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PubMed2001

Preterm delivery in patients admitted with preterm labor: a prediction study.

OBJECTIVE: To develop a model for prediction of preterm delivery in patients treated with parenteral tocolysis using combinations of maternal demographic and clinical factors. METHODS: We performed a retrospective cohort study using a perinatal database to identify women admitted with preterm labor and treated with parenteral tocolysis from 1980 to 1994. We developed an explanatory model using multiple logistic regression to determine the effect of four variables (prior preterm delivery, substance abuse, maternal complications and third-trimester care) on the likelihood of preterm delivery. For the prediction model, we initially included these four variables and then removed them in a stepwise fashion to determine the combination of the variables that offered the greatest model sensitivity and specificity. RESULTS: A total of 900 women were identified for the study and 247 (27%) had a preterm delivery. In the explanatory model, prior preterm delivery (OR 2.4; 95% CI 1.5-3.6), substance abuse (OR 2.2; 95% CI 1.2-5.1), initiation of care in the third trimester (OR 2.0; 95% CI 1.3-2.8) and medical complications of pregnancy (OR 1.8; 95% CI 1.2-2.6) increased the likelihood of preterm delivery. For the prediction tool, a three-variable model (prior preterm delivery, substance abuse and initiation of care in the third trimester) had high specificity (98%) and modest negative predictive value (73%). CONCLUSIONS: A simple three-variable model can correctly identify 98% of women with preterm labor treated with parenteral tocolysis who will not deliver preterm. Patients with no prior history of preterm delivery, no substance abuse and initiation of prenatal care before the third trimester have a 73% probability of not delivering preterm.

Adult↗

PubMed2001

Formula milk versus preterm human milk for feeding preterm or low birth weight infants.

BACKGROUND: Preterm human breast milk, compared with artificial formula milk, may provide insufficient nutrition for preterm or low birth weight infants. However, human milk may confer advantages in terms of a decreased incidence of gastrointestinal and neurodevelopmental adverse outcomes. OBJECTIVES: To determine if formula milk compared with preterm human milk leads to improved growth and development without significant adverse effects in preterm or low birth weight infants. SEARCH STRATEGY: The standard search strategy of the Cochrane Neonatal Review Group was used. This included electronic searches of the Cochrane Controlled Trials Register, MEDLINE, EMBASE and previous reviews including cross references. SELECTION CRITERIA: Randomised controlled trials comparing feeding with formula milk versus preterm human milk in preterm or low birth weight infants. DATA COLLECTION AND ANALYSIS: Data were extracted using the standard methods of the Cochrane Neonatal Review Group, with separate evaluation of trial quality and data extraction by each author and synthesis of data using relative risk and mean difference. MAIN RESULTS: Only one small trial fulfilled the pre-specified inclusion criteria (Gross 1983). In preterm and low birth weight infants, enteral feeding with protein-enriched standard calorie formula milk compared with unfortified donated preterm human milk resulted in a greater rate of short term weight gain, but not of increase in length or head circumference. In the group randomised to receive formula milk, there was an increase in the risk of feed intolerance of borderline statistical significance, but no evidence of an effect on necrotising enterocolitis. There are no data on long term growth parameters or on neurodevelopmental outcomes. There are no randomised comparisons of feeding with the preterm milk of the infant's mother versus formula milk. REVIEWER'S CONCLUSIONS: There are very limited data from randomised trials of feeding preterm or low birth weight infants with formula milk compared with preterm human milk. This may relate to a perceived difficulty of allocating an alternative enteral feed to an infant in cases where the infant's mother wishes to feed with expressed breast milk.

Enteral Nutrition↗

PubMed1996

The preterm prediction study: fetal fibronectin testing and spontaneous preterm birth. NICHD Maternal Fetal Medicine Units Network.

