Hum. Reprod. Advance Access originally published online on October 27, 2005
Human Reproduction 2006 21(3):728-734; doi:10.1093/humrep/dei369
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Antiphospholipid antibodies in serum and follicular fluid—is there a correlation with IVF implantation failure?
1 Department of Obstetrics and Gynaecology, University of Auckland, Private Bag 92019, Auckland 1001, 2 Fertility Plus, Greenlane Clinical Centre, Private Bag 92189, Auckland 1003 and 3 Reproductive Technologies Group, AgResearch Limited, Ruakura Research Centre, Private Bag 3123, Hamilton 2001, New Zealand
4 To whom correspondence should be addressed. E-mail: karen{at}onlinecom.co.nz
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Abstract |
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BACKGROUND: Antiphospholipid antibodies (aPLs) are associated with infertility, but the mechanism underlying this statistical association is currently obscure. We aimed to investigate the finding that aPLs are concentrated in follicular fluid and to establish if this is associated with a poorer outcome from IVF. METHODS AND RESULTS: In 19.2% of 99 women undergoing IVF, at least one aPL was detected in their serum and/or follicular fluids, but the antibody levels in follicular fluid were not higher than in serum. Women with aPLs had a lower implantation rate (14%) than women without these antibodies (24.1%), but this difference was not significant (P = 0.127). There was also a non-significant reduction in the live birth rate for women with aPLs. In a parallel investigation, 10 sheep immunized with
2 glycoprotein I (2GPI) or irrelevant control antigens showed strong immune responses, but there were no significant differences between the levels of antibodies in the follicular fluid or serum from 2GPI or control immunized sheep. CONCLUSION: aPLs do not appear to be selectively concentrated in follicular fluids and, when present, do not adversely affect the reproductive outcome of women undergoing IVF.
Key words:
anticardiolipin/antiphosphatidylserine/antiphospholipid antibodies/2 glycoprotein I/IVF
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Introduction |
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Antiphospholipid antibodies (aPLs) are a group of autoantibodies associated with poor obstetric outcomes such as recurrent pregnancy loss, stillbirth, fetal growth restriction and pre-eclampsia, as well as thrombosis, thrombocytopenia and other autoimmune disorders (Chamley, 2002
). More recently, attention has focused on their possible association with infertility and IVF implantation failure. It has been shown that women undergoing IVF have an increased incidence of aPLs (Birkenfeld et al., 1994; Birdsall et al., 1996; Kutteh et al., 1997; Stern et al., 1998).
The mechanism by which aPLs induce fetal demise or thrombosis is currently unknown, but most aPLs are now known to bind to a complex antigen consisting of a negatively charged phospholipid, such as phosphatidylserine (PS) or cardiolipin (CL), and a lipid-binding protein (Kutteh et al., 1997; Chamley, 2002). The most studied of these lipid-binding proteins is 2 glycoprotein I (2GPI) (Chamley, 2002). Older studies suggested that aPLs may induce thrombosis of the uterine spiral arteries leading to fetal demise, but more recent studies suggest that other mechanisms, such as the direct disruption of placental trophoblast functions, are more likely to explain how aPLs adversely affect pregnancies (De Wolf et al., 1982; Di Simone et al., 1995, 2002, 2005; Chamley et al., 1998). It is difficult however, to envisage how aPLs in the maternal blood could prevent the implantation of an apparently healthy embryo conceived in vitro. A small study has suggested a mechanism whereby aPLs may be selectively concentrated in follicular fluid (el-Roeiy et al., 1987) from where the antibodies could potentially bind to the oocyte. Other studies have shown that aPLs may bind to oocytes and embryos and arrest embryo development, usually at the 
16 cell stage (Sthoeger et al., 1993; Kaider et al., 1999). As many IVF programmes return human embryos to the uterus at the 4- to 8-cell stage, developmental arrest at a later stage would present clinically as an IVF implantation failure. This may therefore be a mechanism by which aPLs cause IVF implantation failure.
The aims of this study were to determine if aPLs are selectively concentrated in follicular fluid and to establish if aPLs in the follicular fluid are associated with a poorer IVF outcome.
