- Email: [email protected]
121: Extremes of fetal growth are associated with spontaneous preterm birth
SMFM Abstracts
www.AJOG.org 120
PROGESTERONE RECEPTOR GENE POLYMORPHISMS AND PREGNANCY-RELATED PARAMETERS IN A RACIALLY DIVERSE POPULATION DANIEL SKUPSKI1, IARA LINHARES2, NEIL NORMAND3, DEVRIM SEZEN2, OKSANA BABULA2, SHARI GELBER4, ANN MARIE BONGIOVANNI2, STEVEN S. WITKIN2, 1Cornell University, Flushing, New York, 2 Weill Medical College of Cornell University, Obstetrics and Gynecology, New York, New York, 3Cornell University Medical College, Obstetrics and Gynecology, New York, New York, 4Weill Medical College of Cornell University, Obstetrics and Gynecology, New York OBJECTIVE: The progesterone receptor (PR) exists in two isoforms, PR-A and PR-B. Both are products of the same gene and have different promoter sites. Progesterone binding to PR-B activates progesterone-responsive genes while binding to PR-A is without agonist activity and inhibits progesterone functions. A single G⬎A polymorphism at position ⫹331 in the PR gene results in increased production of PR-B, a decrease in the PR-A/PR-B ratio and has been associated with abnormal endometrial development. Since progesterone has diverse functions during gestation, we hypothesized that possession of the G⬎A polymorphism would influence pregnancy-related parameters. STUDY DESIGN: The borough of Queens has the most diverse racial/ethnic population in the United States. Buccal swabs were collected from 469 motherinfants pairs (2:1, term birth to preterm birth) and tested for the PR G⬎A polymorphism by gene amplification. Clinical and demographic parameters were collected and analyzed after completion of all laboratory testing. RESULTS: Maternal carriage of the variant A allele was identified in 5/53 (9.4%) White women, 9/111 (8.1%) Hispanics, 1/69 (1.4%) Blacks, 2/168 (1.2%) Asians and 0/58 East Indians (Ó2 for trend ⫽.0001). Only in Hispanic women was maternal allele A carriage associated with a higher median pre-pregnancy weight (75.2 kg vs. 63.0 kg, P ⫽ .048), as well as an elevated weight at delivery (95.9 kg vs. 79.7 kg, P ⫽ .002). Evaluating the population as a whole, maternal A allele carriage occurred almost equally in women with a term (10/286, 3.5%) or preterm (8/183, 4.4%) birth. However, among women who delivered preterm, the A allele was associated with a prior history of spontaneous preterm birth [(4/21 preterm, (19.0%) vs. 4/156 at term, (2.5%) (P ⫽ .007)]. CONCLUSION: The G⬎A PR polymorphism varies in frequency among different ethnic groups. Allele A carriage may influence maternal weight gain in Hispanic women and susceptibility to a repeat spontaneous preterm birth. Analysis of Hispanic women for this polymorphism may have clinical utility.
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0002-9378/$ - see front matter doi:10.1016/j.ajog.2007.10.131
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CERVICAL FETAL FIBRONECTIN: AN INDEX OF INTRA-AMNIOTIC INFLAMMATION, HISTOLOGIC CHORIOAMNIONITIS AND IMPENDING PRETERM DELIVERY IN PATIENTS WITH PRETERM LABOR AND INTACT MEMBRANES JI HYUN KANG1, SI EUN LEE1, CHAN-WOOK PARK1, JONG KWAN JUN1, ROBERTO ROMERO2, BO HYUN YOON1, 1Seoul National University College of Medicine, Obstetrics and Gynecology, Seoul, South Korea, 2National Institute of Child Health & Human Development/National Institutes of Health/Department of Health & Human Services, Perinatology Research Branch, Detroit, Michigan OBJECTIVE: To determine if an elevated concentration of a cervical fetal fibronection (FFN) is a risk factor for amniotic fluid (AF) infection, AF inflammation, histologic chorioamnionitis and shorter amniocentesis-to-delivery interval in patients with preterm labor and intact membranes. STUDY DESIGN: Cervical FFN test was performed in 124 singleton pregnant women (ⱕ35 weeks of gestation) with preterm labor and intact membranes at the time of amniocentesis. AF was cultured for aerobic and anaerobic bacteria and for genital mycoplasmas. AF inflammation was defined as an elevated AF matrix metalloproteinase-8 (MMP-8) concentration (⬎23 ng/mL). Nonparametric tests and survival techniques were used for analysis. RESULTS: 1) Patients with an elevated FFN had a significantly lower gestational age at birth, shorter amniocentesis-to-delivery interval and higher median AF MMP-8 and higher rates of a positive AF culture, AF inflammation and spontaneous preterm delivery within 7 days and 2 weeks than those without