OBJECTIVE: To evaluate the presence of fetal fibronectin in the cervix and vagina as a screening test for spontaneous preterm birth. METHODS: Two thousand nine hundred twenty-nine women at ten centers were routinely screened every 2 weeks from 22-24 to 30 weeks for cervical and vaginal fetal fibronectin. A positive test was defined as a value equal to or greater than 50 ng/mL. The relation between a positive test at four gestational ages and spontaneous preterm birth at various intervals after the test was determined. RESULTS: In each testing period, 3-4% of the fetal fibronectin tests were positive. The correlation between cervical and vaginal fetal fibronectin at the same visit was always approximately 0.7 (P < .001), and that between cervical or vaginal fetal fibronectin in consecutive visits was between 0.17 and 0.25 (P < .001). The sensitivity of fetal fibronectin at 22-24 weeks to predict spontaneous preterm birth at less than 28 weeks was 0.63, and the relative risk for a positive versus negative test was 59. The specificity was always 96-98%, whereas the positive predictive value rose from 13% to 36% as the upper limit of the definition of preterm birth was increased from less than 28 to less than 37 weeks. The relative risk for spontaneous preterm birth after a positive fetal fibronectin test compared with a negative fetal fibronectin test varied substantially by testing period and by the definition of spontaneous preterm birth, but always remained greater than 4 and statistically significant. CONCLUSION: A positive cervical or vaginal fetal fibronectin test at 22-24 weeks predicted more than half of the spontaneous preterm births at less than 28 weeks (sensitivity 0.63). As the definition of spontaneous preterm birth was extended to include later gestational ages or when the fetal fibronectin test was performed later in pregnancy, the level of association between a positive fetal fibronectin test and spontaneous preterm birth, while remaining highly significant, tended to decrease. Although fetal fibronectin is an excellent test for predicting spontaneous preterm birth, we present no evidence that the use of this test will result in a reduction in spontaneous preterm birth.

Adult↗

PubMed2000

The preterm prediction study: granulocyte colony-stimulating factor and spontaneous preterm birth. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network.

OBJECTIVE: Granulocyte colony-stimulating factor is elevated in the amniotic fluid and plasma of women with chorioamnionitis and active preterm labor. We investigated the relationship between plasma granulocyte colony-stimulating factor and subsequent spontaneous preterm birth in pregnant women without symptoms. STUDY DESIGN: We performed a nested case-control study involving 194 women who had a singleton spontaneous preterm birth and 194 matched term control subjects from the patient pool (n = 2929) enrolled in the Preterm Prediction Study. Plasma collected at 24 and 28 weeks' gestation was analyzed for granulocyte colony-stimulating factor, and the results were compared with subsequent spontaneous preterm birth. RESULTS: Compared with term control subjects, women who were delivered of their infants spontaneously at <28 weeks' gestation had increased mean granulocyte colony-stimulating factor values at 24 weeks' gestation (84.7 +/- 38.4 vs 67.7 +/- 28.6 pg/mL; P =.049), and women who were delivered of their infants at <32 weeks' gestation had increased mean plasma granulocyte colony-stimulating factor values at 28 weeks' gestation (80.4 +/- 24.1 vs 55.9 +/- 16.5 pg/mL; P =. 001). At 24 weeks' gestation a granulocyte colony-stimulating factor value >75th percentile in control subjects (approximately 80 pg/mL) was found in 48.9% (23/47) of all women delivered of their infants at <32 weeks' gestation versus 14.9% (7/47) of the term control subjects (adjusted odds ratio, 6.2; 95% confidence interval, 1.8-20. 8). At 28 weeks' gestation a granulocyte colony-stimulating factor value >75th percentile was found in 36.8% (7/19) of women delivered of their infants at <32 weeks' gestation versus 5.3% (1/19) of term control subjects (adjusted odds ratio, 25.7; 95% confidence interval, 1.5-470.4). When measured at 24 or 28 weeks' gestation, granulocyte colony-stimulating factor did not predict spontaneous preterm birth at 32 to 34 weeks' gestation or at 35 to 36 weeks' gestation. CONCLUSION: In pregnant women without symptoms at 24 and 28 weeks' gestation, elevated plasma granulocyte colony-stimulating factor levels are associated with subsequent early (<32 weeks' gestation) spontaneous preterm birth, especially within the next 4 weeks, but not with late spontaneous preterm birth. These data provide further evidence that early spontaneous preterm birth is associated with an inflammatory process that is identifiable by the presence of a cytokine in maternal plasma several weeks before the early spontaneous preterm birth; however, later spontaneous preterm birth is not associated with this process.

