Diagnosis of early preterm labour

Outcomes of pregnancy after bariatric surgery: results of a French matched-cohort study

BACKGROUND

While the benefits of bariatric surgery (BS) on pregnancy outcomes have been demonstrated for women compared with matched controls on presurgery body mass index (pB-BMI), data are lacking and those benefits are uncertain compared with matched controls on prepregnancy BMI (pP-BMI).

OBJECTIVES

Our study aimed to evaluate outcomes (obstetrical and neonatal) of single pregnancy in women previously exposed to BS compared with women unexposed to BS matched on pB-BMI and pP-BMI.

SETTINGS

Retrospective matched cohort study from 2 observational studies of pregnant women conducted in a French administrative county (Finistère).

METHODS

From April 1, 2015 to January 31, 2019, pregnant women with previous BS (n = 52) were included and compared with 2 different control groups as follows: group A (n = 104), matched for pB-BMI, age, and parity; and group B (n = 104), matched for pP-BMI, age, and parity.

RESULTS

In women exposed to BS, mean age was 27.1 (±4.9) years and pB-BMI was 46.0 (±4.6) kg/m². Operated women differed significantly from group A but not from group B for pP-BMI (29.4 ± 6.1 versus 45.3 ± 4.5 group A versus 28.6 ± 6.6 group B) and gestational diabetes (12.0% versus 44.0% group A versus 17.0% group B), respectively. In the group of women exposed to BS, birth weight (g) was significantly lower (2960 ± 545 versus 3381 ± 735 group A versus 3310 ± 645 group B) and large-for-gestational-age infants less frequent (0% versus 13% group A versus 8% group B).

CONCLUSION

Bariatric surgery reduced risks of excessive fetal growth and gestational diabetes with a trend for a higher risk of small-for-gestational-age, despite matching on pP-BMI suggesting a risk associated to BS and solely to previous surgery-induced weight loss.

Combined insulin-like growth factor binding protein-1/interleukin-6 (Premaquick) versus fetal fibronectin for predicting preterm delivery among women with preterm contractions

OBJECTIVES

To compare accuracy between Premaquick (combined test for native insulin-like growth factor binding protein-1 (IGFBP-1), total IGFBP-1, and interleukin-6) and fetal fibronectin (Ffn) in predicting preterm delivery.

METHODS

Prospective study among women at 28-36⁺⁶ gestational weeks with threatened preterm labor attending Federal Medical Center, Owerri, Nigeria, from August 2017 to February 2019. Cervico-vaginal fluids were collected and tested by Premaquick and Ffn tests. The women were followed for 14 days. Sensitivity, specificity, and negative (NPV) and positive (PPV) predictive value for delivery were compared between the tests.

RESULTS

Among 213 women assessed for eligibility, 183 were enrolled and 175 completed the study. The sensitivity, specificity, PPV, NPV, and accuracy of the Premaquick versus Ffn tests were, respectively, 96.3% versus 51.9%, 97.6% versus 98.4%, 89.7% versus 87.5%, 99.2% versus 90.3% and 97.3% versus 90.0% for preterm delivery within 14 days. Ffn had higher specificity (98.5% vs 97.8%; P>0.99), but Premaquick had higher PPV (92.7% vs 90.9%; P>0.99).

CONCLUSION

Both tests seem to have high utility in predicting preterm delivery, but Premaquick showed higher accuracy in terms of sensitivity and PPV. Premaquick might be a feasible alternative to Ffn for predicting preterm delivery among symptomatic women in a low-income setting.

[Preterm Birth Screening: What Does Really Make Sense?]

Preterm Birth Screening: What Does Really Make Sense? Abstract. Spontaneous preterm birth is a syndrome triggered by multiple mechanisms. In view of the pathophysiological heterogeneity of preterm birth, a single biomarker cannot show the required high negative and positive predictive values. From a clinical point of view, anamnesis, sonographic measurement of cervical length, and placental alpha-microglobulin-1 (PAMG-1) testing from cervico-vaginal secretion are established. Further prospective, large-scale longitudinal studies must validate the combined use of new biomarkers.

The fetal fibronectin test: 25 years after its development, what is the evidence regarding its clinical utility? A systematic review and meta-analysis