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Materials and methods |
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This study was approved by the Auckland Health and Disability Ethics Committee and by the Ruakura Animal Ethics Committee of AgResearch, Hamilton.
All women undergoing IVF treatment at Fertility Plus, National Women’s Hospital, Auckland were eligible for entry. Informed consent was obtained from all participants prior to oocyte retrieval.
Both serum and follicular fluid samples were collected on the day of oocyte retrieval. After examination for oocytes, follicular fluids were only stored if they appeared uncontaminated with blood as judged by microscopic examination. Samples were not analysed until all specimens had been collected. Demographic details and reproductive history data were collected retrospectively from the patient notes along with details of the index IVF cycle.
Patient characteristics
A total of 112 women were recruited between June 2002 and July 2003. Ninety-nine women were included in the final analysis, 13 being excluded because the follicular fluids obtained were too heavily bloodstained for accurate analysis. The characteristics of these women are summarized in Table I. Only one woman had a known autoimmune disease (rheumatoid arthritis) at the time of her treatment. She was found to be aPL negative and did not conceive with the first embryo transfer.
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IVF regimen
The majority of women (88, 88.9%) underwent a ‘long’ protocol of GnRH agonist-induced pituitary downregulation followed by ovulation induction. In 11 women (11.1%), GnRH agonists were used in a ‘flare’ or ‘short course’ ovulation induction regime. As per the protocol at Fertility Plus, all women commenced 100 mg aspirin (Cartia, GlaxoSmithKline, Auckland, New Zealand) daily from the start of GnRH agonist (Suprefact, Aventis, Auckland, New Zealand) administration until oocyte retrieval.
The dosage of gonadotrophin stimulation with recombinant FSH (Puregon, Pharmaco, Auckland, New Zealand or Gonal F, Douglas Pharmaceuticals Ltd, Auckland, New Zealand) was individualized [based on the woman’s age, body mass index (BMI), basal FSH results and previous response to treatment when applicable]. Estradiol (E2) levels and transvaginal scans were used to monitor ovarian response. Ovulation was triggered with 10 000 IU of HCG (Profasi, Douglas Pharmaceuticals Ltd) when 3 follicles reached 17 mm in diameter. Oocyte retrieval was carried out 35–36 h later and was generally performed transvaginally under i.v. sedation.
Fifty-nine women (59.6%) underwent routine IVF, 35 women (35.4%) required ICSI and in three women (3.0%) a combination of the two procedures was performed. Fertilization was determined by the presence of two adjacent pronuclei 16–18 h later. Embryos were maintained in culture and transferred to the uterus transcervically under ultrasound guidance using a Sydney IVF transfer catheter, 48–72 h after oocyte retrieval. A maximum of three embryos were transferred (mean two embryos) at one time. Any remaining good quality embryos were cryopreserved for subsequent use.
Luteal support was provided by HCG injection for women with E2 levels <10 000 pmol/l on the day of trigger, or progesterone pessaries (Uterogestan, Health Support Ltd, Auckland, New Zealand) for high responders (E2 >10 000 pmol/l). A serum -HCG pregnancy test was performed 14–16 days after transfer and repeated 2 and 7 days later if positive. Women with a positive pregnancy test had a transvaginal scan at 
7–8 weeks gestation to detect a clinical pregnancy, i.e. fetal heart activity. Outcomes of interest were the ‘implantation rate’ (gestation sac per embryo transferred), ‘total pregnancy rate’ (including biochemical, non-viable and ectopic pregnancies) and the ‘ongoing pregnancy/live birth rate’.
The outcome of the first embryo replacement (whether fresh or frozen) was correlated with the antibody status of the woman. Fresh embryo transfers occurred in 87 women (87.9%). Six women (6.1%) had a ‘freeze all’, whereby all the embryos were cryopreserved, as the women were considered to be at high risk of developing ovarian hyperstimulation syndrome (OHSS). A further six women did not proceed to embryo replacement; in two women, no oocytes were obtained at retrieval, whilst one woman had no successful fertilization after IVF. Another woman had only a single oocyte retrieved at pick-up and this was not suitable for ICSI. One woman did not have a fresh embryo transfer as she was symptomatic for OHSS and unfortunately no embryos were suitable for cryopreservation when assessed several days later. Another woman had embryos cryopreserved but embryo transfer was deferred until treatment for multiple fibroids was completed. Those women who did not have an embryo replacement were all aPL negative.
