founders. In twin pregnancies, bleeding was not significantly associ-ated with any of the perinatal outcomes analyzed.CONCLUSION: In twins there is no significant association between first-trimester bleeding and adverse perinatal outcomes. In singletons therisk of pregnancy complications is increased.

140 Effects of low pre-pregnancy body mass index andgestational weight gain on neonatal outcomesMilana Berguig1, Julia Timofeev2, Helain Landy1

1MedStar Georgetown University Hospital, Obstetrics and Gynecology,Washington, DC, 2MedStar Washington Hospital Center, Obstetrics andGynecology, Washington, DCOBJECTIVE: To evaluate the effect of low pre-pregnancy body massindex (BMI) and low gestational weight gain on neonatal outcomes ascompared to parturients with normal BMI and normal or excessiveweight gain.STUDY DESIGN: A retrospective review of a multicenter cohort of de-identified data in the Consortium on Safe Labor (NICHD). This da-tabase includes information on 233,844 births from 228,668 deliveriesfrom 2002-2008. Maternal factors and neonatal outcomes were ana-lyzed by BMI (low BMI �18.5 kg/m2, normal 18.5-24.9 kg/m2) andweight gain during gestation as recommended by the Institute ofMedicine 2009 guidelines (normal weight gain of 28-40lbs for womenwith low BMI, and 25-35lbs for women with normal BMI). Chi squareand Fisher’s exact tests were used for statistical analysis, with signifi-cance determined at two-tailed ��0.05.RESULTS: Low pre-pregnancy BMI showed statistically significant in-creases in the risk of small for gestational age (SGA) infants (OR �1.96, CI � 1.93 - 2.00), NICU admission (OR � 1.24, CI � 1.21 -1.26), and neonatal death (OR � 1.62, CI � 1.47 - 1.79). No statisti-cally significant differences were seen in gestational age at delivery orneed for newborn resuscitation. When considering recommendedweight gain, women who gained less weight (�28 lbs for low BMI, and�25 lbs for normal BMI) had higher risks of poor pregnancy out-comes (SGA, 5-minute Apgar score � 7, NICU admission, antepar-tum and intrapartum stillbirth (Table).CONCLUSION: Pregnancy outcomes are influenced by both pre-preg-nancy BMI and weight gain during pregnancy. These findings suggestthat women can minimize their risk of neonatal morbidity and mor-tality by optimizing their weight prior to conception and gaining therecommended weight amount throughout the pregnancy.

141 Protective and high risk genotypes mediate therisk for preterm birth in smokersMolly Stout1, Heather Frey1, Methodius Tuuli1, Alison Cahill1,Anthony Odibo1, Jenifer Allsworth1, George Macones1

1Washington University in St. Louis, Obstetrics and Gynecology, St. Louis,MOOBJECTIVE: Smoking during pregnancy is associated with adverse ob-stetric outcomes, in part via vasculo-toxic effects of cigarette expo-sure. We investigated whether single nucleotide polymorphisms(SNPs) in vascular regulatory genes (vascular endothelial growth fac-tor VEGF and a VEGF receptor fms-like tyrosine kinase FLT) affectthe risk for preterm birth (PTB) in smokers.STUDY DESIGN: A secondary analysis of singleton pregnancies enrolledin a multicenter randomized control trial investigating the associationbetween periodontal disease and PTB. One group of women withoutperiodontal disease was enrolled as an observational group for geno-

