Early ultrasound for fetal anatomy in the obese pregnant woman

S66 SMFM Abstracts 186 PRIMARY PREVENTION OF PREMATURITY MEDIATED BY GENITAL INFECTION/ INFLAMMATION: CRITICAL FACTORS ASSOCIATED WITH IMPROVED OUTCOMES JAMES MCGREGOR1, JANICE FRENCH2, OZLEM EQUILS3, 1University of Southern California, Obstetrics/Gynecology, Los Angeles, California, 2Los Angeles Best Baby Network, Santa Monica, California, 3University of California at Los Angeles, Pediatrics, Los Angeles, California OBJECTIVE: Examine selected, prospective controlled trials for factors associated with successful primary prevention of preterm birth (PTB) mediated by ascending reproductive tract infection/inflammation (RTI) and/or BV. Background: Second trimester, late miscarriage (LM), and !35 week PTB are etiologically associated with RTIs and other potentially remediable conditions. However, timing, treatments, and populations likely to benefit require clarification. STUDY DESIGN: Controlled trials among asymptomatic women which evaluated PTB and related outcomes were analyzed. Study design and factors were evaluated for positive/negative effects. RESULTS: Ten studies met evaluation criteria. Four critical factors associated with .50 reduction in PTB were identified: A) Early (!20 weeks) screening and treatment (including test of cure [TOC]) of affected mothers (BV, STIs) (4/4). B) Clindamycin (oral or topical) treatment for BV when given early in gestation (3/3). C) Comprehensive ‘‘screen and treat’’ Study designs in which prevalent RTIs were systematically identified and treated beginning !20 weeks gestation (3/3). D) Relevent genotypic/phenotypic-environment interactions are more common among African-American and black women of differing racial and geographic origins. Benefits of treatment are largest in populations at increased risk and late treatments are ineffective. CONCLUSION: Controlled trials evaluating primary prevention of prematurity !35 weeks and/or LM demonstrated consistent, biologically plausible and clinically applicable determinants associated with reduced prematurity !34 weeks. 1) Early gestation screening and treatment followed by TOC; 2) Use of clindamycin for treatment of BV early in pregnancy; 3) Comprehensive screening and treatment of prevalent RTIs and BV. African-American and other black women demonstrate differential benefits compared to comparator women. These findings can inform research design and medical care strategies designed to prevent PTB/pPROM etiologically linked to infection/inflammation. 0002-9378/$ - see front matter doi:10.1016/j.ajog.2006.10.205

188 EARLY ULTRASOUND FOR FETAL ANATOMY IN THE OBESE PREGNANT WOMAN ALYSSA MILLS1, BRITA BOYD1, BARBARA HERTZBERG2, HAYWOOD BROWN1, GEETA K. SWAMY1, 1Duke University, Obstetrics & Gynecology, Durham, North Carolina, 2Duke University, Radiology, Durham, North Carolina OBJECTIVE: To determine whether early transabdominal (TA) plus transvaginal (TV) ultrasound (US) can optimize standard fetal anatomic survey and can be performed in a shorter amount of time. STUDY DESIGN: In this prospective, observational pilot study, 20 obese (BMI R30 kg/m2) pregnant women underwent US for fetal anatomy at 14-16 wks (US1) and again at 18-20 wks (US2). TV & TA imaging were performed to complete US1. Images were independently reviewed by 3 physicians and individual structures were described as not visualized (0 points), suboptimally visualized (1 point), or optimally visualized (2 points). Points were added for a perfect score of 6/structure, 126/US overall. Kappa statistics were used to assess inter-reviewer agreement. Paired t-test was used to compare scores, p!.05 significant. RESULTS: Mean BMI at US1 was 40.5 kg/m2. Both US took similar time to complete (mean 35 minutes for US1, 37 for US2, p=0.6). Inter-reviewer agreement ranged .12-.78. Cardiac anatomy and kidneys were equally wellvisualized at both US; however other structures were more often optimally visualized at US2. Overall, US2 performed better than US1. CONCLUSION: Early US in obese women was useful for some structures, but should not replace US at 18-20 wks.

Structure

Kappa (range)

Mean score at US1

Mean score at US2

p

cerebellum Lateral ventricle Cavum septi pellucidi 4 chamber heart LVOT Short-axis heart Kidneys L spine S spine Total