Immunization of sheep
Ten 2-year-old Coopworth ewes were used in an immunization study. Five ewes were immunized with purified human 2GPI, while five ewes were immunized with other antigens as positive controls. Two of the control ewes were immunized with purified human pre-B cell-enhancing factor (PBEF), two ewes were immunized with recombinant human indoleamine 2,3 dioxygenase (IDO) and a final ewe was immunized with keyhole limpet haemocyanin (KLH). The antigens were all prepared by emulsifying the relevant protein with Freund’s adjuvant. The animals were immunized with 50 µg of antigen on five occasions, each one approximately a month apart. The initial immunization employed Freund’s complete adjuvant but all subsequent immunizations employed Freund’s incomplete adjuvant. One month before the last immunization, a peripheral blood sample was obtained from the jugular vein and the serum analysed by enzyme-linked immunosorbent assay (ELISA) to confirm that an immune response had occurred. The estrous cycles of the ewes were then synchronized 1 week after the last booster immunization using CIDR type G intravaginal devices (DEC International, SVS Veterinary Supplies Ltd, Hamilton, New Zealand). Thirteen days later, the animals were administered gonadotrophin to stimulate the development of multiple follicles (Folligon 2000 IU, Intervet Ltd, SVS Veterinary Supplies Ltd). The animals were anaesthetized using 2% halothane and the ovaries removed by laparotomy. The follicular fluid was aspirated using a 19 gauge needle and syringe, and cellular debris was removed by centrifugation. The titres of antibodies in each sample were determined by incubating a 10-fold dilution series of serum or follicular fluid in ELISAs using the relevant antigen. Samples were then reanalysed in duplicate on two occasions at a dilution of 1:100 and the optical density at 490 nm determined using a Biorad Benchmark ELISA plate reader (Biorad, Auckland, New Zealand).
aPL ELISA
Serum and follicular fluid samples were analysed for both immunoglobulin (Ig) G and IgM antibodies against 2GPI, CL and PS using ELISA techniques as previously published (Stern et al., 1998).
The phospholipids PS and CL were obtained from Sigma (Sydney, Australia). Antibody screening was conducted as previously published (Johns et al., 1994). Briefly, the relevant phospholipid was diluted to 50 µg/ml in ethanol and 50 µl was coated onto the wells of 96-well ELISA plates by evaporation at 4°C overnight. Plates were blocked by the addition of 10% newborn calf serum in phosphate-buffered saline (PBS), pH 7.4, for 1 h at room temperature. The blocking solution was discarded and the plates washed three times with PBS, pH 7.4. Serum samples, diluted 1:100 in blocking solution, were then incubated on the plates for 1 h at room temperature. The plates were then washed three times with PBS, pH 7.4, and horseradish peroxidase (HRP)-conjugated goat anti-human 
-chain or µ-chain antiserum (Jackson Laboratories, ALS, Auckland, New Zealand), diluted 1:8500 in blocking solution, was added for 1 h at room temperature. The plates were again washed three times with PBS, pH 7.4, and the assay developed by addition of 1 mg/ml o-phenylamine diamine dihydrochloride (Sigma) in 0.1 mol/l citrate buffer, pH 5.5, containing 0.005% fresh H2O2. The reaction was stopped by the addition of 10% HCl and the optical density at 490 nm was determined using a Biorad Benchmark ELISA plate reader. Multiples of the median were used to estimate the 95th and 99th percentiles. Samples were considered to be positive when the optical density of a sample exceeded the 99th percentile of 292 normal serum samples (188 males and 104 fertile females) (Stern et al., 1998).
Where follicular fluid samples were available from more than one follicle, the average value of antibody levels was used for statistical analysis.
