Antiphospholipid antibodies and infertility: fact or fallacy

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.

[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.

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.

Antiphosphatidylserine antibodies are elevated in normal tension glaucoma

The two main entities of open-angle glaucoma are primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG). Both diseases may be associated with autoimmune processes. Therefore, IgG and IgM antibodies to phospholipids (APL) and their subspecies cardiolipin (ACL), phosphatidylserine (APS) and beta2-glycoprotein (beta2GP) were determined in 43 NTG patients, 40 POAG patients and 40 healthy controls in a prospective study. The most prominent observation was the increase in APS concentrations in NTG patients (IgG 20.6 +/- 2.7 U/ml, IgM 24.4 +/- 3.4 U/ml) compared with POAG patients (IgG 8.8 +/- 1.2 U/ml, IgM 11.0 +/- 1.7), and controls (IgG 7.7 +/- 1.3 U/ml, IgM 12.8 +/- 1.5 U/ml). APS may be important due to their binding specificity to phosphatidylserine molecules which become accessible during apoptosis; this in turn may lead to local thrombosis.

A literature review on the antiphospholipid syndrome and the effect on childbearing

OBJECTIVE

to review the literature on antiphospholipid antibodies and their significance to midwifery practice.

METHOD

databases using the keywords anticardiolipin antibodies, antiphospholipid antibodies, lupus antibodies, antiphospholipid syndrome, systemic lupus erythematosis, pregnancy loss, pre-eclampsia were searched, 548 articles were generated and 52 were used in the review.

FINDINGS

anticardiolipin antibodies are detrimental to successful pregnancy being implicated in failure of implantation, loss of the embryo and the fetus. There is also a risk of prematurity, intrauterine growth retardation and neonatal embolism. The risks to the mother are of pre-eclampsia and embolic complications. If diagnosed and treated early in pregnancy with low-dose aspirin and subcutaneous heparin the outlook for a successful pregnancy is much improved.

KEY CONCLUSIONS

much research remains to be undertaken. Researchers need to standardise their criteria so that findings are comparable and larger sample groups are necessary.

IMPLICATIONS FOR PRACTICE

antiphospholipid syndrome is an important disorder and a preventable cause of pregnancy loss. Midwives need to encourage women to persevere with therapy to preserve pregnancy and maybe prevent pre-eclampsia or thrombosis. When pregnancies are lost one of the hardest things is when the parents cannot understand why. Midwives need to understand the syndrome to collaborate with doctors in explaining it and supporting grieving parents.

Antiphospholipid (Hughes) syndrome in systemic lupus erythematosus

APS is found in 20% to 35% of patients with SLE. PAPS and secondary APS have similar features and aPL specificities. The clinical course of the secondary syndrome is independent of the activity and severity of lupus, but the presence of APS worsens the prognosis of patients with lupus. Some features of SLE may result from thrombosis in patients with APS; thus, these patients require anticoagulation rather than corticosteroids. Novel preliminary classification criteria for APS were formulated during a postconference workshop held in Sapporo, Japan, following the Eight International Symposium on Antiphospholipid Antibodies. Treatment of APS remains empirical because of limited controlled prospective data. There is strong evidence that patients with aPL-associated thrombosis are subject to recurrences and require prophylactic therapy. APS is a treatable cause of recurrent fetal loss in women with SLE. The treatment of choice is anticoagulation with heparin, either standard unfractionated heparin or LMWH. One of the main reasons for the improving outcomes in APS pregnancies is closer obstetric surveillance.

The anti-phospholipid antibody syndrome (Hughes syndrome): therapeutic aspects

Despite the enormous amount of work focused on the pathogenesis and clinical manifestations of the Hughes or anti-phospholipid syndrome (APS), there is little published on management. Usually, the diagnosis of APS is made after the first thrombotic event, when a thrombophilia screen is performed. These patients have a high risk of recurrent thromboses and current therapy centres on the use of thromboprophylaxis with warfarin. However, a number of clinical questions keep recurring: do arterial and venous thrombosis require the same intensity of anti-coagulation? When should warfarin be stopped? Should patients who develop thrombosis when other risk factors (oral contraceptive pill, prolonged resting etc.) are present be treated like those without any risk factors but the presence of anti-phospholipid antibodies (aPL)? How to manage a patient with recurrent thrombosis despite a high intensity anti-coagulation (International normalized ratio (INR) between 3.0-4.0)? Since many of the patients with aPL are fertile women, a substantial group of patients are diagnosed after recurrent pregnancy loss. Low-dose aspirin for those patients without previous thrombosis and aspirin plus heparin for patients with a history of thrombotic events are the current therapeutic options. However, some questions remain unanswered: does the addition of heparin to low-dose aspirin in women with first trimester recurrent miscarriage but without previous thrombosis improve foetal outcome over and above aspirin alone? Which is the best therapeutic regime during pregnancy for patients with aPL-associated stroke? When should high-dose intravenous gammaglobulin be considered? Finally, very little is known about the risk of thrombosis in individuals positive for aPL but still free of thrombosis. Should these individuals receive any treatment? If so, which one? In this review we attempt to address some of these questions taking into account available data from retrospective and prospective studies and our own clinical experience.

Human reproductive failure is not a clinical feature associated with beta(2) glycoprotein-I antibodies in anticardiolipin and lupus anticoagulant seronegative patients (the antiphospholipid/cofactor syndrome)

It has been suggested that patients with clinical features suggestive of antiphospholipid syndrome but being lupus anticoagulant (LA) and anticardiolipin (aCL) negative, should be tested for antibodies to beta(2) glycoprotein-I (abeta(2)GP-I), a protein involved in the binding of antiphospholipid antibodies (aPL) to phospholipid surfaces. This was investigated in the present study where a total of 385 women aged </=40 years were included. Of these, 175 were experimental subjects and 210 were controls. The former comprised the following two study groups: 100 spontaneous recurrent aborters (group one), and 75 patients with repeated failure of embryo transfer (group two). Controls included three groups of women: 100 normal healthy parous women with no previous abortion (group three), 60 infertile patients achieving a live birth with their first in-vitro fertilization (IVF)/embryo transfer attempt (group four), and 50 patients with recurrent abortion who tested positive for aPL (LA and/or aCL) (positive controls, group five). Only one patient among recurrent aborters (group one) tested positive for abeta(2)GP-I. All women in groups two, three and four were negative for abeta(2)GP-I screening. As expected, prevalence of patients testing positive for abeta(2)GP-I was significantly higher in group five than among the other groups of patients (P < 0.001). No differences were observed regarding the prevalence of abeta(2)GP-I positive sera in the subgroup of patients having aCL and those having the LA in group five. It is concluded that abeta(2)GP-I screening in first-trimester recurrent abortion or in failure of implantation after IVF is not warranted in patients without aPL as detected by standard antiphospholipid assays.