Journal of Assisted Reproduction and Genetics, Vol. 9, No. 3, 1992
CLINICAL ASSISTED REPRODUCTION
Relation Between Antibodies to Chlamydia trachomatis and Spontaneous Abortion Following in Vitro Fertilization F. LICCIARDI, 1 J. A. GRIFO, 1 Z. ROSENWAKS, 1 and S. S. WITKIN 1'2
KEY WORDS: Chlamydia trachomatis; spontaneous abortion; in vitro fertilization.
Submitted: October 24, 1991 Accepted: January 17, 1992
Background: Many couples undergo in vitro fertilization
INTRODUCTION
due to occlusion of the fallopian tubes. Chlamydia trachomatis infections are a major cause of this tubal damage. Since this organism has also been associated with poor pregnancy outcome, we investigated whether a past exposure to C. trachomatis was associated with spontaneous abortion following in vitro fertilization and embryo transfer. Methods: Sera from 145 women undergoing IVF were diluted 1:128 and tested for IgG antibodies to C. trachomatis by an immunoperoxidase assay, using infected cells fixed to slides. All subjects and their partners were negative for C. trachomatis by culture or by DNA hybridization. Results: Serological evidence of a past chlamydial infection was observed in 33.8% of the women. The incidence of antichlamydial IgG was greater (P < 0.001) in women whose infertility was due to known tubal disease (37 of 78; 47.4%) than in women whose infertility was due to other causes (12 of 67; 17.9%). Spontaneous abortions after embryo transfer occurred in 20% of the subjects. The incidence of antichlamydial IgG in aborting women (20 of 29; 69.0%) was greater (P < 0.001) than the incidence in either women with successful pregnancies (9 of 38; 23.7%) or women who did not become pregnant (20 of 78; 25.6%) after IVF. No relation was observed between antichlamydial antibody status and maternal age, the number of oocytes aspirated, the number of oocytes fertilized, and the number of embryos transferred. Conclusions: A previous infection with C. trachomatis may increase susceptibility to subsequent spontaneous abortion, even in the absence of a detectable current infection.
The advent of in vitro fertilization (IVF) has led to increased birth rates for women with tubal disease, endometriosis, endocrine or immunological disorders, or unexplained infertility or whose husbands have sperm abnormalities. However, the percentage of IVF pregnancies which end in spontaneous abortion remains high. Approximately 13% of IVF conceptions which develop to the point of a gestational sac end in spontaneous abortion (1). Although some of these abortions are due to genetic or anatomic factors, the majority remains unexplained. Detection of a mechanism responsible for these abortions is critical in order to devise strategies to decrease their occurrence. In this communication, we evaluated the association between prior infection with Chlamydia trachomatis and spontaneous abortion after IVF. Previous studies have suggested a possible relationship between IgG antichlamydial antibodies and adverse pregnancy outcome. Quinn et al., studying women who had achieved spontaneous pregnancies, demonstrated that women with a history of more than one spontaneous abortion had a significantly higher incidence of IgG antibodies to Chlamydia than did fertile or infertile women with fewer than two abortions (2). In patients undergoing IVF, Rowland et al. demonstrated that the presence of IgG antichlamydial antibodies correlated with a negative pregnancy outcome (3). In this study, no distinction was made between failure to achieve pregnancy and spontaneous abortion. Additional reports have either supported or refuted these findings. Torode et al. found no association between seropositivity to
1 Department of Obstetrics and Gynecology, Cornell University Medical College, 525 East 68th Street, New York, New York 10021. z To whom correspondence should be addressed.
207
I058-0468/92/0600-0207506.50/0 © 1992 Plenum PublishingCorporation
208
C. trachomatis and pregnancy outcome in IVF/ gamete intrafallopian transfer (GIFT) patients (4). Lunenfeld et al., however, showed a strong association between antichlamydial antibodies and poor pregnancy outcome in IVF patients (5); 58% of patients with either spontaneous abortion, biochemical or ectopic pregnancies, or no pregnancies were positive for these antibodies, as compared to 29% seropositivity in women with successful pregnancies.
LICCIARDI, GRIFO, ROSENWAKS, AND WITKIN
by a delivery or, if delivery had not yet occurred, the presence of a fetal heartbeat beyond the first trimester.
RESULTS Cervical Chlamydia Detection None of the 145 patients were positive for C. trachomatis when tested by either culture or DNA probe.