Protein ELISA
The 96-well ELISA plates were coated overnight at 4°C with 50 µl of purified 2GPI, IDO, PBEF or KLH (10 µg/ml in 0.1 mol/l carbonate, pH 9.0). The antigen solution was discarded and plates were blocked with 5% non-fat milk powder dissolved in PBS, containing 0.05% Tween 20 (PBST), pH 7.4, for 1 h at room temperature. The plates were washed three times with PBST before serum or follicular fluid samples, diluted in the blocking solution, were added for 1 h at room temperature. Plates were washed again three times with PBST and incubated for 1 h with HRP-conjugated goat anti-human -chain or µ-chain antiserum (Jackson Laboratories) diluted 1:8500 or with HRP-conjugated rabbit anti-goat IgG (Jackson Laboratories) in blocking solution. Finally, the plates were again washed three times with PBST and developed by addition of 1 mg/ml o-phenylamine diamine dihydrochloride (Sigma) in 0.1 mol/l citrate buffer, pH 5.5, containing 0.005% fresh H2O2. The reaction was stopped by the addition of 10% HCl and the optical density at 490 nm determined using a Biorad Benchmark ELISA plate reader.
For the human serum and follicular fluid samples, levels of anti-2GPI antibodies >99th percentile were considered elevated, as described above. For the analysis of sheep serum and follicular fluids, antibody titres were estimated by determining the dilution of sample that produced an optical density value above background.
Statistical analysis
For the human studies, statistical analyses were performed using SPSS Version 12.0 (SPSS New Zealand, Auckland, New Zealand) and Epi-Info 2002 (Centers for Disease Control and Prevention, Atlanta, USA). Numbers are presented as counts (percentages) for dichotomous data; continuous data are presented as either median (interquartile range) or mean (SD). Normally distributed continuous data were compared using the Student’s t-test. Frequency data were compared using the 
2 or Fisher’s exact test. A P-value of <0.05 was regarded as significant.
For the sheep study, differences in the levels of antibodies in serum and follicular fluids were examined by analysis of variance.
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Results |
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Of the 99 women analysed, 19 (19.2%) had at least one aPL demonstrated in their serum and/or follicular fluids. The most prevalent antibody found was
2GPI IgG, being present in 16 women. 2GPI IgM antibodies were demonstrated in four women. Four women had IgG antibodies and two women had IgM antibodies to CL. PS IgG antibodies were present in five women and no women demonstrated significant levels of IgM antibodies in either serum or follicular fluid (Figure 1). No women had IgM antibodies of any type tested found in their follicular fluid. Only two of the 19 women with antibodies had more than one type of antibody present in either their follicular fluid or serum.
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Of the aPL-positive women, 11 (57.9%) had antibodies found in their serum only, while the remaining eight (42.1%) women had antibodies in both serum and follicular fluid. In general, antibody concentrations in the follicular fluid were the same or lower than the serum concentrations. In only one woman was there any indication of selective concentration of aPLs in the follicular fluid. The level of anti-2GPI IgG in the follicular fluid from this woman was above the 95th percentile while her serum levels of anti-2GPI were less than the 95th percentile. However, in addition, this woman had elevated levels of IgM 2GPI (>99th), anti-CL (>95th) and anti-PS (>95th) antibodies in her serum. She did not conceive in the index cycle in which two embryos were transferred. A further three embryos were cryopreserved but did not survive thawing. Apart from this one woman, aPLs were not demonstrated to be selectively concentrated in follicular fluid.
The outcome of the first embryo replacement (whether fresh or frozen) was compared with the antibody status of the woman. Women who were aPL positive had a lower implantation rate (14%), in comparison with their aPL-negative counterparts (24.1%); however, this difference was not statistically significant (P = 0.127). Similarly, total pregnancy rates and ongoing pregnancy/live birth rates were lower in aPL-positive women than aPL-negative women, but this difference was also not significant (Table II). There were no differences in the women’s characteristics such as age, BMI, basal FSH level, duration or cause of infertility, number of oocytes retrieved and fertilization rates to account for the differences between groups (Table I). Similarly, the fertility outcomes of aPL-positive women when broken down and related to antibody class (IgG or IgM) or antigen specificity showed no significant differences in either the total pregnancy rate or ongoing pregnancy/live birth rates; however, the numbers analysed at this level were small (Table III).