Adolescent↗

PubMed1995

Risk of preterm delivery from preterm labor in high-risk patients.

This study aimed to determine the incidence of preterm labor and birth (< 37 weeks' gestation) in patients at high risk for early delivery. In this retrospective, descriptive study, 17,186 women with high-risk factors for early delivery were studied over a five-year period (1986-1990). Study groups included women with prior preterm delivery, multifetal gestations, uterine abnormalities and cervical factors. The rate of preterm labor for all patients averaged 40% (range, 30-46%). The rate of preterm delivery in the four groups ranged from 14% to 30% and averaged 19.7%. In those who experienced preterm delivery, only 32% of cases were due to preterm labor with advanced cervical dilatation, failed tocolysis or preterm premature rupture of membranes. The majority of early deliveries were due to medical or obstetric disorders as well as to patient/physician factors. The incidence of preterm labor remains significant when women have high-risk factors for preterm delivery. However, the incidence of preterm delivery, particularly that due to avoidable factors, such as failed tocolysis and preterm rupture of the membranes, is considerably lower than that quoted in the literature.

Adult↗

PubMedDate not supplied

Cervical inflammation and preterm delivery in pregnant women with a history of preterm delivery.

BACKGROUND: A previous preterm delivery is a risk factor for preterm delivery in a subsequent pregnancy. We tested the hypothesis that evidence of inflammation on a Papanicolaou smear obtained during pregnancy is a risk factor for preterm delivery for women with a history of preterm delivery. METHODS: We studied women who had two singleton deliveries at a university hospital during an 8-year period. Women eligible for our study were those whose first delivery was preterm (< 37 weeks of gestation) and for whom a Papanicolaou smear was obtained during the second pregnancy. These smears were examined for evidence of inflammation by a cytopathologist. Information about the second pregnancy was obtained by chart review. RESULTS: The cytopathologist reviewed Papanicolaou smears from 92 study pregnancies and found evidence of cervical inflammation on 34 smears (37 percent). Preterm delivery ended 24 (26.1 percent) of the second pregnancies. The incidence of preterm delivery in women with inflammation on Papanicolaou smear was 41.2 percent compared with an incidence of 17.2 percent in women without inflammation (relative risk of 2.40 with a 95 percent confidence interval of 1.19 to 4.83). This association remained significant after controlling for potential confounding variables. A stratified analysis found that the association of cervical inflammation with preterm delivery was limited to women who had systemic exposure to an antibiotic during pregnancy. CONCLUSION: Among pregnant women with a history of preterm delivery, evidence of inflammation on Papanicolaou smear was associated with an increased risk of preterm delivery. If replicated in other studies, this finding might have implications for the management of pregnancies in women with a history of preterm delivery.

Adult↗

PubMed2000

Kinesthetic stimulation for preventing apnea in preterm infants.

BACKGROUND: Recurrent apnea is common in preterm infants, particularly at very early gestational ages. These episodes of loss of effective breathing can lead to hypoxemia and bradycardia, which may be severe enough to require resuscitation including use of positive pressure ventilation or other treatments. Physical stimulation is often used to restart breathing and it is possible that repeated stimulation, such as with an oscillating mattress (kinesthetic stimulation), might prevent apnea and its consequences. OBJECTIVES: In preterm infants at risk for apnea, does prophylactic use of kinesthetic stimulation lead to a clinically important reduction in apnea and bradycardia, and use of intemittent positive preswsure ventilation (IPPV). SEARCH STRATEGY: The standard search strategy of the Neonatal Review Group was used. This included searches of the Oxford Database of Perinatal trials, Cochrane Controlled Trials Register, MEDLINE, previous reviews including cross references, abstracts, conferences and symposia proceedings, expert informants, journal handsearching mainly in the English language. SELECTION CRITERIA: All trials in preterm infants at risk of developing clinical apnea which utilised random or quasi-random allocation to treatment with an oscillating mattress or control, were eligible. DATA COLLECTION AND ANALYSIS: Standard methods of the Cochrane Collaboration and its Neonatal Review Group were used with separate evaluation of trial quality and data extraction by each author and synthesis of the data using relative risk. MAIN RESULTS: There were no differences in short term effects (apnea /bradycardia, IVH, use of IPPV, sleep/wake cycles and neurological status at discharge) or longterm effects (in one trial - growth and development to one year). REVIEWER'S CONCLUSIONS: Implications for practice. Prophylactic use of kinesthetic stimulation cannot be recommended to reduce apnea/bradycardia in preterm infants. Implications for research. There are currently no clear research questions regarding prophylactic use of kinesthetic stimulation to prevent apnea in preterm infants.