Background: The identification of women at risk for preterm birth should allow interventions which could improve neonatal outcome. Fetal fibronectin, a glycoprotein which acts normally as glue between decidua and amniotic membranes could be a good marker of impending labour when its concentration in cervicovaginal secretions between 22 and 36 weeks of gestation is ≥50 ng/mL. Many authors worldwide have tested this marker with many different methodologies and clinical settings, but conclusions about its clinical use are mixed. It is time for a comprehensive update through a systematic review and meta-analysis.Methods: We searched PubMed, Cochrane Library, and Embase, supplemented by manual search of bibliographies of known primary and review articles, international conference papers, and contact with experts from 1-1990 to 2-2018. We have selected all type of studies involving fetal fibronectin test accuracy for preterm delivery. Two authors independently extracted data about study characteristics and quality from identified publications. Contingency tables were constructed. Reference standards were preterm delivery before 37, 36, 35, 34, and 32 weeks, within 28, 21, 14, or 7 d and within 48 h. Data were pooled to produce summary likelihood ratios for positive and negative tests results.Results: One hundred and ninety-three primary studies were identified allowing analysis of 53 subgroups. In all settings, none of the summary likelihood ratios were >10 or <0.1, thus indicating moderate prediction, particularly in asymptomatic women and in multiple gestations.Conclusions: The fetal fibronectin test should not be used as a screening test for asymptomatic women. For high-risk asymptomatic women, and especially for women with multiple pregnancies, the performance of the fetal fibronectin test was also too low to be clinically relevant. Consensual use as a diagnostic tool for women with suspected preterm labor, the best use policy probably still depends on local contingencies, future cost-effectiveness analysis, and comparison with other more recent available biochemical markers.

Prediction of spontaneous preterm delivery in singleton pregnancies: where are we and where are we going? A review of literature

Prematurity is the chief cause of neonatal morbidity and mortality. The objective of this study is to review the different methods for predicting preterm delivery in asymptomatic pregnant women and in situations of threatened preterm delivery. A search of the PubMed/Medline database was carried out for the years 1980-2012. We included studies for predicting preterm birth in asymptomatic and symptomatic patients. Models for predicting preterm delivery based on maternal factors, cervical length and obstetric history in first trimester of pregnancy is a valuable avenue of research. Nevertheless, prediction accuracy still needs to be improved. In the second and third trimesters, routine digital vaginal examination is of no value in asymptomatic women. Echography of the cervix is not useful except in patients with a history of late miscarriage or preterm delivery in order to offer them a preventive treatment. In symptomatic women, the combination of digital vaginal examination, cervical echography and fibronectin gives the best predictive results. Electromyography of the uterus and elastography of the cervix are interesting avenues for future research. Identifying patients at risk of preterm delivery should be considered differently at each stage of pregnancy.

The diagnosis and natural history of false preterm labor

OBJECTIVE

To estimate the natural history of pregnancies in women who present with preterm labor symptoms and who are sent home with a diagnosis of false labor.

METHODS

A prospective observational study of women with singletons and intact membranes who presented to triage between 24 0/7 and 33 6/7 weeks of gestation with preterm labor symptoms and cervical dilation less than 2 cm was conducted. Women sent home with a diagnosis of false preterm labor were analyzed against a comparable general obstetric population delivered during the same time period. The primary outcome was delivery before 37 weeks of gestation. Secondary outcomes included the interval between presentation and delivery, as well as maternal and neonatal outcomes.

RESULTS

Of the 843 women who met inclusion criteria, 690 (82%) were sent home with a diagnosis of false preterm labor and 153 (18%) were admitted to labor and delivery. When analyzed compared with a comparable general obstetric population, women sent home had a similar rate of birth before 34 weeks of gestation (2% compared with 1%, P=.28) but a higher rate of birth between 34 and 36 weeks of gestation (5% compared with 2%, P<.001). There was no difference in neonatal mortality (0% compared with 0.3%, P=.18). Women with cervical dilation of 1 cm at discharge were more likely to deliver before 34 weeks of gestation compared with nondilated women (5% compared with 1%, P=.02); however, 89% of the 1-cm group delivered more than 21 days after presentation.

CONCLUSION

Women sent home with a diagnosis of false preterm labor are not at increased risk for early preterm birth or neonatal mortality; however, they are at increased risk for late preterm birth.

LEVEL OF EVIDENCE

II.

Transvaginal sonographic evaluation of the cervix in asymptomatic singleton pregnancy and management options in short cervix

Preterm delivery (PTD), defined as birth before 37 completed weeks of gestation, is the leading cause of perinatal morbidity and mortality. Evaluation of the cervical morphology and biometry with transvaginal ultrasonography at 16–24 weeks of gestation is a useful tool to predict the risk of preterm birth in low- and high-risk singleton pregnancies. For instance, a sonographic cervical length (CL) > 30 mm and present cervical gland area have a 96-97% negative predictive value for preterm delivery at <37 weeks. Available evidence supports the use of progesterone to women with cervical length ≤25 mm, irrespective of other risk factors. In women with prior spontaneous PTD with asymptomatic cervical shortening (CL ≤ 25 mm), prophylactic cerclage procedure must be performed and weekly to every two weeks follow-up is essential. This article reviews the evidence in support of the clinical introduction of transvaginal sonography for both the prediction and management of spontaneous preterm labour.

Digital examination and transvaginal scan - competing or complementary for predicting preterm birth?

BACKGROUND

The transvaginal ultrasonographic cervix scan has partly replaced digital examination for diagnosing preterm birth; conflicting results are reported about their respective contribution to birth prediction.

OBJECTIVE

To review the predictive value of digital examination and transvaginal scan in low-risk asymptomatic and symptomatic women before treatment.