an elevated FFN (p⬍.05 for each); 2) A FFN of ⱖ150 ng/mL had a better diagnostic performance in the identification of both AF inflammation and spontaneous preterm delivery than did a FFN of ⱖ50 ng/mL (p⬍.05 for specificity for each); 3) However, there was no significant relationship between an elevated FFN and histologic chorioamnionitis (p⬎.05); 4) Multivariate survival analysis indicated that both AF inflammation and a FFN of ⱖ150 ng/mL (but not ⱖ50 ng/mL) were associated with short latency periods (hazards ratio, 2.05 and 4.36; 95% confidence interval, 1.21-3.46 and 2.288.34, respectively; p⬍ .01). CONCLUSION: An elevated FFN was associated with short amniocentesis-todelivery interval and AF inflammation but not with histologic chorioamnionitis in patients with preterm labor and intact membranes. A FFN of ⱖ150 ng/mL had better diagnostic and prognostic performance than did a FFN of ⱖ50 ng/mL. 0002-9378/$ - see front matter doi:10.1016/j.ajog.2007.10.133
EXTREMES OF FETAL GROWTH ARE ASSOCIATED WITH SPONTANEOUS PRETERM BIRTH. RADEK BUKOWSKI1, FERGAL D. MALONE2, FLINT PORTER3, DAVID A. NYBERG4, CHRISTINE COMSTOCK5, GARY HANKINS1, KEITH EDDLEMAN6, SUSAN GROSS7, LORRAINE DUGOFF8, SABRINA D. CRAIGO9, ILAN E. TIMOR-TRITSCH10, STEPHEN R. CARR11, HONOR M. WOLFE12, MARY E. D’ALTON13, 1University of Texas Medical Branch, Obstetrics and Gynecology, Galveston, Texas, 2Royal College of Surgeons in Ireland, Obstetrics and Gynecology, Dublin, Ireland, 3University of Utah, Salt Lake City, Utah, 4The Fetal & Women’s Center of Arizona, OB/GYN Ultrasound, Scottsdale, Arizona, 5William Beaumont Hospital, Fetal Imaging Department, Royal Oak, Michigan, 6Mount Sinai Medical Center, Department of Obstetrics and Gynecology, New York, New York, 7Montefiore Medical Center/Albert Einstein College, OB-GYN and Women’s Health, Bronx, New York, 8University of Colorado Health Sciences Center, Ob/Gyn, Denver, Colorado, 9Tufts-New England Medical Center, Obstetrics and Gynecology, Boston, Massachusetts, 10NYU Medical Center, School of Medicine and Obstetrics & Gynecology, New York, New York, 11Women and Infants Hospital / Brown University, Maternal-Fetal Medicine, Providence, Rhode Island, 12University of North Carolina at Chapel Hill, Department of Obstetrics and Gynecology, Chapel Hill, North Carolina, 13Columbia University, OB/GYN Maternal Fetal Medicine, New York, New York OBJECTIVE: To determine the association between fetal growth and duration of pregnancy and incidence of preterm delivery. STUDY DESIGN: In a prospective cohort of 38,033 singleton pregnancies we estimated achieved percentiles of individual optimal birth weight – fetal growth potential (GP). Duration of pregnancy was estimated based on ultrasound measurement of crow-rump length between 10 4/7 and 13 6/7 weeks of pregnancy. Natural length of pregnancy was defined as gestational age at delivery in pregnancies uncomplicated by medical or obstetrical complications which may constitute indication for delivery. Pregnancies complicated by those conditions: congenital or chromosomal abnormalities, termination of pregnancy or stillbirth, chronic hypertension, pregnancy induced hypertension, preeclampsia, gestational and pre-gestational diabetes, placental abruption and placenta previa, were censored. The effects of GP ⬍10th and ⬎90th percentile on duration of pregnancy were evaluated using survival analysis-Cox regression. RESULTS: Comparing to normal growth (GP 10-90th percentile) GP ⬍10th but not GP ⬎90th percentile was associated with increased incidence of spontaneous preterm birth between 20 and 28 weeks (HR, 95% CI ⫽ 2.9, 1.5-5.8; p⫽0.002 and 0.7, 0.2-2.4; p⫽0.6, respectively). Both GP ⬍10th and GP ⬎90th percentile were associated with increased incidence of preterm birth between 28 and 34 weeks (HR, 95% CI ⫽ 2.9, 2.0-4.2; p⬍0.0001 and 2.1, 1.4-3.2; p⬍0.0001, respectively) and weaker associated with preterm birth between 34 and 37 weeks (HR, 95% CI ⫽ 1.3, 1.1-1.6; p⬍0.002 and 1.3, 1.1-1.5; p⬍0.01, respectively). At term, GP ⬍10th percentile was associated with significantly lower incidence of deliveries between 39 and 42 weeks (HR, 95% CI ⫽ 0.91, 0.87-0.96; p⫽0.001) while GP ⬎90th percentile with higher incidence of deliveries between 37 and 39 weeks (HR, 95% CI ⫽ 1.2, 1.1-1.3; p⬍0001) than normal growth. Proportional hazard assumption was met (p⬎0.05 for all). CONCLUSION: Both growth restriction and macrosomia are associated with early and late spontaneous preterm birth.