Apnea↗

PubMed2000

Continuous positive airway pressure versus theophylline for apnea in preterm infants.

BACKGROUND: Recurrent apnea is common in preterm infants, particularly at very early gestational ages. These episodes of loss of effective breathing can lead to hypoxemia and bradycardia which may be severe enough to require resuscitation including use of positive pressure ventilation. Theophylline stimulation of breathing and continuous positive airways pressure have been used to prevent apnea and its consequences. OBJECTIVES: The main objective was to determine in preterm infants with recurrent apnea, if treatment with CPAP compared with treatment with theophylline leads to a clinically important reduction in apnea or use of mechanical ventilation, without clinically important side effects. SEARCH STRATEGY: The standard search strategy of the Neonatal Review Group was used. This includes searches of the Oxford Database of Perinatal Trials, Cochrane Controlled Trials Register, MEDLINE, previous reviews including cross references, abstracts, conferences, symposia proceedings, expert informants and journal hand searching mainly in the English language. SELECTION CRITERIA: All trials using random or quasi-random allocation to CPAP or theophylline in preterm infants with clinical recurrent apnea/bradycardia were eligible. DATA COLLECTION AND ANALYSIS: Data were extracted using standard methods of the Cochrane Collaboration and its Neonatal Review Group, with separate evaluation of trial quality and data extraction by each author and synthesis of data using relative risk. MAIN RESULTS: The use of mask CPAP is associated with a higher treatment failure rate as measured by less than a 50% reduction in apnea or use of the alternative treatment [RR 2.89 (95% CI 1.12,7.47); RD 0.42 (95% CI 0. 11, 0.74)]. For every 2.4 infants (95% CI 1.4, 9.5) treated with mask CPAP rather than theophylline, there results one treatment failure. In the mask CPAP group there is more use of IPPV [RR 3.09 (1.42,6.70; RD 0.58 (95% CI 0.30, 0.86). For every 1.7 infants (95% CI 1.2, 3.3) treated with mask CPAP rather than theophylline, one infant is intubated for IPPV. In the mask CPAP group, there are trends towards more deaths in the first year, and in death or major disability in survivors at follow up, which do not reach significance. There are no differences in rates of necrotizing enterocolitis or major disability in survivors at follow up. REVIEWER'S CONCLUSIONS: Theophylline is more effective than mask CPAP for preterm infants with apnea. Since CPAP is no longer administered by mask, the results of this review have limited importance for current clinical practice. Further evaluation of the benefits and harms of CPAP vs theophylline for preterm infants with apnea requires further trials in which CPAP is administered by current methods.

Apnea↗

PubMed2000

Aerosolized diuretics for preterm infants with (or developing) chronic lung disease.