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The data collected were also analysed using >95th percentile as a definition of antibody ‘positivity’. While the prevalence of aPL-positive women was increased to 55.6% in this analysis, the overall results were similar to those presented above. Total pregnancy rates were 40.9% in aPL-negative women, compared with 30.9% in aPL-positive women (P = 0.301). Ongoing pregnancy/live birth rates were 29.5 and 16.4%, respectively, in the two groups (P = 0.117).
Antibody levels in the follicular fluids of sheep
All of the sheep immunized with 2GPI or the control antigens produced strong immune responses with serum antibody titres between 1:10 000 and 1:100 000. However, there was no significant difference in the level of antibodies in the follicular fluids and the serum either in the sheep immunized with 2GPI or in the control animals (Figure 2).
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Discussion |
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The prevalence of aPLs in the general obstetric population is
1–2% (Lockwood et al., 1989; Pattison et al., 1993). In contrast, estimates of the incidence of aPLs in women with reproductive failure vary up to 50% depending on the number of antibodies tested for and the definitions of ‘positivity’ utilized (Gleicher et al., 1989; Dmowski et al., 1995; Kutteh, 1997). Although testing for large panels of aPLs may increase the number of women who test positive, these positive results do not necessarily correlate with clinical outcomes. Therefore, we limited our study to examining levels of the well-described aPLs: anti-PS, anti-CL and anti-2GPI. Our finding that the incidence of aPLs in infertile women is 19% is similar to previous reports (Birkenfeld et al., 1994; Birdsall et al., 1996; Kaider et al., 1996; Kutteh et al., 1997).
Although it is now well established that there is an increased incidence of aPLs in infertile women, exactly how these antibodies, which are present in the blood, could affect the viability of an embryo, particularly one that is produced in vitro, is unclear. However, a small study suggested that aPLs might be selectively concentrated in the follicular fluid (el-Roeiy et al., 1987). These workers examined the levels of multiple autoantibodies in follicular fluids and matched sera from 26 women. They found selective concentration of some aPLs, especially those of the IgM class, in follicular fluids. They also found a non-significant reduction in the pregnancy rates of women with aPLs compared with control women (5.4% compared with 21.6%). That study suggested the possibility that serum levels of aPLs might not accurately reflect the levels of aPLs in the follicular fluid microenvironment in which the oocyte developed. The selective concentration of aPLs in the follicular fluid shown in that study also raised the possibility that some women may have false-negative aPL results if the test was performed on serum (el-Roeiy et al., 1987). Since this is a potentially important clinical question, we investigated the possibility that follicular fluids contain selectively concentrated aPLs by two parallel methods. First, we demonstrated that the levels of aPLs in the follicular fluids of women undergoing IVF were not higher than the levels of these antibodies in their serum. For this analysis, we used the 99th percentile as the cut-off value for determining which samples were positive. When we reanalysed our data using the less rigorous 95th percentile as the cut-off point, we did find one woman whose follicular fluids contained significantly more IgG anti-2GPI antibodies than her serum. However, while this result is possibly interesting from a scientific point of view, we do not regard it as being clinically relevant as this woman also had elevated levels of IgM anti-CL, anti-PS and anti-2GPI antibodies in her serum when the 95th percentile was used as the cut-off point. The reanalysis of our data using the 95th percentile as the positive cut-off point raises an interesting issue. This reanalysis increased the percentage of women with aPLs from 19 to 56%. It also resulted in a large difference in the numbers of ongoing pregnancies/live births between the aPL-positive and aPL-negative groups (nine out of 55 = 16.4% versus 13 out of 44 = 29.5%). However, despite the large numerical difference, this difference remained statistically non-significant. This illustrates that lowering the cut-off point in the aPL assays does not increase the clinical value of the tests, rather this has the opposite effect of introducing a large number of false-positive test results.