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IS PREMATURE LABOR A STATE OF PLATELET ACTIVATION? OFFER EREZ1, ROBERTO ROMERO1, DEBRA HOPPENSTEADT2, JAWED FAREED2, TINNAKORN CHAIWORAPONGSA3, JUAN PEDRO KUSANOVIC1, SHALI MAZAKI-TOVI3, FRANCESCA GOTSCH1, NANDOR GABOR THAN1, EDI VAISBUCH1, CHONG JAI KIM4, JIMMY ESPINOZA3, POOJA MITTAL3, CHIA-LING NHAN-CHANG3, NEIL HAMILL3, MOSHE MAZOR5, SONIA HASSAN3, 1Perinatology Research Branch, NICHD, NIH, DHHS, Detroit, Michigan, 2Loyola University Health System, Department of Pathology, Chicago, Illinois, 3 Wayne State University School of Medicine, Department of Obstetrics and Gynecology, Detroit, Michigan, 4Wayne State University School of Medicine, Department of Pathology, Detroit, Michigan, 5Soroka University Medical Center, Ben Gurion University, Department of Obstetrics and Gynecology, Beer-Sheva, Israel OBJECTIVE: Platelet activation has been implicated as a mechanism of disease in atherosclerosis and preeclampsia, which has led to the use of anti-platelet agents for the prevention of these diseases. This study was undertaken to determine whether premature labor (PTL) is associated with changes in the maternal plasma concentration of CD40 ligand (CD40L), a marker of platelet activation, which is elevated in atherosclerosis and preeclampsia. STUDY DESIGN: A cross-sectional study included the following groups: 1) nonpregnant (n⫽21); 2) normal pregnancy (n⫽71); and 3) PTL with intact membranes (n⫽136). Women in the PTL group were divided into 3 subgroups according to the presence or absence of intra-amniotic infection/inflammation (IAI) and preterm delivery: 3a) patients with PTL without IAI who delivered preterm (n⫽54); 3b) women with PTL and IAI (n⫽33); and 3c) women with PTL who delivered at term (n⫽49). Plasma concentrations of sCD40L were measured by ELISA. Nonparametric statistics were used for analysis. RESULTS: 1) Women with normal pregnancy had higher median maternal plasma sCD40L concentrations than non-pregnant women (p⫽0.017); 2) Patients with PTL had significantly higher median maternal plasma sCD40L concentrations than women with normal pregnancy regardless of the presence of IAI and gestational age at delivery (p⬍0.001; 3) Of interest, IAI was not associated with higher maternal plasma contractions of sCD40L. CONCLUSION: 1) Normal pregnancy is a state in which there is a physiologic increase of sCD40L, a marker of platelet activation. This observation is consistent with previous studies of platelet specific proteins; 2) Premature labor was associated with an increased maternal plasma sCD40L concentration. However, this increase could not be accounted by intrauterine infection/inflammation; 3) Our findings suggest that platelet activation occurs during an episode of preterm labor, and therefore, anti-platelet agents (dietary or pharmacologic) may play a role in the treatment or prevention of this condition. 0002-9378/$ - see front matter doi:10.1016/j.ajog.2007.10.134
0002-9378/$ - see front matter doi:10.1016/j.ajog.2007.10.132
Supplement to DECEMBER 2007 American Journal of Obstetrics & Gynecology
S47
www.AJOG.org 120
PROGESTERONE RECEPTOR GENE POLYMORPHISMS AND PREGNANCY-RELATED PARAMETERS IN A RACIALLY DIVERSE POPULATION DANIEL SKUPSKI1, IARA LINHARES2, NEIL NORMAND3, DEVRIM SEZEN2, OKSANA BABULA2, SHARI GELBER4, ANN MARIE BONGIOVANNI2, STEVEN S. WITKIN2, 1Cornell University, Flushing, New York, 2 Weill Medical College of Cornell University, Obstetrics and Gynecology, New York, New York, 3Cornell University Medical College, Obstetrics and Gynecology, New York, New York, 4Weill Medical College of Cornell University, Obstetrics and Gynecology, New York OBJECTIVE: The progesterone receptor (PR) exists in two isoforms, PR-A and PR-B. Both are products of the same gene and have different promoter sites. Progesterone binding to PR-B activates progesterone-responsive genes while binding to PR-A is without agonist activity and inhibits progesterone