typing studies and was the population for this study. Buccal swabswere used for SNP genotyping. SNPs for VEGF and FLT were identi-fied from dbSNP, Bio-Carta, and KEGG. Smoking status was definedas current smoking during the pregnancy. Due to SNP variation byrace only Black women were included in this analysis. Univariableanalysis was performed to assess the association between vascularSNPs and PTB, and smoking and PTB. Multivariable regression wasused to test for interactions between vascular SNPs and smoking forthe risk of PTB.RESULTS: Of 932 Black women with smoking and SNP data, 15% de-livered �37 weeks, 6% delivered �34 weeks and 13% were currentsmokers. Twenty-two VEGF and 128 FLT SNPs were investigated forassociation with smoking and PTB. Two VEGF variants rs833060 andrs3025035 demonstrated a statistically significant interaction withsmoking and PTB, with an increased risk for PTB in smokers and noincreased risk in nonsmokers. Five FLT SNPs demonstrated a similarinteraction for increased PTB in smokers, whereas one variantrs1324058 demonstrated a protective effect (Table).CONCLUSION: In a population of Black women, the risk for PTB inpatients who smoke is likely mediated by the genotypes of SNPs inimportant vascular genes. These data provide evidence for geneticallysusceptible or protective genotypes mediating the effects environ-mental exposures on the risk for PTB.

142 Human leukocyte antigen-g tissue expression at thematernal fetal interface is increased in preterm birthMolly Stout1, D. Michael Nelson1, George Macones1,Indira Mysorekar1

1Washington University in St. Louis, Obstetrics and Gynecology, Saint Louis,MOOBJECTIVE: Human leukocyte antigen-G (HLAG) is a major histo-compatibility complex protein expressed on extravillous trophoblastcells. HLAG functions to down-regulate maternal immune responseas non-self fetal cells invade maternal uterine tissue. We tested thehypothesis that HLAG tissue expression at the maternal-fetal interface(basal plate) of human placentas is altered in preterm birth (PTB).

Neonatal outcomes by weight gain

Poster Session I Clinical Obstetrics, Epidemiology, Fetus, Medical-Surgical Complications, Neonatology, Physiology/Endocrinology, Prematurity www.AJOG.org

S72 American Journal of Obstetrics & Gynecology Supplement to JANUARY 2013

STUDY DESIGN: A nested case control study within a prospective cohortinvestigating infection related pathways for PTB. Demographics,medical history and pregnancy outcomes were collected prospec-tively. Women with PTB were compared to those who delivered atterm. Basal plate tissue was paraffin embedded. Immunohistochem-ical expression of HLAG positive cells was quantified using digitalbrightfield microscopy. Basal plate tissue % surface area positive forHLAG was considered both as a continuous and dichotomous (highHLAG defined as �75th percentile) variable. Univariable, bivariable,and multivariable regression were used to test the association betweenHLAG expression and PTB.RESULTS: Of 135 pregnancies, 32.6% delivered �37 weeks. Of these,79.6% were spontaneous. Basal plate HLAG positivity was signifi-cantly increased in PTB compared to term birth (36.6% vs. 32.6%,p�0.01). HLAG tissue positivity remained higher when the analysiswas restricted to spontaneous labor (Table). When comparing pa-tients with and without labor there was no difference in HLAG posi-tivity (33.8% vs. 33.9%, p�0.9) suggesting that the differences notedare not due to the labor process alone. High HLAG (defined as �75thpercentile) was associated with an 8-fold increased risk for PTB (aOR8.9, 95%CI 2.0-38.5, p�0.01) after controlling for steroid administra-tion and prior PTB.CONCLUSION: Increased HLAG tissue expression at the maternal fetalinterface of human placentas is associated with spontaneous PTB. Wespeculate that HLAG may alter immunotolerance and mediate therole of infection and inflammation in the pathogenesis of PTB.