MATERIALS AND METHODS One hundred forty-five women undergoing IVF at the New York Hospital-Cornell Medical Center were studied. Each women was tested for C. trachomatis by rotating a Dacron swab in the endocervical canal, transferring the swab to sucrosephosphate buffer transport medium, and either testing for growth on cyclohexemide-treated McCoy cell monolayers or assaying for Chlamydia DNA using an oligonucleotide probe (Gen Probe, San Diego, CA). Controlled ovarian hyperstimulation was performed using gonadotropins with or without gonadotropin releasing hormone (GnRH) analogue. Daily determinations of estradiol levels and follicular mean diameters were used to time human chorionic gonadotropin (hCG) administration. Oocyte retrieval was performed via transvaginal ultrasoundguided follicular aspiration. Embryo replacement was intrauterine. Serum was obtained on IVF cycle day 6, which corresponded to the third day of gonadotropin stimulation. All sera were assayed for anti-C, trachomatis IgG antibodies by an immunoperoxidase technique (ICN Biomedical, Costa Mesa, CA). Sera were diluted 1:128 in phosphate-buffered saline and incubated on slides containing C. trachomatis strain L2-infected McCoy cells. Positive and negative control sera were tested on the same slide. After 45 min at 37°C, the slides were washed, dried, and incubated with a horseradish peroxidase-conjugated antibody to human IgG. After a second 45-min incubation, the slides were washed, dried, covered with a coverslip, and examined under magnification. Positive samples exhibited dark blue cytoplasmic inclusions. A spontaneous abortion was defined as a pregnancy loss after establishment of a gestational sac or fetal heart. An ongoing pregnancy was defined
IgG Antibodies to C. trachomatis and Cause of Infertility As determined by chart review, interviews, and physical examination, tubal disease (tubal dilatation or obstruction or the presence of pelvic adhesions) was the primary cause of infertility in 78 (53.8%) of the patients, while 67 (46.2%) had other causes for their infertility. In five patients, tubal-factor infertility was not related to infection but to a previous tubal ligation or ectopic pregnancy with normal pelvic anatomy. Antibodies to C. trachomatis were most prevalent in women with a history of tubal disease (Table I). IgG antichlamydial antibodies were present in 47.4% of women with tubal disease, as opposed to 17.9% of women with other causes of infertility (P < 0.001). IgG Antibodies to C. trachomatis and Pregnancy Outcome Spontaneous abortions following IVF occurred in 29 of the women (20%). The incidence of antiTable I. Incidence of Chlamydia IgG Antibodies in Relation to Infertility Etiology in Women Undergoing IVF a Cause of infertility
No. subjects
No. Chlamydia IgG positive (%)
Tubal disease Other Male factor Endometriosis Idiopathic Tubal (noninfectious) Diethylstilbesterol exposure Immunological
78 67 22 17 19 5
37 (47.4) 12 (17.9) 2 3 4 2
3 1
1 0
Sera were tested for antibodies to C. trachomatis by an immunoperoxidose assay employing infected McCoy cells.
Journal of Assisted Reproduction and Genetics, Vol. 9, No. 3, 1992
CHLAMYDIAL ANTIBODIES AND SPONTANEOUS ABORTION
209
chlamydial antibodies in these women (69.0%) was significantly higher (P = 0.001) than the 23.7% incidence in women with successful pregnancies and the 25.6% incidence in women whose transferred embryos did not implant (Table II). Women with antichlamydial antibodies did not differ in mean age from those who were seronegative (34.4 -+ 6.7 vs 35.8 -+ 3.0 years, respectively).
Table III. Relation Between IgG Antibodies to C. trachomatis and Number of Eggs Retrieved, Eggs Fertilized, and Embryos Transferred
Antibodies to C. trachomatis and Oocyte Maturation, Fertilization and Development The presence of antichlamydial antibodies was unrelated to the ovarian response to gonadotropin stimulation as measured by the mean number of oocytes aspirated per patient. The presence of antichlamydial antibodies also did not influence the fertilization rate or embryo viability up to the point of intrauterine replacement (Table III).