functions. A single G⬎A polymorphism at position ⫹331 in the PR gene results in increased production of PR-B, a decrease in the PR-A/PR-B ratio and has been associated with abnormal endometrial development. Since progesterone has diverse functions during gestation, we hypothesized that possession of the G⬎A polymorphism would influence pregnancy-related parameters. STUDY DESIGN: The borough of Queens has the most diverse racial/ethnic population in the United States. Buccal swabs were collected from 469 motherinfants pairs (2:1, term birth to preterm birth) and tested for the PR G⬎A polymorphism by gene amplification. Clinical and demographic parameters were collected and analyzed after completion of all laboratory testing. RESULTS: Maternal carriage of the variant A allele was identified in 5/53 (9.4%) White women, 9/111 (8.1%) Hispanics, 1/69 (1.4%) Blacks, 2/168 (1.2%) Asians and 0/58 East Indians (Ó2 for trend ⫽.0001). Only in Hispanic women was maternal allele A carriage associated with a higher median pre-pregnancy weight (75.2 kg vs. 63.0 kg, P ⫽ .048), as well as an elevated weight at delivery (95.9 kg vs. 79.7 kg, P ⫽ .002). Evaluating the population as a whole, maternal A allele carriage occurred almost equally in women with a term (10/286, 3.5%) or preterm (8/183, 4.4%) birth. However, among women who delivered preterm, the A allele was associated with a prior history of spontaneous preterm birth [(4/21 preterm, (19.0%) vs. 4/156 at term, (2.5%) (P ⫽ .007)]. CONCLUSION: The G⬎A PR polymorphism varies in frequency among different ethnic groups. Allele A carriage may influence maternal weight gain in Hispanic women and susceptibility to a repeat spontaneous preterm birth. Analysis of Hispanic women for this polymorphism may have clinical utility.
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0002-9378/$ - see front matter doi:10.1016/j.ajog.2007.10.131
121
CERVICAL FETAL FIBRONECTIN: AN INDEX OF INTRA-AMNIOTIC INFLAMMATION, HISTOLOGIC CHORIOAMNIONITIS AND IMPENDING PRETERM DELIVERY IN PATIENTS WITH PRETERM LABOR AND INTACT MEMBRANES JI HYUN KANG1, SI EUN LEE1, CHAN-WOOK PARK1, JONG KWAN JUN1, ROBERTO ROMERO2, BO HYUN YOON1, 1Seoul National University College of Medicine, Obstetrics and Gynecology, Seoul, South Korea, 2National Institute of Child Health & Human Development/National Institutes of Health/Department of Health & Human Services, Perinatology Research Branch, Detroit, Michigan OBJECTIVE: To determine if an elevated concentration of a cervical fetal fibronection (FFN) is a risk factor for amniotic fluid (AF) infection, AF inflammation, histologic chorioamnionitis and shorter amniocentesis-to-delivery interval in patients with preterm labor and intact membranes. STUDY DESIGN: Cervical FFN test was performed in 124 singleton pregnant women (ⱕ35 weeks of gestation) with preterm labor and intact membranes at the time of amniocentesis. AF was cultured for aerobic and anaerobic bacteria and for genital mycoplasmas. AF inflammation was defined as an elevated AF matrix metalloproteinase-8 (MMP-8) concentration (⬎23 ng/mL). Nonparametric tests and survival techniques were used for analysis. RESULTS: 1) Patients with an elevated FFN had a significantly lower gestational age at birth, shorter amniocentesis-to-delivery interval and higher median AF MMP-8 and higher rates of a positive AF culture, AF inflammation and spontaneous preterm delivery within 7 days and 2 weeks than those without an elevated FFN (p⬍.05 for each); 2) A FFN of ⱖ150 ng/mL had a better diagnostic performance in the identification of both AF inflammation and spontaneous preterm delivery than did a FFN of ⱖ50 ng/mL (p⬍.05 for specificity for each); 3) However, there was no significant relationship between an elevated FFN and histologic chorioamnionitis (p⬎.05); 4) Multivariate survival analysis indicated that both AF inflammation and a FFN of ⱖ150 ng/mL (but not ⱖ50 ng/mL) were associated with short latency periods (hazards ratio, 2.05 and 4.36; 95% confidence interval, 1.21-3.46 and 2.288.34, respectively; p⬍ .01). CONCLUSION: An elevated FFN was associated with short amniocentesis-todelivery interval and AF inflammation but not with histologic chorioamnionitis in patients with preterm labor and intact membranes. A FFN of ⱖ150 ng/mL had better diagnostic and prognostic performance than did a FFN of ⱖ50 ng/mL. 0002-9378/$ - see front matter doi:10.1016/j.ajog.2007.10.133