BACKGROUND: Lung disease in preterm infants is often complicated with lung edema. OBJECTIVES: The aim of this review is to assess the risks and benefits of aerosolized diuretic administration in preterm infants with or developing chronic lung disease (CLD). Primary objectives are to assess effects on short term outcome (changes in need for oxygen or ventilatory support) and effects on long-term outcome. Secondary objectives are to assess changes in pulmonary mechanics and potential complications of therapy. SEARCH STRATEGY: We used the standard search method of the Cochrane Neonatal Review Group. We used the following keywords: ¿ or ¿ and , limited to and limited to or . We searched Medline (1966-1998), Embase (1974-1998) and the Cochrane Controlled Trials Register (CCTR) from the Cochrane Library (1998, Issue 4). In addition, we hand searched several abstract books of national and international American and European Societies. SELECTION CRITERIA: We included in this analysis trials in which preterm infants with or developing chronic lung disease and at least five days of age were all randomly allocated to receive an aerosolized loop diuretic. Eligible studies needed to assess at least one of the outcome variables defined a priori for this systematic review. Primary outcome variables included important clinical outcomes, and secondary outcome variables included pulmonary mechanics and potential complications of therapy. DATA COLLECTION AND ANALYSIS: We used the standard method for the Cochrane Collaboration which is described in the Cochrane Collaboration Handbook. Two investigators extracted, assessed and coded separately all data for each study, using a form that was designed specifically for this review. Any disagreement was resolved by discussion. We combined parallel and cross-over trials and, whenever possible, transformed baseline and final outcome data measured on a continuous scale into change scores using Follmann's formula. MAIN RESULTS: We identified eight studies which met selection criteria. Most studies focused on pathophysiological parameters and did not assess effects on important clinical outcomes defined in this review or the potential complications of diuretic therapy. No study assessed the amount of diuretic effectively delivered to the patient. Furosemide was the only diuretic used in the eight studies included in this review. Among preterm infants < 3 weeks of age developing CLD, not enough information is available to assess the effect of aerosolized furosemide on outcome or lung function. Among infants > 3 weeks with CLD, a single aerosolized dose of 1 mg/kg of furosemide may transiently improve pulmonary mechanics. Not enough information is available to assess the effect of chronic administration of aerosolized furosemide on oxygenation and pulmonary mechanics. REVIEWER'S CONCLUSIONS: In preterm infants > 3 weeks with CLD administration of a single dose of aerosolized furosemide improves pulmonary mechanics. In view of the lack of data from randomized trials concerning effects on important clinical outcomes, routine or sustained use of aerosolized loop diuretics in infants with (or developing) CLD cannot be recommended based on current evidence. More double-blinded randomized trials are needed (1) to analyze factors likely to affect the response to aerosolized furosemide, e.g. , washout period and delivery of furosemide to distal airways, and (2) to assess the effects of chronic administration of aerosolized furosemide on mortality, O2 dependency, ventilator dependency, length of hospital stay and long-term outcome.

Aerosols↗

PubMed2006

Dynamic cervical change: is real-time sonographic cervical shortening predictive of preterm delivery in patients with symptoms of preterm labor?

OBJECTIVES: To determine prospectively if dynamic cervical change (spontaneous real-time cervical shortening) is predictive of preterm delivery at < 37 weeks' gestation in patients with symptoms of preterm labor. METHODS: This was a prospective study of patients at 23-34 weeks' gestation who were symptomatic for preterm labor. Patients underwent a 10-min real-time sonographic cervical length assessment with measurements taken at 1-min intervals. The presence or absence of dynamic cervical change, defined as real-time changes in cervical length observable to the naked eye of the sonologist during the examination, was recorded. Gestational age at delivery was obtained from medical records. Preterm delivery was defined as delivery at < 37 weeks' gestation. Dynamic cervical change and initial and minimum cervical lengths were assessed for prediction of preterm delivery. RESULTS: Seventy-six patients were enrolled, and 66 were available for outcome analysis. Thirty-one patients (47%) exhibited dynamic cervical change. Patients with dynamic change had shorter initial cervical lengths (27 mm vs. 36 mm, P = 0.001), shorter minimum cervical lengths (20 vs. 33 mm, P < 0.001) and larger changes in cervical length during the examination period (10 vs. 4 mm, P < 0.001). In the subgroup of patients with an initial cervical length > 30 mm, those with dynamic change delivered earlier than did those without dynamic change (36.8 vs. 38.6 weeks, P = 0.02), and a higher percentage delivered preterm (27% vs. 11%, odds ratio (OR), 3.0 (0.5-17.0)). Multivariate analysis showed that minimum cervical length was a better predictor of preterm delivery than was initial cervical length. CONCLUSIONS: Dynamic cervical change occurs frequently in association with shortened cervical length. In patients with longer initial cervical lengths, dynamic change may increase the risk for preterm delivery. When dynamic change is noted in a patient with preterm labor symptoms, use of the minimum cervical length observed may be better compared with initial cervical length for determining preterm delivery risk.