Secondly, we demonstrated that despite high levels of anti-2GPI antibodies being present in the serum of sheep immunized with 2GPI, these antibodies were not concentrated in the follicular fluids of the animals we studied. These two results confirm that aPLs are not selectively concentrated in the follicular fluid and demonstrate that there is no diagnostic value in screening follicular fluids for aPLs.
It is also interesting that in contrast to el Roeiy et al. (1987), we did not find any IgM aPLs in the follicular fluids from the women in our study. Follicular fluid is believed to be largely a transudate from serum, and the lack of IgM antibodies in the follicular fluid is likely to be reflective of the large size of this molecule (900 kDa) compared with IgG (150 kDa), making it more difficult for IgM to enter the follicular environment by diffusion. Exactly why our results are so different from those of el Roeiy et al. is not clear, but collecting follicular fluids that are free of blood contamination is relatively difficult as the corpus luteum is a highly vascularized structure. In our experience, it is rare for follicular fluids obtained from women who have undergone ovarian stimulation to be free of blood contamination, and it may be that the differences between our results and those of el Roeiy et al. (1987) reflect different levels of blood contamination in the follicular fluids in the studies.
Our study demonstrated that women with aPLs have a poorer reproductive outcome than women without these antibodies, but the difference between these groups was not statistically significant. While it is very tempting to highlight the difference in outcomes and suggest this is a ‘non-statistical’ trend, the correct interpretation of the analysis is that the difference between the groups was nothing more than random chance. Our study found that the proportion of infertile women with aPLs was similar to that in other studies, and would suggest that these antibodies have no prognostic value in determining the outcome of a given IVF cycle. Therefore, there seems little point in routinely screening infertile women for aPLs. Furthermore, as aPL testing has no predictive value for IVF outcome, our data confirm the recommendations of others, including a recent meta-analysis, that there is no justification for the pharmacological intervention in women with aPLs whose clinical presentation is infertility (Hill and Scott, 2000; Hornstein, 2000; Hornstein et al., 2000).
However, having acknowledged the lack of predictive value of aPL testing in infertile women, this study raises the interesting point that the apparently large percentage difference in the pregnancy outcomes was not statistically significant. Given the relatively small sample size of our study, a post hoc power calculation was performed which showed that our study only had a power of 9.3% to show an 8% difference (23.8% minus 15.8%) in ongoing pregnancy/live birth rates between the groups. To provide a more statistically valid analysis, >1240 infertile women would need to be studied (assuming an aPL prevalence of 20%, 
= 0.05 and power = 80%). Such a trial would be difficult for many centres to conduct in a reasonable time frame, and a coordinated multicentre approach is likely to be required to settle once and for all the question of whether aPLs have any predictive value in infertile women. This would also require agreement on the type of antibodies that are to be measured and the cut-off values that are to be used.
Despite the outcomes of this study, there remains evidence that aPLs are associated with reduced fertility especially in women with recurrent IVF implantation failure (Birkenfeld et al., 1994; Geva et al., 1995; Balasch et al., 1996; Kaider et al., 1996). It may be that aPLs are simply an epiphenomenon or that aPLs do not directly cause infertility but rather that they are a marker of another pathogenic process occurring in some infertile women, as was suggested previously in other settings (Laskin and Soloninka, 1988; Rote et al., 1992). Alternatively, it may be that in some women aPLs do cause implantation failure but that this cannot be detected using population screening as we have attempted to do in this study. This raises the question ‘how could aPL cause in vitro fertilized oocytes to fail to implant’? The hypothesis underlying this study was that aPLs in the follicular fluid may bind to the oocyte in vivo then affect later embryonic development since aPLs have been shown to affect various trophoblast functions including invasion, differentiation, proliferation and hormone production (Di Simone et al., 1995, 2002, 2005; Chamley et al., 1998; Quenby et al., 2005). These are all effects of aPLs on fetal cells, particularly trophoblasts. However, it has been shown recently that aPLs can also affect the process of decidualization (Mak et al., 2002). These workers demonstrated that aPLs prevent the decidualization reaction that transforms the endometrium to support an implanting embryo. Since these endometrial cells are maternal, they are exposed to maternal aPL-containing blood, and this seems a reasonable mechanism by which maternal aPLs could cause implantation failure.