EXTREMES OF FETAL GROWTH ARE ASSOCIATED WITH SPONTANEOUS PRETERM BIRTH. RADEK BUKOWSKI1, FERGAL D. MALONE2, FLINT PORTER3, DAVID A. NYBERG4, CHRISTINE COMSTOCK5, GARY HANKINS1, KEITH EDDLEMAN6, SUSAN GROSS7, LORRAINE DUGOFF8, SABRINA D. CRAIGO9, ILAN E. TIMOR-TRITSCH10, STEPHEN R. CARR11, HONOR M. WOLFE12, MARY E. D’ALTON13, 1University of Texas Medical Branch, Obstetrics and Gynecology, Galveston, Texas, 2Royal College of Surgeons in Ireland, Obstetrics and Gynecology, Dublin, Ireland, 3University of Utah, Salt Lake City, Utah, 4The Fetal & Women’s Center of Arizona, OB/GYN Ultrasound, Scottsdale, Arizona, 5William Beaumont Hospital, Fetal Imaging Department, Royal Oak, Michigan, 6Mount Sinai Medical Center, Department of Obstetrics and Gynecology, New York, New York, 7Montefiore Medical Center/Albert Einstein College, OB-GYN and Women’s Health, Bronx, New York, 8University of Colorado Health Sciences Center, Ob/Gyn, Denver, Colorado, 9Tufts-New England Medical Center, Obstetrics and Gynecology, Boston, Massachusetts, 10NYU Medical Center, School of Medicine and Obstetrics & Gynecology, New York, New York, 11Women and Infants Hospital / Brown University, Maternal-Fetal Medicine, Providence, Rhode Island, 12University of North Carolina at Chapel Hill, Department of Obstetrics and Gynecology, Chapel Hill, North Carolina, 13Columbia University, OB/GYN Maternal Fetal Medicine, New York, New York OBJECTIVE: To determine the association between fetal growth and duration of pregnancy and incidence of preterm delivery. STUDY DESIGN: In a prospective cohort of 38,033 singleton pregnancies we estimated achieved percentiles of individual optimal birth weight – fetal growth potential (GP). Duration of pregnancy was estimated based on ultrasound measurement of crow-rump length between 10 4/7 and 13 6/7 weeks of pregnancy. Natural length of pregnancy was defined as gestational age at delivery in pregnancies uncomplicated by medical or obstetrical complications which may constitute indication for delivery. Pregnancies complicated by those conditions: congenital or chromosomal abnormalities, termination of pregnancy or stillbirth, chronic hypertension, pregnancy induced hypertension, preeclampsia, gestational and pre-gestational diabetes, placental abruption and placenta previa, were censored. The effects of GP ⬍10th and ⬎90th percentile on duration of pregnancy were evaluated using survival analysis-Cox regression. RESULTS: Comparing to normal growth (GP 10-90th percentile) GP ⬍10th but not GP ⬎90th percentile was associated with increased incidence of spontaneous preterm birth between 20 and 28 weeks (HR, 95% CI ⫽ 2.9, 1.5-5.8; p⫽0.002 and 0.7, 0.2-2.4; p⫽0.6, respectively). Both GP ⬍10th and GP ⬎90th percentile were associated with increased incidence of preterm birth between 28 and 34 weeks (HR, 95% CI ⫽ 2.9, 2.0-4.2; p⬍0.0001 and 2.1, 1.4-3.2; p⬍0.0001, respectively) and weaker associated with preterm birth between 34 and 37 weeks (HR, 95% CI ⫽ 1.3, 1.1-1.6; p⬍0.002 and 1.3, 1.1-1.5; p⬍0.01, respectively). At term, GP ⬍10th percentile was associated with significantly lower incidence of deliveries between 39 and 42 weeks (HR, 95% CI ⫽ 0.91, 0.87-0.96; p⫽0.001) while GP ⬎90th percentile with higher incidence of deliveries between 37 and 39 weeks (HR, 95% CI ⫽ 1.2, 1.1-1.3; p⬍0001) than normal growth. Proportional hazard assumption was met (p⬎0.05 for all). CONCLUSION: Both growth restriction and macrosomia are associated with early and late spontaneous preterm birth.