1 .64 .12-.44 .55-.74 .55-.78 .7-.8 .35-1 .58-.69 .58-.69 N/A

4.4 4.7 4.1 4.4 3.7 3 5.3 4.2 4 97

5.9 5.9 5.4 5 4.7 4.0 5.7 5.3 5.3 110

.004 .03 .03 NS NS NS NS .02 .004 .009

0002-9378/$ - see front matter doi:10.1016/j.ajog.2006.10.207 187 THE IMPACT OF PRETERM BIRTH IN TWIN PREGNANCY ON SUBSEQUENT SINGLETON PREGNANCY OUTCOMES AMY MERLINO1, BRIAN MERCER1, 1CASEMetroHealth Medical Center, Reproductive Biology, Cleveland, Ohio OBJECTIVE: Preterm birth (PTB) in singleton gestations is a risk factor for PTB in future pregnancies. Twin pregnancies are also at high risk for PTB. It is generally believed that PTB in twin pregnancies does not predict a similar outcome in a subsequent singleton pregnancy. Our goal was to evaluate the impact of adverse outcomes, specifically PTB, spontaneous preterm birth (SPB) and early spontaneous preterm birth (EPB: !34 weeks) in a penultimate twin gestation on similar outcomes in the subsequent singleton pregnancy. STUDY DESIGN: We identified all women who delivered consecutively a twin followed by a singleton pregnancy at our institution from 1974-2004. Those with an intervening pregnancy delivering after 20 weeks were excluded. Individual chart review confirmed obstetric history, gestational age of and indications for all PTBs. The occurrence of PTB, SPB and EPB in the twin gestation was correlated to outcomes in the singleton pregnancy. p!0.05 was considered significant. RESULTS: 324 women met inclusion criteria. 61.7% of twin pregnancies delivered preterm vs 17.0% of singleton pregnancies (p!0.0001). PTB in the twin pregnancy increased a woman´s risk for PTB in the subsequent singleton pregnancy (23 vs 7.3% for twins at term, RR:3.17 [1.7-5.9], p=0.002). Women with twin SPB were at increased risk for subsequent singleton SPB (22.1% vs 6.9% for twins without SPB, RR: 3.51[1.9-6.6], p=0.0002). The risk of subsequent singleton SPB increased with decreasing gestational age at delivery of the twin pregnancy (24.7 vs 16.4 vs 6.9% for EPB, SPB at 34-36 weeks and no SPB, p=0.0005). The impact of SPB in twin gestations on subsequent singleton pregnancy outcomes persisted after controlling for antecedent term birth or SPB before the twin pregnancy (p!0.02). CONCLUSION: Contrary to general belief, PTB in a twin pregnancy is associated with an increased risk of preterm birth in a subsequent singleton pregnancy. This correlation is stronger with early preterm twin birth. Prior twin pregnancy outcome should be used in counseling women with subsequent singleton pregnancies. 0002-9378/$ - see front matter doi:10.1016/j.ajog.2006.10.206

189 CHLORHEXIDINE WASHING OF THE VAGINA IN LABOR EFFECTIVELY REDUCES BACTERIAL COLONIZATION: A STUDY BY THE GLOBAL NETWORK FOR PERINATAL & REPRODUCTIVE HEALTH VELDA MUSHANGWE1, JORGE E. TOLOSA2, LEONARDO PEREIRA2, ALEXIO MASHU1, SHRIKANT BANGDIWALA3, SIMBARASHE RUSAKANIKO4, PISAKE LUMBIGANON5, SIMON MADZIME1, OFFICE CHIDEDE6, LOVEMORE GWANZURA7, GARY L. DARMSTADT8, TSUNGAI CHIPATO1, 1University of Zimbabwe, Obstetrics & Gynecology, Harare, Zimbabwe, 2Oregon Health & Science University, Global Network for Perinatal & Reproductive Health, Obstetrics and Gynecology, Portland, Oregon, 3University of North Carolina at Chapel Hill, Biostatistics, Chapel Hill, North Carolina, 4University of Zimbabwe, Community Health, Harare, Zimbabwe, 5Khon Kaen University, Obstetrics & Gynecology, Khon Kaen, Thailand, 6University of Zimbabwe, Pediatrics, Harare, Zimbabwe, 7University of Zimbabwe, Harare, Zimbabwe, 8Johns Hopkins University, International Health, Baltimore, Maryland OBJECTIVE: To determine if serial vaginal washing (VW) with chlorhexidine (CHX) at 1% reduces vaginal bacterial colonization in labor. STUDY DESIGN: Observational longitudinal study of bacterial growth (BG) from serial vaginal swabs (VS) obtained during labor, as part of a RCT testing the use of vaginal and neonatal washing with CHX to reduce neonatal infection in Harare, Zimbabwe. After IRB approval, written informed consent and sampling by convenience, women (n=37) were enrolled. 32 women received CHX washings at 1% q 2 hrs; 5 women were controls (CNT) and received usual care. A high VS was obtained before each VW was done with a gloved hand holding a 4 ! 4 cm cotton ball with G20 cc of CHX; culture on 5% trypticase soy in sheep blood agar, incubated 48 hr at 37(C. BG was defined: heavy 3C, moderate 2C, light 1C, no 0 (NG). 9 women in the CHX and 1 in the CNT had NG at the first swab and were excluded from analysis, leaving n=23 (CHX) and 4 (CNT) for analysis. Change in BG from initial count to NG was compared after 1 and 2 or more VW or the last swab before delivery. RESULTS: Of 23 women who had CHX washings 13 showed a clinically significant change in BG from their initial culture to NG after 1 vaginal wash (56.5%). 1/23 showed no change after 1 wash before delivery. 6/9 of the remaining women showed NG after 2 vaginal washes. 3/9 showed a reduction in BG after 2 washes. Overall, in 19/22 women who remaned pregnant there was NG after a second vaginal wash (86.4%). In the CNT group there was no clinically significant reduction in BG during labor. The intervention was well accepted by patients and staff. The most common bacteria identified were: E. coli 7/27 (26 %), S. aureus 5/ 27, Group D Streptococcus 5/27, Coag negative Staphylococcus 4/27, Klebsiella spp. 2/27, Group B Streptococcus 2/27, others 2/27. CONCLUSION: Vaginal washing with 1% CHX effectively reduced vaginal bacterial colonization in labor. This safe and inexpensive intervention could reduce neonatal bacterial colonization and possibly neonatal morbidity and mortality. 0002-9378/$ - see front matter doi:10.1016/j.ajog.2006.10.208