DISCUSSION Our finding of an almost threefold higher incidence of IgG antibodies to C. trachomatis in patients with tubal disease is consistent with previous studies detailing an association between these antibodies and tubal-factor infertility (6-8). An upper genital tract infection with C. trachomatis is a leading cause of tubal occlusion. We think it is improbable that the elevated incidence of spontaneous abortions in our IVF patients with IgG antibodies to C. trachomatis was due to the presence of viable C. trachomatis in the reproductive tract at the time of embryo transfer. None of these women were positive for this organism in the cervix by culture or by DNA hybridization. There are several possible mechanisms whereby a prior chlamydial infection could adversely affect pregnancy outcome. A single 57-kD protein, a member of the 60-kD heat shock protein family, has been implicated in the induction of a delayed hyperTable II. Relation Between Pregnancy Outcome After IVF and the Presence of IgG Chlamydia Antibodies
IVF outcome
No. subjects
No. Chlamydia IgG positive (%)
Ongoing Spontaneous abortion Not pregnant
38 29 78
9 (23.7) 20 (69.0) 20 (25.6)
Journal of Assisted Reproduction and Genetics, Vol. 9, No. 3, 1992
Mean number (SD) Antibodies
Oocytes aspirated
Oocytes fertilized
Embryos transferred
Present Absent
8.5 (7.1) 8.8 (5.7)
6.0 (5.2) 5.0 (3.7)
3.0 (1.1) 2.9 (1.2)
sensitivity reaction to C. trachomatis (9). It has been postulated that the synthesis and release of this 57-kD antigen in persistent nonproductive chlamydial infections could result in prolonged inflammation (9). A chronic intracellular infection in the uterus could lead to the synthesis and release of soluble chlamydial antigens. This would evoke a subclinical chronic inflammatory response in the endometrium. Alternatively, as we have previously demonstrated (10), an immune response to Chlamydia leads to interferon gamma release from activated T lymphocytes at the site of infection. This can induce the expression of major histocompatibility complex (MHC) class 2 antigens on epithelial cells in the female reproductive tract, converting them to cells capable of presenting epithelial antigens to T lymphocytes. This can result in the generation of epithelial-specific cytotoxic T cells that can react with epithelial cell surfaces and cause autoimmune damage, in the absence of infection. T lymphocytes that were sensitized to the chlamydial 57-kD heat shock protein may also cross-react with and lyse cells expressing the homologous human heat shock protein (11), which may also be expressed on the surface of stressed cells (12). Damage to the endometrium or myometrium may occur by either of these mechanisms, rendering the uterus less effective for implantation or for more advanced placentation. Alternatively, lymphocytes sensitized as a result of a chlamydial infection may recognize fetal antigens, leading to pregnancy failure through a direct attack of the fetus. Heat shock protein has been identified in murine two-cell embryos (13). We are currently utilizing the polymerase chain reaction to increase the sensitivity of our analysis for the possible continued presence of C. trachomatis in the cervix of our IVF patients. If evidence of a current infection can be found, then a course of antibiotic treatment prior to IVF, in women who are positive for chlamydial antibodies, may reduce the incidence of spontaneous abortion. Alternatively, if
210
T lymphocytes that are responsive to epithelial antigens or to fetal components can be found in women with past chlamydial infections, then methods to inhibit the cell-mediated immune response during early pregnancy may be required to lower the incidence of spontaneous abortions. REFERENCES 1. Steer C, Campbell S, Davies M, Mason B, Collins W: Spontaneous abortion rates after natural and assisted conception. Br Med J 1988;299:1317-1318 2. Quinn P, Petric M, Barkin M: The prevalence of antibody to Chlamydia trachomatis in spontaneous abortion and infertility. Am J Obstet Gynecol 1987;156:291-296 3. Rowland G, Forsey T, Moss T, Steptoe P, Hewitt J, Darougar S: Failure of in vitro fertilization and embryo replacement following infection with Chlamydia trachomatis. J Vitro Fert Embryo Transfer 1985;2:151-155 4. Torode HN, Wheeler PA, Saunders DM, McPetfic RA, Medcalf SC, Ackerman VP: The role of Chlamydia antibodies in an in vitro fertilization program. Fertil Steril 1987;48: 987-990 5. Lunenfeld E, Shapiro BS, Sarov B, Sarov I, Insler V, Decherney A: The association between Chlamydia-specific IgG and IgM antibodies and pregnancy outcome in an in vitro fertilization program. J Vitro Fert Embryo Transfer 1989;6: 222-227 6. Henry-Suchet J, Catalan F, Loffredo V, Serfaty D, Siboulet A, Perol Y, Sanson MJ, Debache C, Pigeau F, Coppin R,
LICCIARDI, GRIFO, ROSENWAKS~AND WITKIN
7.
