is therefore likely to be part of a generalized autoimmune disturbance associated with infertility. Hence routine screening for aPL among women undergoing IVF-ET is not warranted and therapeutic interventions should be used only in well designed randomized controlled trials.

Immunological testing and treatment in reproduction: frequency assessment of practice patterns at assisted reproduction clinics in the USA and Australia

BACKGROUND

The roles that alloimmunity and autoimmunity may play in reproductive failure, including recurrent pregnancy loss and failed IVF, have not been clearly established. To help define practice patterns, we investigated what tests clinicians in the USA and Australia were offering, to which patients (diagnostic groups) the tests were recommended, and in what situations immunological/anticoagulation treatment was advised.

METHODS

A five section survey was completed by senior physicians attending the annual national fertility society meetings in the USA and Australia. Results were tabulated and analysed.

RESULTS

Antiphospholipid antibody testing was offered to patients with recurrent pregnancy loss by almost all physicians surveyed. Patients with previous failure of IVF were tested much less often. Other immune tests (embryotoxic assay, natural killer cells and leukocyte antibodies) were ordered by none of the Australian participants and approximately 25% of the American participants. The use of immunotherapy and anticoagulation therapy for patients who tested positive for various immunological tests was also evaluated for frequency of use and reported secondary complications.

CONCLUSIONS

Large, well-structured studies examining the benefits of immunological evaluation and treatment are necessary before definite recommendations can be made.

Antiphospholipid syndrome and recurrent miscarriages

Sixty percent of recurrent spontaneous abortions are unexplained. Antiphospholipid syndrome is a multisystem disease with the predominant features of venous and arterial thrombosis, recurrent pregnancy loss, foetal death and the presence of antiphospholipid antibodies. Many epidemiological studies focus on antiphospholipid autoantibodies syndrome (APS) as a cause of recurrent spontaneous abortion (RSA). It is found that 7-25% of RSA would have APS as the main risk factor. 'Association not being synonymous with cause', the proportion of abortions due to the APS is difficult to estimate for several reasons: definition of recurrent abortion is variable, the assays for antiphospholipid antibodies are not well standardised, inclusion of patients in the study group according to the antibodies titre is author dependent. Recent studies suggest association of antiphospholipid antibodies syndrome not only with recurrent abortions but also with infertility. New mechanisms are described by which antiphospholipid antibodies could cause placental thrombosis and infarction, acting directly on the surface anticoagulant expressed on trophoblastic cells. Only lupus anticoagulant (LA) and anticardiolipin antibodies (aCL) assays are sufficiently standardised to be usable in routine. Testing for other antiphospholipid antibodies (aPLs) should remain investigational. Several treatments have been proposed: low doses of aspirin, low or immunosuppressive doses of corticosteroids, and preventive or effective dose of heparin, intravenous immunoglobulin.

Antibodies to phosphatidylethanolamine and phosphatidylserine are associated with increased natural killer cell activity in non-male factor infertility patients

Antiphospholipid antibodies (APA) have been identified in patients with recurrent pregnancy loss and IVF failure. Of these, antiphosphatidylethanolamine (aPE) and antiphosphatidylserine (aPS) may have special significance. A link between increased natural killer cell activity (NKa+) and trophoblast cell apoptosis has also been reported. This study was undertaken to determine how the APA profile was associated with peripheral NK cell activity. We evaluated 197 female IVF candidates for APA and NKa. Eighty-nine patients (45%) were APA+ and of these, 51 (57%) were aPE/aPS+. Fifty-four patients (27%) had increased NK cell activity. Some 51% of APA+ and 78% of aPE/aPS+ patients had increased NK cell activity compared with 8% and 13% when APA and aPE/aPS tested negative respectively (P: < 0.0001). Non-male factor infertility patients were APA+ and NKa+ in 57% and 34% of cases respectively, compared with 19% and 13% if a pure male factor was present. Some 88% of aPE/aPS+, non-male factor patients had increased NK cell activity, compared with 12% who tested aPE/aPS negative (P: < 0.0001) and 25% of aPE/aPS+, isolated male factor patients (P: < 0.0001). These findings establish a direct relationship between APA (specifically aPE/aPS) and increased peripheral NK cell activity among non-male factor infertility patients. It is possible that APA do not directly cause reproductive failure but rather function as markers or intermediaries for an underlying, abnormal activation of cellular immunity.