In conclusion, our study corroborates the prevalence of aPLs in infertile women, as well as confirming that the presence of aPLs is not an indicator of a poor outcome from IVF for women with these antibodies. Furthermore, our study contradicts an earlier report that suggested that aPLs may be selectively concentrated in the follicular fluid.
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Acknowledgements |
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We would like to thank Mrs A.Moore (University of Auckland) and Mr L.McGowan (AgResearch) for their excellent technical assistance, and Ms Y.Yu (University of Auckland) for statistical support. We are also very appreciative of the staff of Fertility Plus for their assistance in patient recruitment and sample collection. This research was funded by grants from the Auckland Medical Research Foundation and the University of Auckland Staff Research Fund.
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References |
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Balasch J, Creus M, Fabregues F, Reverter J, Carmona F, Tassies D, Font J and Vanrell J (1996) Antiphospholipid antibodies and human reproductive failure. Hum Reprod 11,2310–2315.
Birdsall MA, Lockwood GM, Ledger WL, Johnson PM and Chamley LW (1996) Antiphospholipid antibodies in women having in-vitro fertilization. Hum Reprod 11,1185–1189.
Birkenfeld A, Mukaida T, Minichiello L, Jackson M, Kase NG and Yemini M (1994) Incidence of autoimmune antibodies in failed embryo transfer cycles. Am J Reprod Immunol 31,65–68.
Chamley LW (2002) Antiphospholipid antibodies: biological basis and prospects for treatment. J Reprod Immunol 57,185–202.[CrossRef][Web of Science][Medline]
Chamley LW, Duncalf AM, Mitchell MD and Johnson PM (1998) Action of anticardiolipin and antibodies to beta2-glycoprotein-I on trophoblast proliferation as a mechanism for fetal death. Lancet 352,1037–1038.[CrossRef][Web of Science][Medline]
De Wolf F, Carreras LO, Moerman P, Vermylen J, Van Assche A and Renaer M (1982) Decidual vasculopathy and extensive placental infarction in a patient with repeated thromboembolic accidents, recurrent fetal loss, and a lupus anticoagulant. Am J Obstet Gynecol 142,829–834.[Web of Science][Medline]
DiSimone N, De Carolis S, Lanzone A, Ronsisvalle E, Giannice R and Caruso A (1995) In vitro effect of antiphospholipid antibody-containing sera on basal and gonadotrophin releasing hormone-dependent human chorionic gonadotrophin release by cultured trophoblast cells. Placenta 16,75–83.[CrossRef][Web of Science][Medline]
DiSimone N, Castellani R, Caliandro D and Caruso A (2002) Antiphospholipid antibodies regulate the expression of trophoblast cell adhesion molecules. Fertil Steril 77,805–811.[CrossRef][Web of Science][Medline]
DiSimone N, Raschi E, Testoni C, Castellani R, D’Asta M, Shi T, Krilis SA, Caruso A and Meroni PL (2005) Pathogenic role of anti-beta 2-glycoprotein I antibodies in antiphospholipid associated fetal loss: characterisation of beta 2-glycoprotein I binding to trophoblast cells and functional effects of anti-beta 2-glycoprotein I antibodies in vitro. Ann Rheum Dis 64,462–467.
Dmowski W, Friberg J, Rana N, Papierniak C, Michalowska J and El-Roeiy A (1995) The effect of endometriosis, its stage and activity, and of autoantibodies on in vitro fertilization and embryo transfer success rates. Fertil Steril 63,555–562.[Web of Science][Medline]
el-Roeiy A, Gleicher N, Friberg J, Confino E and Dudkiewicz A (1987) Correlation between peripheral blood and follicular fluid autoantibodies and impact on in vitro fertilization. Obstet Gynecol 70,163–170.[Web of Science][Medline]
Geva E, Amit A, Lerner-Geva L, Azem F, Yovel I and Lessing J (1995) Autoimmune disorders: another possible cause for in-vitro fertilization and embryo transfer failure. Hum Reprod 10,2560–2563.