Adult↗

PubMed2005

Cervicovaginal fibronectin improves the prediction of preterm delivery based on sonographic cervical length in patients with preterm uterine contractions and intact membranes.

OBJECTIVE: The purpose of this study was to examine the diagnostic performance of ultrasonographic measurement of the cervical length and vaginal fetal fibronectin determination in the prediction of preterm delivery in patients with preterm uterine contractions and intact membranes. STUDY DESIGN: Ultrasound examination of the cervical length and fetal fibronectin determination in vaginal secretions were performed in 215 patients admitted with preterm uterine contractions (22-35 weeks) and cervical dilatation of </=3 cm. Outcome variables were the occurrence of preterm delivery within 48 hours, 7 days, and 14 days of admission, delivery </=32 and </=35 weeks, as well as the admission-to-delivery interval. Statistical analysis included chi-square test, receiver-operator characteristic (ROC) curve analysis, logistic regression, and survival analysis. RESULTS: The overall prevalence of preterm delivery </=35 weeks was 20% (43/215). The prevalence of spontaneous preterm delivery within 48 hours, 7 days, and 14 days of admission, and delivery </=32 and </=35 weeks were 7.9% (17/215), 13.0% (28/215), 15.8% (34/215), 8.9% (9/101), and 15.8% (34/215), respectively. ROC curve analysis and contingency tables showed a significant relationship between the occurrence of preterm delivery and both cervical length and fetal fibronectin results ( P < .01 for each). Both tests performed comparably in the prediction of spontaneous preterm delivery. However, when fetal fibronectin results were added to those of cervical length (<30 mm), a significant improvement in the prediction of preterm delivery was achieved. CONCLUSION: Fetal fibronectin adds prognostic information to that provided by sonographic measurement of the cervical length in patients with preterm uterine contractions and intact membranes.

Adult↗

PubMed2005

Increased intrauterine frequency of Ureaplasma urealyticum in women with preterm labor and preterm premature rupture of the membranes and subsequent cesarean delivery.

OBJECTIVE: The purpose of this study was to evaluate the prevalence of microbial invasion of the amniotic cavity at the time of preterm cesarean delivery for therapy-resistant preterm labor or preterm premature rupture of membranes, which are events that commonly are induced by infection, and to compare this group of patients with a group of patients who underwent preterm cesarean delivery for indications other than preterm labor or preterm premature rupture of membranes. STUDY DESIGN: We studied 207 consecutive women between 23 and 34 weeks of gestation who underwent cesarean delivery. These patients were divided into 3 groups according to the indication for cesarean delivery: patients with preterm labor (group 1), patients with preterm premature rupture of membranes (group 2), and patients with other indications (group 3). In the course of the surgical procedure, amniotic fluid, amniotic membrane, and placental tissue specimens were collected for the detection of pathogens. RESULTS: Ureaplasma urealyticum was detected in 43.9% (58/132) of the patients of groups 1 and 2, with no significant difference between these 2 subgroups. In group 3, which served as the comparison group, Ureaplasma urealyticum was isolated in only 2.7% (2/75) of the patients. Ureaplasma urealyticum as a single pathogen was more frequent than all obligate pathogens together (43.9% vs 39.3%). CONCLUSION: Our results provide evidence for an association between intrauterine colonization with Ureaplasma urealyticum and both therapy-resistant preterm labor and preterm premature rupture of membranes.

Adult↗

PubMed2005

The impact of interpregnancy interval and previous preterm birth on the subsequent risk of preterm birth.

