S180 SMFM Abstracts 634 NEONATAL OUTCOMES AT THE THRESHOLD OF VIABILITY ISAIAH JOHNSON1, MATTHEW SAXONHOUSE2, RODNEY EDWARDS1, 1University of Florida, Obstetrics and Gynecology, Gainesville, Florida, 2University of Florida, Pediatrics, Gainesville, Florida OBJECTIVE: To estimate survival and intact survival of infants based on best obstetric estimate of gestational age (GA) and ultrasound estimate of fetal weight (EFW). STUDY DESIGN: We performed a retrospective cohort analysis of all deliveries at Shands Hospital at the University of Florida from 01/99-12/03. Mother-infant pairs were included if delivery occurred at 23-26 weeks GA or EFW less than 1000 g. Exclusion criteria were: either the medical staff or the pregnant considered the fetus non-viable prior to delivery, no timely delivery for fetal indications, multiple gestation, congenital anomalies or ‘‘TORCH’’ infection, chromosomal abnormality or genetic syndrome, or EFW not done within 7 days of delivery. Survival was defined as being alive at hospital discharge. ‘‘Intact’’ survival signified the absence of all of the following: oxygen requirement at O36 weeks corrected GA, grade III or IV intraventricular hemorrhage, periventricular leukomalacia, retinopathy of prematurity requiring laser treatment, necrotizing enterocolitis requiring surgical intervention, or evidence of hearing dysfunction. RESULTS: There were 112 mother-infant pairs included. Overall and intact survival stratified by GA and EFW are presented in the tables [n (%; 95% CI)]. The only infant surviving at 23 weeks and the only infant with intact survival less than 25 weeks had birth weights over 700 g. CONCLUSION: Even with timely delivery for fetal indications, intact survival is infrequent with either GA !25 weeks or EFW !700g. GA
N
Survival
23 24 25 26
8 24 30 31
1 12 20 28
(13%; (50%; (67%; (90%;
EFW
N
Survival
400-499 500-599 600-699 700-799 800-899 900-999
5 15 21 27 23 14
1 6 11 23 18 13
636 DECLINE OF OPERATIVE VAGINAL DELIVERIES IN THE UNITED STATES: IMPACT ON SEVERE PERINEAL LACERATIONS HEATHER S. LIPKIND (F)1, RAY AARONS2, LYNN L. SIMPSON1, 1Columbia University, Maternal Fetal Medicine, New York, New York, 2Columbia University, Mailman School of Public Health, New York, New York OBJECTIVE: To determine trends of operative vaginal deliveries over the past decade and to examine the effect to which those trends have affected the associated odds of 3rd and 4th degree perineal lacerations. STUDY DESIGN: A large population-based retrospective cohort study using data from the National Hospital Discharge Summary Survey (1990- 2001) that involved sampling from non-federal short stay hospitals in the United States (5,026,192 births) was performed. Temporal trends in forceps and vacuum deliveries were examined. The magnitude of the associated risk of 3rd and 4th degree perineal lacerations were quantified using the odds ratio (OR) with 95% confidence intervals (CI). RESULTS: During the 11 year study period, the rate of forceps procedures decreased by 65% from 6.4% to 2.4% of all deliveries. The total number of vacuum deliveries increased from 4.7% to 5.9% of all deliveries. With the decline in the total number of forceps deliveries, the odds of a severe perineal laceration associated with forceps increased from an OR of 6.9 (95% CI:6.17.9) to an OR of 9.8 (95% CI:8.4-11.6). The odds of a severe laceration associated with vacuum deliveries also increased from an OR of 4.1 (95% CI:3.5-4.7) to an OR of 5.2 (95% CI:4.5-5.9).