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IS PREMATURE LABOR A STATE OF PLATELET ACTIVATION? OFFER EREZ1, ROBERTO ROMERO1, DEBRA HOPPENSTEADT2, JAWED FAREED2, TINNAKORN CHAIWORAPONGSA3, JUAN PEDRO KUSANOVIC1, SHALI MAZAKI-TOVI3, FRANCESCA GOTSCH1, NANDOR GABOR THAN1, EDI VAISBUCH1, CHONG JAI KIM4, JIMMY ESPINOZA3, POOJA MITTAL3, CHIA-LING NHAN-CHANG3, NEIL HAMILL3, MOSHE MAZOR5, SONIA HASSAN3, 1Perinatology Research Branch, NICHD, NIH, DHHS, Detroit, Michigan, 2Loyola University Health System, Department of Pathology, Chicago, Illinois, 3 Wayne State University School of Medicine, Department of Obstetrics and Gynecology, Detroit, Michigan, 4Wayne State University School of Medicine, Department of Pathology, Detroit, Michigan, 5Soroka University Medical Center, Ben Gurion University, Department of Obstetrics and Gynecology, Beer-Sheva, Israel OBJECTIVE: Platelet activation has been implicated as a mechanism of disease in atherosclerosis and preeclampsia, which has led to the use of anti-platelet agents for the prevention of these diseases. This study was undertaken to determine whether premature labor (PTL) is associated with changes in the maternal plasma concentration of CD40 ligand (CD40L), a marker of platelet activation, which is elevated in atherosclerosis and preeclampsia. STUDY DESIGN: A cross-sectional study included the following groups: 1) nonpregnant (n⫽21); 2) normal pregnancy (n⫽71); and 3) PTL with intact membranes (n⫽136). Women in the PTL group were divided into 3 subgroups according to the presence or absence of intra-amniotic infection/inflammation (IAI) and preterm delivery: 3a) patients with PTL without IAI who delivered preterm (n⫽54); 3b) women with PTL and IAI (n⫽33); and 3c) women with PTL who delivered at term (n⫽49). Plasma concentrations of sCD40L were measured by ELISA. Nonparametric statistics were used for analysis. RESULTS: 1) Women with normal pregnancy had higher median maternal plasma sCD40L concentrations than non-pregnant women (p⫽0.017); 2) Patients with PTL had significantly higher median maternal plasma sCD40L concentrations than women with normal pregnancy regardless of the presence of IAI and gestational age at delivery (p⬍0.001; 3) Of interest, IAI was not associated with higher maternal plasma contractions of sCD40L. CONCLUSION: 1) Normal pregnancy is a state in which there is a physiologic increase of sCD40L, a marker of platelet activation. This observation is consistent with previous studies of platelet specific proteins; 2) Premature labor was associated with an increased maternal plasma sCD40L concentration. However, this increase could not be accounted by intrauterine infection/inflammation; 3) Our findings suggest that platelet activation occurs during an episode of preterm labor, and therefore, anti-platelet agents (dietary or pharmacologic) may play a role in the treatment or prevention of this condition. 0002-9378/$ - see front matter doi:10.1016/j.ajog.2007.10.134
0002-9378/$ - see front matter doi:10.1016/j.ajog.2007.10.132
Supplement to DECEMBER 2007 American Journal of Obstetrics & Gynecology
S47