8.
9.
10.
11.
12.
13.
DeBrux J, Poynard T: Microbiology of specimens obtained by laparoscopy from controls and from patients with pelvic inflammatory disease with tubal obstruction: Chlamydia trachomatis and Ureaplasma urealyticum. Am J Obstet Gynecol 1980;138:1022-1025 Gump D, Gibson M, Ashikaga T: Evidence of prior pelvic inflammatory disease and its relationship to Chlamydia trachomatis antibody and intrauterine contraceptive device use in infertile women. Am J Obstet Gynecol 1983;146:153-159 Thejls H, Gnarpe J, Lundkvist O, Heimer G, Larsson G, Victor A: Diagnosis and prevalence of persistent Chlamydia infection in infertile women: tissue culture, direct antigen detection and serology. Fertil Steril 1991;55:304-310 Morrison R, Lyng K, Caldwell H: Chlarnydial disease pathogenesis. Ocular hypersensitivity elicited by a genus-specific 57 kD protein. J Exp Med 1989;169:663-675 Grifo JA, Jeremias J, Ledger WJ, Witkin SS: Interferon gamma in the pathogenesis of pelvic inflammatory disease. Am J Obstet Gynecol 1989;160:26-31 Munk ME, Schoel B, Modrow S, Karr RW, Young RA, Kaufman HE: T lymphocytes from healthy individuals with specificity to self epitopes shared by the mycobacterial and human 65-kilodalton heat shock protein. J Immunol 1989; 143: 2844-2849 Wand-Wurttenberger A, Schoel B, Ivanyi J, Kaufman SH: Surface expression by mononuclear phagocyte of an epitope shared with mycobacterial heat shock protein 60. Eur J Immunol 1991;21:1089-1092 Bensaude O, Babinet C, Morange M, Jacob F: Heat shock proteins, first major products of zygotic gene activity in mouse embryo. Nature 1983;305:331-333
Journal of Assisted Reproduction and Genetics, Vol. 9, No. 3, 1992
CLINICAL ASSISTED REPRODUCTION
Relation Between Antibodies to Chlamydia trachomatis and Spontaneous Abortion Following in Vitro Fertilization F. LICCIARDI, 1 J. A. GRIFO, 1 Z. ROSENWAKS, 1 and S. S. WITKIN 1'2
KEY WORDS: Chlamydia trachomatis; spontaneous abortion; in vitro fertilization.
Submitted: October 24, 1991 Accepted: January 17, 1992
Background: Many couples undergo in vitro fertilization
INTRODUCTION
due to occlusion of the fallopian tubes. Chlamydia trachomatis infections are a major cause of this tubal damage. Since this organism has also been associated with poor pregnancy outcome, we investigated whether a past exposure to C. trachomatis was associated with spontaneous abortion following in vitro fertilization and embryo transfer. Methods: Sera from 145 women undergoing IVF were diluted 1:128 and tested for IgG antibodies to C. trachomatis by an immunoperoxidase assay, using infected cells fixed to slides. All subjects and their partners were negative for C. trachomatis by culture or by DNA hybridization. Results: Serological evidence of a past chlamydial infection was observed in 33.8% of the women. The incidence of antichlamydial IgG was greater (P < 0.001) in women whose infertility was due to known tubal disease (37 of 78; 47.4%) than in women whose infertility was due to other causes (12 of 67; 17.9%). Spontaneous abortions after embryo transfer occurred in 20% of the subjects. The incidence of antichlamydial IgG in aborting women (20 of 29; 69.0%) was greater (P < 0.001) than the incidence in either women with successful pregnancies (9 of 38; 23.7%) or women who did not become pregnant (20 of 78; 25.6%) after IVF. No relation was observed between antichlamydial antibody status and maternal age, the number of oocytes aspirated, the number of oocytes fertilized, and the number of embryos transferred. Conclusions: A previous infection with C. trachomatis may increase susceptibility to subsequent spontaneous abortion, even in the absence of a detectable current infection.
