Overview of spontaneous preterm birth: a complex and multifactorial phenotype.

The phenotype of spontaneous preterm birth (SPTB) refers to the biochemical and physical characteristics present at the time of preterm delivery. These are the result of the processes that cause this complication. The lack of understanding about the etiologies and our inability to prevent SPTB are because of the complex nature and multiple processes responsible for maintenance of pregnancy and the transition to labor. Any of these processes, when activated prematurely, may lead to SPTB. This article provides an overview of the SPTB phenotype, which may assist with future attempts to reduce in the incidence of SPTB.

Association of cord blood digitalis-like factor and necrotizing enterocolitis.

OBJECTIVE: Endogenous digoxin-like factor (EDLF) has been linked to vasoconstriction, altered membrane transport, and apoptosis. Our objective was to determine whether increased EDLF in the cord sera of preterm infants was associated with an increased incidence of necrotizing enterocolitis (NEC). STUDY DESIGN: Cord sera from pregnant women enrolled in a randomized trial of MgSO4 for fetal neuroprotection were analyzed for EDLF using a red cell Rb(+) uptake assay in which the inhibition of sodium pump-mediated Rb(+) transport was used as a functional assay of EDLF. Specimens were assayed blinded to neonatal outcome. Cases (NEC, n = 25) and controls (neonates not developing stage 2 or 3 NEC, n = 24) were matched by study center and gestational age. None of the women had preeclampsia. Cases and controls were compared using the Wilcoxon test for continuous and the Fisher exact test for categorical variables. A conditional logistic regression analysis was used to assess the odds of case vs control by EDLF level. RESULTS: Cases and controls were not significantly different for gestational age, race, maternal steroid use, premature rupture of membranes, or MgSO4 treatment. In logistic models adjusted for treatment group, race, premature rupture of membranes, and gestational age, cord sera EDLF was significantly associated with development of NEC (P = .023). CONCLUSION: These data demonstrated an association between cord sera EDLF and NEC.

Estimating recurrence of spontaneous preterm delivery.

OBJECTIVE: To identify factors associated with spontaneous preterm birth and to estimate the risk of its recurrence for the second through fourth births among women in Utah who had a first and any subsequent birth between 1989 and 2001, using a retrospective cohort study design. METHODS: Utah state birth records were reviewed to identify women with a first live birth and at least one subsequent live birth from 1989 to 2001. Recurrence risks for spontaneous preterm birth were calculated for first through fourth births. Then all parties (1-12) and multiple maternal risk factors were used to estimate recurrence risks for pre-term birth outcomes by multinomial regression. Recurrence risks for early and late spontaneous preterm birth were calculated. Recurrence also was evaluated as the fraction attributable to previous spontaneous preterm birth. Using the identified factors, the sample was divided and the model was estimated for a subset of births (1989-1999); its predictive value was tested on the remaining births (2000-2001). RESULTS: Women who experienced a spontaneous preterm birth before 34 weeks of gestation in their first or second live birth had the highest rate of recurrence. Spontaneous preterm birth before 34 weeks was the highest risk factor for recurrence of early spontaneous preterm birth (relative risk 13.56, 95% confidence interval 11.5-16.0), and, in general, risks were highest for recurrences of same gestational age outcomes. CONCLUSION: A history of a live spontaneous birth before 34 weeks of gestation is a strong predictor of subsequent spontaneous preterm birth. A model of clinical risk factors may be used to identify women at increased risk for recurrent spontaneous preterm birth.

Second trimester termination of pregnancy: a review by site and procedure type.

BACKGROUND: We hypothesized that complications for second trimester terminations are higher in a low-volume residency training program than in a high-volume private practice. STUDY DESIGN: Complications and cost were compared between three groups undergoing second trimester terminations: patients undergoing dilation and evacuation (D&E) at a university hospital (Hospital D&E, n=83) or medical pregnancy termination at a university hospital (Hospital Induction, n=89) and D&E at a private outpatient facility (Clinic D&E, n=253). RESULTS: Major complications occurred in 11% of the Hospital D&E, 10% of the Hospital Induction, and 1% of the Clinic D&E patients (p=.0019). Complication rates remained statistically significant when a logistic regression model was applied to the data. The mean total charge for the three respective groups was US$4625, US$5029 and US$1105 (p<.001). CONCLUSION: Second trimester terminations of pregnancy by D&E in well-selected patients in a dedicated outpatient facility can be safer and less expensive than hospital-based D&E or induction of labor.