Gleicher N, El-Roeiy A, Confino E and Friberg J (1989) Reproductive failure because of autoantibodies: unexplained infertility and pregnancy wastage. Am J Obstet Gynecol 160,1376–1385.[Web of Science][Medline]
Hill JA and Scott RT (2000) Immunologic tests and IVF: ‘please, enough already’. Fertil Steril 74,439–442.[CrossRef][Web of Science][Medline]
Hornstein MD (2000) Antiphospholipid antibodies in patients undergoing IVF: the data do not support testing. Fertil Steril 74 635–636.[CrossRef][Web of Science][Medline]
Hornstein MD, Davis OK, Massey JB, Paulson RJ and Collins JA (2000) Antiphospholipid antibodies and in vitro fertilization success: a meta-analysis. Fertil Steril 73,330–333.[CrossRef][Web of Science][Medline]
Johns A, Chamley L, Ockelford P, Pattison N, McKay E, Corkill M and Hart H (1994) Comparison of tests for the lupus anticoagulant and antiphospholipid antibodies in systemic lupus erythematosus. Clin Exp Rheumatol 12,523–526.[Web of Science][Medline]
Kaider B, Price D, Roussev R and Coulam C (1996) Antiphospholipid antibody prevalence in patients with IVF failure. Am J Reprod Immunol 35,388–393.
Kaider B, Coulam C and Roussev R (1999) Murine embryos as a direct target for some human autoantibodies in vitro. Hum Reprod 14,2556–2561.
Kutteh W. (1997) Antiphospholipid antibodies and reproduction. J Reprod Immunol 35,151–171.[CrossRef][Web of Science][Medline]
Kutteh W, Yetman D, Chantilis S and Crain J (1997) Effect of antiphospholipid antibodies in women undergoing in-vitro fertilization: role of heparin and aspirin. Hum Reprod 12,1171–1175.
Laskin CA and Soloninka CA (1988) Anticardiolipin antibodies: smoking gun or smoke screen? J Rheumatol 15,7–9.[Web of Science][Medline]
Lockwood CJ, Romero R, Feinberg RF, Clyne LP, Coster B and Hobbins JC (1989) The prevalence and biologic significance of lupus anticoagulant and anticardiolipin antibodies in a general obstetric population. Am J Obstet Gynecol 161,369–373.[Web of Science][Medline]
Mak IY, Brosens JJ, Christian M, Hills FA, Chamley L, Regan L and White JO (2002) Regulated expression of signal transducer and activator of transcription, Stat5, and its enhancement of PRL expression in human endometrial stromal cells in vitro. J Clin Endocrinol Metab 87,2581–2588.
Pattison NS, Chamley LW, McKay EJ, Liggins GC and Butler WS (1993) Antiphospholipid antibodies in pregnancy: prevalence and clinical associations. Br J Obstet Gynaecol 100,909–913.[Web of Science][Medline]
Quenby S, Mountfield S, Cartwright JE, Whitley GS, Chamley L and Vince G (2005) Antiphospholipid antibodies prevent extravillous trophoblast differentiation. Fertil Steril 83,691–698.[CrossRef][Web of Science][Medline]
Rote NS, Walter A and Lyden TW (1992) Antiphospholipid antibodies—lobsters or red herrings? Am J Reprod Immunol 28,31–37.
Stern C, Chamley L, Hale L, Kloss M, Speirs A and Baker HW (1998) Antibodies to beta2 glycoprotein I are associated with in vitro fertilization implantation failure as well as recurrent miscarriage: results of a prevalence study. Fertil Steril 70,938–944.[CrossRef][Web of Science][Medline]
Sthoeger ZM, Mozes E and Tartakovsky B (1993) Anti-cardiolipin antibodies induce pregnancy failure by impairing embryonic implantation. Proc Natl Acad Sci USA 90,6464–6467.
Submitted on August 16, 2005; resubmitted on September 17, 2005; accepted on September 26, 2005.
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