The advent of in vitro fertilization (IVF) has led to increased birth rates for women with tubal disease, endometriosis, endocrine or immunological disorders, or unexplained infertility or whose husbands have sperm abnormalities. However, the percentage of IVF pregnancies which end in spontaneous abortion remains high. Approximately 13% of IVF conceptions which develop to the point of a gestational sac end in spontaneous abortion (1). Although some of these abortions are due to genetic or anatomic factors, the majority remains unexplained. Detection of a mechanism responsible for these abortions is critical in order to devise strategies to decrease their occurrence. In this communication, we evaluated the association between prior infection with Chlamydia trachomatis and spontaneous abortion after IVF. Previous studies have suggested a possible relationship between IgG antichlamydial antibodies and adverse pregnancy outcome. Quinn et al., studying women who had achieved spontaneous pregnancies, demonstrated that women with a history of more than one spontaneous abortion had a significantly higher incidence of IgG antibodies to Chlamydia than did fertile or infertile women with fewer than two abortions (2). In patients undergoing IVF, Rowland et al. demonstrated that the presence of IgG antichlamydial antibodies correlated with a negative pregnancy outcome (3). In this study, no distinction was made between failure to achieve pregnancy and spontaneous abortion. Additional reports have either supported or refuted these findings. Torode et al. found no association between seropositivity to
1 Department of Obstetrics and Gynecology, Cornell University Medical College, 525 East 68th Street, New York, New York 10021. z To whom correspondence should be addressed.
207
I058-0468/92/0600-0207506.50/0 © 1992 Plenum PublishingCorporation
208
C. trachomatis and pregnancy outcome in IVF/ gamete intrafallopian transfer (GIFT) patients (4). Lunenfeld et al., however, showed a strong association between antichlamydial antibodies and poor pregnancy outcome in IVF patients (5); 58% of patients with either spontaneous abortion, biochemical or ectopic pregnancies, or no pregnancies were positive for these antibodies, as compared to 29% seropositivity in women with successful pregnancies.
LICCIARDI, GRIFO, ROSENWAKS, AND WITKIN
by a delivery or, if delivery had not yet occurred, the presence of a fetal heartbeat beyond the first trimester.
RESULTS Cervical Chlamydia Detection None of the 145 patients were positive for C. trachomatis when tested by either culture or DNA probe.
MATERIALS AND METHODS One hundred forty-five women undergoing IVF at the New York Hospital-Cornell Medical Center were studied. Each women was tested for C. trachomatis by rotating a Dacron swab in the endocervical canal, transferring the swab to sucrosephosphate buffer transport medium, and either testing for growth on cyclohexemide-treated McCoy cell monolayers or assaying for Chlamydia DNA using an oligonucleotide probe (Gen Probe, San Diego, CA). Controlled ovarian hyperstimulation was performed using gonadotropins with or without gonadotropin releasing hormone (GnRH) analogue. Daily determinations of estradiol levels and follicular mean diameters were used to time human chorionic gonadotropin (hCG) administration. Oocyte retrieval was performed via transvaginal ultrasoundguided follicular aspiration. Embryo replacement was intrauterine. Serum was obtained on IVF cycle day 6, which corresponded to the third day of gonadotropin stimulation. All sera were assayed for anti-C, trachomatis IgG antibodies by an immunoperoxidase technique (ICN Biomedical, Costa Mesa, CA). Sera were diluted 1:128 in phosphate-buffered saline and incubated on slides containing C. trachomatis strain L2-infected McCoy cells. Positive and negative control sera were tested on the same slide. After 45 min at 37°C, the slides were washed, dried, and incubated with a horseradish peroxidase-conjugated antibody to human IgG. After a second 45-min incubation, the slides were washed, dried, covered with a coverslip, and examined under magnification. Positive samples exhibited dark blue cytoplasmic inclusions. A spontaneous abortion was defined as a pregnancy loss after establishment of a gestational sac or fetal heart. An ongoing pregnancy was defined
IgG Antibodies to C. trachomatis and Cause of Infertility As determined by chart review, interviews, and physical examination, tubal disease (tubal dilatation or obstruction or the presence of pelvic adhesions) was the primary cause of infertility in 78 (53.8%) of the patients, while 67 (46.2%) had other causes for their infertility. In five patients, tubal-factor infertility was not related to infection but to a previous tubal ligation or ectopic pregnancy with normal pelvic anatomy. Antibodies to C. trachomatis were most prevalent in women with a history of tubal disease (Table I). IgG antichlamydial antibodies were present in 47.4% of women with tubal disease, as opposed to 17.9% of women with other causes of infertility (P < 0.001). IgG Antibodies to C. trachomatis and Pregnancy Outcome Spontaneous abortions following IVF occurred in 29 of the women (20%). The incidence of antiTable I. Incidence of Chlamydia IgG Antibodies in Relation to Infertility Etiology in Women Undergoing IVF a Cause of infertility
No. subjects
No. Chlamydia IgG positive (%)
Tubal disease Other Male factor Endometriosis Idiopathic Tubal (noninfectious) Diethylstilbesterol exposure Immunological
78 67 22 17 19 5
37 (47.4) 12 (17.9) 2 3 4 2
3 1
1 0
Sera were tested for antibodies to C. trachomatis by an immunoperoxidose assay employing infected McCoy cells.