Pregnancy outcome is not affected by antiphospholipid antibody status in women referred for in vitro fertilization

OBJECTIVE

To determine the prevalence of antiphospholipid (aPL) and anti-beta 2 glycoprotein I (anti-beta2-GPI) antibodies in women referred for IVF and to prospectively evaluate the effect of these antibodies on IVF outcome.

DESIGN

Prospective observational study.

SETTING

A university hospital and IVF unit.

PATIENT(S)

Three hundred eighty consecutive women referred for IVF.

INTERVENTION(S)

Blood samples taken before commencement of IVF cycles were tested for the presence of aPL (lupus anticoagulant [LA], anticardiolipin [aCL], and antiphosphatidyl serine antibodies [aPS]) and anti-beta2-GPI antibodies.

MAIN OUTCOME MEASURE(S)

Antibody prevalence, pregnancy rates, and live birth rates.

RESULT(S)

Of the total 380 women, 89 tested persistently positive for aPL (23.4%). None of 176 women tested for IgG aPS antibodies had a positive titer. Only 3.3% (11 of 329) tested positive for anti-beta2-GPI antibodies. Pregnancy rate, live birth rate, gestational age at delivery, and birth weight were not affected by aPL status.

CONCLUSION(S)

Although women referred for IVF have a high prevalence of aPL, these antibodies do not affect the outcome of treatment. Screening women undergoing IVF for aPL is not justified.

Antiphospholipid antibodies and in vitro fertilization success: a meta-analysis

OBJECTIVE

To evaluate whether the presence of antiphospholipid antibodies among women undergoing IVF affects the likelihood of IVF success.

DESIGN

A meta-analysis of seven eligible studies on antiphospholipid antibodies and IVF outcome.

MAIN OUTCOME MEASURE(S)

Odds ratios (ORs) and 95% confidence intervals (CIs) of an association between the presence of antiphospholipid antibodies and both clinical pregnancy and live birth from IVF.

RESULT(S)

There was no significant association between antiphospholipid abnormalities and either clinical pregnancy (OR 0.99; 95% CI 0.64-1.53) or live birth (OR 1.07; 95% CI 0.66-1.75) in IVF patients.

CONCLUSION(S)

The measurement of antiphospholipid antibodies is not warranted in patients undergoing IVF.

Immunodiagnostic evaluation in women with reproductive failure

PROBLEM

Several immunological factors have been associated with diagnostic subpopulations of reproductive failure. It is important to determine a trend of immunological abnormalities among these subpopulations. The purpose of this study is to assist in the selection of treatment for patients suspected of having specific diagnoses of reproductive failure.

METHOD OF STUDY

Blood samples from 591 patients were evaluated for the presence of antiphospholipid (APA), antinuclear (ANA), and antithyroid (ATA) antibodies, as well as for lupus anticoagulant (LA), embryotoxic factors (ETF), and elevated levels of natural killer (NK) (CD56+) cells, and all tests were performed as a panel. The patients were grouped into the following diagnostic categories: recurrent pregnancy loss (n = 302), IVF/ET failure (IVFf, n = 122), unexplained infertility (n = 97), ovarian dysfunction (n = 47), and endometriosis (n = 23). The thresholds for positivity and the prevalence of the tested factors among normal healthy populations have been established by testing 100 or more healthy male and female individuals with each one of the tests used (general population control). All tests as panel were performed on 20 normal fertile female individuals as controls (fertile female controls).

RESULTS

Of all patients with reproductive failure, 75.6% had at least one abnormal test. The most frequent abnormal result was found to be the elevation of NK (CD56+) cells (37%), followed by ANA (34%), APA (24%), ATA (19%), and ETF (11%). Of the recurrent pregnancy loss patients, 74.2% had at least one positive abnormal result from all of the tests performed: overall, 70% of women with IVF failure had at least one abnormal test; of patients diagnosed with unexplained infertility, approximately 81% had at least one abnormal result; 74.4% of the patients with ovarian dysfunction and 52% of the patients with endometriosis had at least one abnormal result. From normal fertile controls, 10% showed at least one abnormal test result.

CONCLUSION

APA, ANA, ATA, ETF, and elevated NK (CD56 ) cells are significantly more prevalent among women experiencing reproductive failure than among the control group and normal healthy individuals.