OBJECTIVE: To examine the impact of the interpregnancy interval and a previous preterm birth on the subsequent risk of a preterm birth. METHODS: A retrospective analysis was conducted on a group of 4072 women who had at least two consecutive births, excluding multiple gestation, fetal anomalies, cervical incompetence, and stillbirth. Multivariate logistic regression was used to investigate the association between interpregnancy interval, preterm birth of the first child in the pair (index pregnancy), and the risk of a preterm birth of the second child in the pair (outcome pregnancy). RESULTS: Women with interpregnancy intervals of less than 12 months (odds ratio [OR] 1.3; 95% confidence interval [CI] 1.0-1.7) were at increased risks of preterm birth with the outcome pregnancy. Furthermore, there was an increased risk for a subsequent preterm birth in women who had a preterm birth in the index pregnancy (OR 4.2; 95% CI 3.0-6.0). The risk decreased as the interpregnancy interval increased, with a relatively low risk at 18 to 48 months; subsequently, it increased sharply. In contrast, women who had delivered their previous infants at term carried an increased risk of preterm birth with the outcome pregnancy only if the interval was less than 6 months. CONCLUSION: A difference was found in the impact of the interpregnancy interval on the subsequent risk of preterm birth between women with a prior preterm birth and those who previously delivered an infant at term.

Adult↗

PubMed2002

Preterm birth affects the intestinal response to parenteral and enteral nutrition in newborn pigs.

Maturation of gastrointestinal (GI) function in neonates is stimulated by enteral nutrition, whereas parenteral nutrition induces GI atrophy and malfunction. We investigated whether preterm birth alters the GI responses to parenteral and enteral nutrition. Pigs were delivered either preterm (107 d gestation) or at term (115 d gestation) and fed total parenteral nutrition (TPN) or enteral sow's milk (ENT) for 6 d after birth. Immaturity of the preterm pigs was documented by reduced blood pH, oxygen saturation and neutrophil granulocyte function, impaired intestinal immunoglobulin G uptake from colostrum, and altered relative weights of visceral organs (small intestine, liver, spleen, pancreas, and adrenals). For both ages at delivery, increases occurred in pancreatic weight (30-75%) and amylase activity (0.5- to 13-fold) after birth, but much more in ENT than in TPN pigs (P < 0.05). Six days of TPN feeding was associated with reduced intestinal weight for both delivery groups (60% of values in ENT, P < 0.001), but only in term TPN pigs was the weight lower than at birth (-20%, P < 0.05). Likewise, it was only in term TPN pigs that intestinal maltase activity increased, compared with ENT, and the absorption of glucose and proline decreased. Only in preterm pigs did TPN feeding increase lactase activity (+50% compared with ENT, P < 0.05). For both delivery ages, the mRNA of lactase-phloridzin hydrolase and sodium-coupled glucose transporter 1 were increased in TPN, compared with ENT. In conclusion, the trophic effect of enteral vs. parenteral nutrition on the GI tract is also present after preterm birth, but the postnatal maturation of many GI functions is modified, compared with term birth. The effects of nutritional regimen on the maturation of the gut epithelium in neonates depend on gestational age at birth.

Animals↗

PubMed2005

Whole body protein turnover and urea production of preterm small for gestational age infants fed fortified human milk or preterm formula.

OBJECTIVES: To investigate protein metabolism and urea production in preterm small for gestational age neonates fed a preterm formula or fortified human milk. METHODS: Ten preterm small for gestational age neonates were fed either their own mother's milk fortified with a powdered protein mineral supplement or a special preterm formula. Protein metabolism was determined using constant steady-state infusion of L-[ring-2H5]phenylalanine and L-[1-13C]valine. Urea production was determined from steady-state [13C]urea kinetics. RESULTS: Mean protein intake was 24% higher in the preterm formula group than in the fortified human milk group. No differences in protein turnover, synthesis and breakdown were observed between the two groups, but protein accretion was 71% to 79% higher in the preterm formula group than the fortified human milk group. Urea production rates were not different in the two groups. There was a strong negative correlation between urea production and protein accretion calculated from phenylalanine kinetics but not when calculated from valine kinetics. CONCLUSIONS: Preterm formula and fortified human milk appear equally well tolerated by preterm small for gestational age neonates, but protein accretion was higher in the preterm formula group. In preterm small for gestational age infants, both phenylalanine and valine kinetic methods can be used to accurately determine protein metabolism.

Carbon Isotopes↗

PubMedDate not supplied

Resolving the uncertainty of preterm symptoms: women's experiences with the onset of preterm labor.