Journal of Assisted Reproduction and Genetics, Vol. 9, No. 3, 1992
CHLAMYDIAL ANTIBODIES AND SPONTANEOUS ABORTION
209
chlamydial antibodies in these women (69.0%) was significantly higher (P = 0.001) than the 23.7% incidence in women with successful pregnancies and the 25.6% incidence in women whose transferred embryos did not implant (Table II). Women with antichlamydial antibodies did not differ in mean age from those who were seronegative (34.4 -+ 6.7 vs 35.8 -+ 3.0 years, respectively).
Table III. Relation Between IgG Antibodies to C. trachomatis and Number of Eggs Retrieved, Eggs Fertilized, and Embryos Transferred
Antibodies to C. trachomatis and Oocyte Maturation, Fertilization and Development The presence of antichlamydial antibodies was unrelated to the ovarian response to gonadotropin stimulation as measured by the mean number of oocytes aspirated per patient. The presence of antichlamydial antibodies also did not influence the fertilization rate or embryo viability up to the point of intrauterine replacement (Table III).
DISCUSSION Our finding of an almost threefold higher incidence of IgG antibodies to C. trachomatis in patients with tubal disease is consistent with previous studies detailing an association between these antibodies and tubal-factor infertility (6-8). An upper genital tract infection with C. trachomatis is a leading cause of tubal occlusion. We think it is improbable that the elevated incidence of spontaneous abortions in our IVF patients with IgG antibodies to C. trachomatis was due to the presence of viable C. trachomatis in the reproductive tract at the time of embryo transfer. None of these women were positive for this organism in the cervix by culture or by DNA hybridization. There are several possible mechanisms whereby a prior chlamydial infection could adversely affect pregnancy outcome. A single 57-kD protein, a member of the 60-kD heat shock protein family, has been implicated in the induction of a delayed hyperTable II. Relation Between Pregnancy Outcome After IVF and the Presence of IgG Chlamydia Antibodies
IVF outcome
No. subjects
No. Chlamydia IgG positive (%)
Ongoing Spontaneous abortion Not pregnant
38 29 78
9 (23.7) 20 (69.0) 20 (25.6)
Journal of Assisted Reproduction and Genetics, Vol. 9, No. 3, 1992
Mean number (SD) Antibodies
Oocytes aspirated
Oocytes fertilized
Embryos transferred
Present Absent
8.5 (7.1) 8.8 (5.7)
6.0 (5.2) 5.0 (3.7)
3.0 (1.1) 2.9 (1.2)
sensitivity reaction to C. trachomatis (9). It has been postulated that the synthesis and release of this 57-kD antigen in persistent nonproductive chlamydial infections could result in prolonged inflammation (9). A chronic intracellular infection in the uterus could lead to the synthesis and release of soluble chlamydial antigens. This would evoke a subclinical chronic inflammatory response in the endometrium. Alternatively, as we have previously demonstrated (10), an immune response to Chlamydia leads to interferon gamma release from activated T lymphocytes at the site of infection. This can induce the expression of major histocompatibility complex (MHC) class 2 antigens on epithelial cells in the female reproductive tract, converting them to cells capable of presenting epithelial antigens to T lymphocytes. This can result in the generation of epithelial-specific cytotoxic T cells that can react with epithelial cell surfaces and cause autoimmune damage, in the absence of infection. T lymphocytes that were sensitized to the chlamydial 57-kD heat shock protein may also cross-react with and lyse cells expressing the homologous human heat shock protein (11), which may also be expressed on the surface of stressed cells (12). Damage to the endometrium or myometrium may occur by either of these mechanisms, rendering the uterus less