143 Is there a role for cerclage in twin gestation with shortcervical length (CL)? Single center experienceNatallie Stoval1, Baha Sibai2, Mounira Habli1

1Good Samritan Hospital, Obstterics, Cincinnati, OH, 2University of TexasHoustonl, Obstetrics, Houston, TXOBJECTIVE: A recent meta-analysis of 49 twins with short cervix andcerclage showed a significant doubling in incidence of preterm deliv-ery(PTD) as compared to no cerclage, but statistically similar perina-tal mortality among groups .Our aim in this large, single center casecontrol study is to compare pregnancy outcome between women re-ceiving cerclage vs. no cerclage in twin pregnancies with ultrasoundevidence of short CL� 25 mm.STUDY DESIGN: A retrospective study of 105 diamniotic twin pregnan-cies with CL� 25mm between 16-24 weeks(wks) of gestation(GA): 54received cerclage and 61 served as control. Exclusion criteria includedchromosomal or congenital malformations and twin to twin transfu-sion syndrome. Primary outcome was rate of PTD at � 34 wks. Sec-

ondary outcomes were maternal demographics, obstetric outcome asrate of premature rupture of membranes (PROM), GA at delivery,pregnancy loss at �24 wks and neonatal outcome.RESULTS: As compared to control, cases had no significant differencein baseline characteristics (table). Mean GA at cerclage placement was20.4 �2.3 wks. In those receiving cerclage,there was significant in-crease in CL as compared pre to post cerlcage (13.73� 6.9 vs. 27.0�8.3 mm, p�0.05). As compared to controls, cases had a significantlylower rate of preterm labor admissions and acute tocolysis but signif-icantly higher rate of PPROM (39% vs. 20%,p�0.038). There were nosignificant difference among groups in regard to primary outcomeand neonatal outcome. When data were analyzed according to CL �15mm vs. �15mm there was no significant difference in outcomedata.CONCLUSION: We found that performance of cerclage in twin pregnan-cies with short CL does not reduce rate of PTD. In addition, contraryto results of metaanlaysis it did not increase composite neonatal mor-bidity. Thus, there is a need for a multicenter randomized trial toanswer the potential benefits/risks of cerclage in twins with short CL.

144 Understanding the decision to breastfeed:a survey of postpartum mothersNicole Rankins1, Lucy Rice1, Gretchen Brayman1,Suneet Chauhan1

1Eastern Virginia Medical School, Obstetrics and Gynecology, Norfolk, VAOBJECTIVE: To assess breastfeeding intentions, beliefs, and knowledgethrough survey of mothers postpartum.STUDY DESIGN: A 24 question anonymous survey was administered toeligible mothers from June to August 2011 during their postpartumhospitalization at an urban medical school. Univariate analysis in-cluded frequencies with percentages or mean (central tendency) withstandard deviation (variation) as appropriate. Bivariate comparisonsof continuous variables with breastfeeding plans were completed us-ing t-test. Bivariate comparisons of categorical variables with breast-feeding plans were done utilizing Chi-square test. P � 0.05 was con-sidered statistically significant.RESULTS: There were 344 eligible participants. The response rate was59% (N�202). Overall, 69% (N�135) planned to breastfeed beforecoming to the hospital and among them 94% (N�127) planned tobreastfeed at discharge. Only 6% (N�8) who did not plan to breast-feed prior to coming to the hospital planned to breastfeed at dis-charge. Almost half planned to breastfeed for � 6 months (48%).Those with a family member who breastfed were more likely to breast-feed than those without (63% vs. 48%, p�0.001). If the partner sup-ported breastfeeding (N�114), 94% of those mothers planned tobreastfeed, whereas if the partner did not support breastfeeding(N�30), 97% of those mothers did not plan to breastfeed (p�0.001).Gravidity, hours worked/week, attending a breastfeeding class, or re-ceiving information prenatally from a healthcare provider did notdiffer between those who planned to breastfeed and those who didnot. The most common reason (65%) for not breastfeeding was “I did

Left, IHC of preterm placenta; Right, Digital microscopy of same image.

*After adjusting for corticosteroid administration and bacterial vaginosis.

www.AJOG.org Clinical Obstetrics, Epidemiology, Fetus, Medical-Surgical Complications, Neonatology, Physiology/Endocrinology, Prematurity Poster Session I

Supplement to JANUARY 2013 American Journal of Obstetrics & Gynecology S73