Intact survival 0.3, 50) 32, 69) 49, 81) 74, 98)
(20%; (40%; (52%, (85%; (78%; (93%;
0 1 8 13
(0%; 0, 38) (4%; 0, 22) (27%; 14, 45) (42%; 27, 59)
Intact survival 2, 65) 20, 65) 33, 72) 67, 95) 58, 91) 67, 100)
0 1 1 10 5 6
(0%; 0, 50) (7%; 0, 32) (5%; 0, 25) (37%; 22, 56) (22%; 9, 43) (43%; 22, 68)
635 CHARACTERISTIC INTRAPARTUM FETAL HEART RATE PATTERNS IN NEONATES WITH ASPHYXIATION- AND NON-ASPHYXIATION-RELATED CEREBRAL PALSY YUKI KODAMA (F)1, TOMOAKI IKEDA2, HIROSHI SAMESHIMA3, TSUYOMU IKENOUE4, 1Miyazaki University, Obstetrics and Gynecology, Kiyotake-cho, Miyazaki, Japan, 2Miyazaki Medical College, Kiyotake, Miyazaki, Japan, 3 University of Miyazaki, Kiyotake-cho, Miyazaki, Japan, 4Miyazaki Medical College, Miyazaki, Japan OBJECTIVE: Studies attempting to correlate intrapartum fetal heart rate (FHR) patterns with the subsequent development of cerebral palsy (CP) have reported controversial results. In this prospective study, we evaluated neonates at high risk for developing CP, differentiated CP caused by asphyxia from that not caused by asphyxia, and correlated the FHR patterns with predictions of CP. STUDY DESIGN: From 1998 to 2003, 134 infants were registered as having a high risk for CP out of 65,197 live births in Miyazaki Prefecture, Japan. A risk of asphyxia-induced CP was defined if infants fulfilled MacLennanA˚fs (1999) categories. Otherwise, we categorized them as having a risk of nonasphyxiarelated CP. These categories were applied to infants born at 34 weeks of gestational age or greater; 48 were included in the study and intrapartum FHR patterns were measured. FHR patterns were interpreted according to the 1997 NICHD guidelines. RESULTS: Fifteen of the neonates were categorized for asphyxia and 33 were non-asphyxia. After a one-year follow-up, 13 infants with asphyxia and 28 without asphyxia were diagnosed with CP. All 13 infants with asphyxiarelated CP had shown bradycardia, with a FHR nadir of less than 90 bpm and a duration of more than 13 min. In 28 infants with nonasphyxia-related CP, 20 (71%) had shown a nonreassuring FHR pattern in the intrapartum period: 11 had prolonged FHR deceleration or bradycardia; eight had recurrent late or severely variable deceleration and one showed other symptoms. CONCLUSION: Significant bradycardia was a characteristic FHR pattern in infants who developed CP caused by asphyxia. It is important to differentiate nonasphyxia-related CP from asphyxia-related CP, because 71% of the neonates showed a nonreassuring FHR pattern, which could be used legally as evidence of asphyxia.
Procedures and the odds of 3rd and 4th degree lacerations per year CONCLUSION: There has been a sharp decrease in the number of forceps deliveries performed over the past decade that has been associated with an increase in risk of severe perineal injuries.
637 WOMEN DELIVERING IN PRIVATE HOSPITALS IN NEW YORK CITY HAVE AN INCREASED RISK OF PRIMARY CESAREAN DELIVERY DEPENDING ON THEIR SOCIOECONOMIC STATUS HEATHER S. LIPKIND (F)1, TERRY J. ROSENBERG2, MARY ANN CHIASSON3, 1Columbia University, Maternal Fetal Medicine, New York, New York, 2Medical and Health Research Association of NYC, New York, New York, 3Columbia University, Mailman School of Public Health, New York, New York OBJECTIVE: To evaluate the primary cesarean delivery risk by payer and hospital type in New York City (NYC). STUDY DESIGN: Data were collected from the 2001-2003 New York City birth files for 146,271 singleton nulliparous women delivering beyond 24 weeks gestation. Logistic regression was performed to estimate the odds of a primary cesarean delivery among patients with Medicaid versus patients who were privately insured, The analysis was stratified by hospital type (public vs private) and adjusted for race/ethnicity, maternal age, maternal education, gestational age at delivery, birth weight, a composite pregnancy related complications variable, and pre-pregnancy maternal weight. RESULTS: The overall primary cesarean rate in private not for profit hospitals was 26.4 % and was 20.4% in public hospitals. In private hospitals, patients with private insurance have 1.5 times the odds of primary cesarean section compared to Medicaid patients (table 1). In city hospitals, patients with private insurance did not have an increased risk of cesarean delivery compared to Medicaid patients. When the odds ratios were adjusted, the results remained significant. CONCLUSION: In private NYC hospitals, there is a higher risk of Cesarean section in privately insured patients compared to those with Medicaid. This difference is not seen in public hospitals. Odds ratios and 95% confidence intervals for primary cesarean delivery stratified by hospital type: Private insurance versus Medicaid Private Hospital N = 118231 Crude OR
Adjusted OR
Private insurance (n = 72024) Medicaid (n = 46207)
OR (95%CI) 1.47 (1.43,1.51) d 1.20 (1.15,1.24)
Public Hospital N = 28040 Private insurance (n = 27777) Medicaid (n = 263)
OR (95%CI) 0.87 (0.64,1.92) d 0.79 (0.58,1.10)