effective for implantation or for more advanced placentation. Alternatively, lymphocytes sensitized as a result of a chlamydial infection may recognize fetal antigens, leading to pregnancy failure through a direct attack of the fetus. Heat shock protein has been identified in murine two-cell embryos (13). We are currently utilizing the polymerase chain reaction to increase the sensitivity of our analysis for the possible continued presence of C. trachomatis in the cervix of our IVF patients. If evidence of a current infection can be found, then a course of antibiotic treatment prior to IVF, in women who are positive for chlamydial antibodies, may reduce the incidence of spontaneous abortion. Alternatively, if
210
T lymphocytes that are responsive to epithelial antigens or to fetal components can be found in women with past chlamydial infections, then methods to inhibit the cell-mediated immune response during early pregnancy may be required to lower the incidence of spontaneous abortions. REFERENCES 1. Steer C, Campbell S, Davies M, Mason B, Collins W: Spontaneous abortion rates after natural and assisted conception. Br Med J 1988;299:1317-1318 2. Quinn P, Petric M, Barkin M: The prevalence of antibody to Chlamydia trachomatis in spontaneous abortion and infertility. Am J Obstet Gynecol 1987;156:291-296 3. Rowland G, Forsey T, Moss T, Steptoe P, Hewitt J, Darougar S: Failure of in vitro fertilization and embryo replacement following infection with Chlamydia trachomatis. J Vitro Fert Embryo Transfer 1985;2:151-155 4. Torode HN, Wheeler PA, Saunders DM, McPetfic RA, Medcalf SC, Ackerman VP: The role of Chlamydia antibodies in an in vitro fertilization program. Fertil Steril 1987;48: 987-990 5. Lunenfeld E, Shapiro BS, Sarov B, Sarov I, Insler V, Decherney A: The association between Chlamydia-specific IgG and IgM antibodies and pregnancy outcome in an in vitro fertilization program. J Vitro Fert Embryo Transfer 1989;6: 222-227 6. Henry-Suchet J, Catalan F, Loffredo V, Serfaty D, Siboulet A, Perol Y, Sanson MJ, Debache C, Pigeau F, Coppin R,
LICCIARDI, GRIFO, ROSENWAKS~AND WITKIN
7.
8.
9.
10.
11.
12.
13.
DeBrux J, Poynard T: Microbiology of specimens obtained by laparoscopy from controls and from patients with pelvic inflammatory disease with tubal obstruction: Chlamydia trachomatis and Ureaplasma urealyticum. Am J Obstet Gynecol 1980;138:1022-1025 Gump D, Gibson M, Ashikaga T: Evidence of prior pelvic inflammatory disease and its relationship to Chlamydia trachomatis antibody and intrauterine contraceptive device use in infertile women. Am J Obstet Gynecol 1983;146:153-159 Thejls H, Gnarpe J, Lundkvist O, Heimer G, Larsson G, Victor A: Diagnosis and prevalence of persistent Chlamydia infection in infertile women: tissue culture, direct antigen detection and serology. Fertil Steril 1991;55:304-310 Morrison R, Lyng K, Caldwell H: Chlarnydial disease pathogenesis. Ocular hypersensitivity elicited by a genus-specific 57 kD protein. J Exp Med 1989;169:663-675 Grifo JA, Jeremias J, Ledger WJ, Witkin SS: Interferon gamma in the pathogenesis of pelvic inflammatory disease. Am J Obstet Gynecol 1989;160:26-31 Munk ME, Schoel B, Modrow S, Karr RW, Young RA, Kaufman HE: T lymphocytes from healthy individuals with specificity to self epitopes shared by the mycobacterial and human 65-kilodalton heat shock protein. J Immunol 1989; 143: 2844-2849 Wand-Wurttenberger A, Schoel B, Ivanyi J, Kaufman SH: Surface expression by mononuclear phagocyte of an epitope shared with mycobacterial heat shock protein 60. Eur J Immunol 1991;21:1089-1092 Bensaude O, Babinet C, Morange M, Jacob F: Heat shock proteins, first major products of zygotic gene activity in mouse embryo. Nature 1983;305:331-333
Journal of Assisted Reproduction and Genetics, Vol. 9, No. 3, 1992