OBJECTIVE: To describe expectant women's experiences with the onset of preterm labor. DESIGN: Qualitative, using grounded theory methods. SETTING: Southwestern tertiary women's hospital. PARTICIPANTS: Thirty pregnant women who were less than 35 weeks gestation, had experienced preterm labor within the past 7 days, and had no previous experience with preterm labor. DATA SOURCE: Taped and transcribed interviews. RESULTS: Themes that emerged from the interview data included the following: recognition and naming of sensations, a consistent pattern of attribution of symptoms, the threat or risk inferred by the attributed cause of the symptom pattern, the associated certainty or uncertainty about these attributions, the process of interpreting and verifying symptom meaning, and the decision to self-manage the symptoms or engage health care assistance. The core process of women experiencing the onset of preterm labor symptoms was identified as "resolving the uncertainty of preterm labor symptoms: recognizing and responding to the possibilities." CONCLUSIONS: Preterm labor often is not within expectant women's consciousness. They may attribute the symptoms to nonthreatening causes, which results in delays in seeking care for preterm labor. Education about symptom patterns at the onset of preterm labor will increase the probability that women and their health care providers will recognize and interpret the early, subtle symptoms that herald the onset of preterm labor. Uncertainty in illness theory and attribution theory offer frameworks for understanding women's experiences with the onset of preterm labor.

Adult↗

PubMed1998

The preterm prediction study: the value of new vs standard risk factors in predicting early and all spontaneous preterm births. NICHD MFMU Network.

OBJECTIVES: This study was undertaken to determine the relationship between fetal fibronectin, short cervix, bacterial vaginosis, other traditional risk factors, and spontaneous preterm birth. METHODS: From 1992 through 1994, 2929 women were screened at the gestational age 22 to 24 weeks. RESULTS: The odds ratios for spontaneous preterm birth were highest for fetal fibronectin, followed by a short cervix and history of preterm birth. These factors, as well as bacterial vaginosis, were more strongly associated with early than with late spontaneous preterm birth. Bacterial vaginosis was more common--and a stronger predictor of spontaneous preterm birth--in Black women, while body mass index less than 19.8 was a stronger predictor in non-Black women. This analysis suggests a pathway leading from Black race through bacterial vaginosis and fetal fibronectin to spontaneous preterm birth. Prior preterm birth is associated with spontaneous preterm birth through a short cervix. CONCLUSIONS: Fetal fibronectin and a short cervix are stronger predictors of spontaneous preterm birth than traditional risk factors. Bacterial vaginosis was found more often in Black than in non-Black women and accounted for 40% of the attributable risk for spontaneous preterm birth at less than 32 weeks.

Cervix Uteri↗

PubMed1994

Can fetal biophysical observations anticipate outcome in preterm labor or preterm rupture of membranes?

OBJECTIVE: To evaluate fetal biophysical testing as a predictor of preterm delivery after preterm labor or preterm rupture of the membranes (PROM). METHODS: We studied 50 women with suspected preterm labor and intact membranes and 25 women with PROM but not in labor between 28 and 36 weeks' gestation. Before treatment, each subject had cervical Bishop scoring and 1-hour ultrasound observation of fetal heart rate, breathing, body movements, and flexion-extensions. Data were compared with t tests, chi 2 tests, or receiver operating curves. RESULTS: The mean gestational age at entry was similar in both groups. Twenty (80%) PROM and ten (18%) preterm labor patients delivered within 72 hours of admission; two (8%) PROM and 38 (76%) preterm labor patients delivered more than 7 days after admission. Absent breathing and body movements had high positive predictive values (100%) but moderate sensitivities (less than 55%) for predicting delivery within 72 hours or 7 days in the PROM and preterm labor groups. These sensitivities increased to nearly 70% with the addition of Bishop scores. The optimal diagnostic cutoffs for delivery within 72 hours or 7 days were a breathing incidence below 1% for the PROM group and a body movement incidence below 1% for the preterm labor group, and a breathing incidence of at most 5%. CONCLUSIONS: Complete absence of one biophysical variable confers limited sensitivity but high positive predictive value for early delivery in patients with preterm labor or PROM. The use of cutoff percentages for the incidence of individual variables improved sensitivity for both conditions. Cervical scoring added to biophysical monitoring by improving the sensitivity for early delivery of patients in preterm labor.

Chi-Square Distribution↗