METHODS

A literature search of PubMed, Web of Science and Cochrane Databases from 1994 to 2010 and selected reference lists was carried out. Randomized controlled trials, retrospective and prospective cohort studies, outcome research and studies of clinical decision rules were included.

RESULTS

The studies showed that methods for the estimation of cervical ripening are not unequivocal nor is the nomenclature for digital examination. Evidence for routine screening for premature cervical ripening in asymptomatic low-risk women is insufficient. Knowledge of ultrasonographic cervical length in symptomatic women was not associated with a significantly improved outcome in symptomatic women, but may help to reduce length of hospitalization. In women selected by the Bishop Score, a transvaginal scan may reduce the number of false-positive results.

CONCLUSIONS

Clarification on the methods for performing cervical assessment is needed. The evidence that transvaginal scanning of the cervix improves outcome in symptomatic women is insufficient. The methods for assessing cervical change should be regarded as complementary.

All Our Babies Cohort Study: recruitment of a cohort to predict women at risk of preterm birth through the examination of gene expression profiles and the environment

Background

Preterm birth is the leading cause of perinatal morbidity and mortality. Risk factors for preterm birth include a personal or familial history of preterm delivery, ethnicity and low socioeconomic status yet the ability to predict preterm delivery before the onset of preterm labour evades clinical practice. Evidence suggests that genetics may play a role in the multi-factorial pathophysiology of preterm birth. The All Our Babies Study is an on-going community based longitudinal cohort study that was designed to establish a cohort of women to investigate how a women's genetics and environment contribute to the pathophysiology of preterm birth. Specifically this study will examine the predictive potential of maternal leukocytes for predicting preterm birth in non-labouring women through the examination of gene expression profiles and gene-environment interactions.

Methods/Design

Collaborations have been established between clinical lab services, the provincial health service provider and researchers to create an interdisciplinary study design for the All Our Babies Study. A birth cohort of 2000 women has been established to address this research question. Women provide informed consent for blood sample collection, linkage to medical records and complete questionnaires related to prenatal health, service utilization, social support, emotional and physical health, demographics, and breast and infant feeding. Maternal blood samples are collected in PAXgene™ RNA tubes between 18-22 and 28-32 weeks gestation for transcriptomic analyses.

Discussion

The All Our Babies Study is an example of how investment in clinical-academic-community partnerships can improve research efficiency and accelerate the recruitment and data collection phases of a study. Establishing these partnerships during the study design phase and maintaining these relationships through the duration of the study provides the unique opportunity to investigate the multi-causal factors of preterm birth. The overall All Our Babies Study results can potentially lead to healthier pregnancies, mothers, infants and children.

Role of phIGFBP-1 and ultrasound cervical length in predicting pre-term labour

This prospective observational study was to evaluate the efficacy of combining phosphorylated insulin-like growth factor binding protein-1 (phIGFBP-1) and transvaginal ultrasound cervical length (CL) compared with either indicator alone in predicting pre-term labour (PTL). Women with singleton pregnancy between 24 and 36 weeks' gestation with evidence of PTL were subjected to phIGFBP-1 and CL tests. Of the 51 women, five were tested positive (phIGFBP-1 positive and CL <2.5 cm) for combination of phIGFBP-1 and CL (four delivered within 1 week), whereas 46 tested negative, of which, only one delivered. A much higher negative predictivity (NP), positive predictivity (PP) and specificity (SP) in the combination test was seen compared with phIGFBP-1 or CL alone (NP: 97.8% vs 97.7% vs 97.1%; PP: 80.0% vs 51.1% and CL 23.5%; SP: 97.8% vs 93.5% vs 71.1%, respectively). The cervical os dilatation of 2 cm with combined positive test (p = 0.001) indicated a higher likelihood of PTL.

Effect of maternal clinical chorioamnionitis on neonatal morbidity in very-low birthweight infants: a case-control study

AIMS

To assess the relationship between maternal clinical chorioamnionitis and neonatal outcome in preterm very-low birthweight (VLBW) infants.

METHODS

An observational case-control study was conducted in the Neonatology Services of 12 acute-care teaching hospitals in Spain. Between January 2004 and December 2006, all consecutive VLBW (< or =1500 g) infants born to a mother with clinical chorioamnionitis were enrolled. Controls were infants without chorioamnionitis matched by gestational age who were born immediately after each index case.

RESULTS

There were 165 cases and 163 controls. A significantly higher percentage of cases than controls required intubation (53% vs. 35.8%), had normal intrauterine growth (98.1% vs. 84.7%), were born in a tertiary center (inborn) (95.1% vs. 89.1%), from single gestations (76.4% vs. 65.6%) and vaginal delivery (47.3% vs. 33.3%), showed a lower Apgar score at 5 min, and presented a higher rate of early-onset sepsis (10.4% vs. 1.2%). Older maternal age (32.5 vs. 30.8 years), premature labor (67.3% vs. 25.8%), premature rupture of membranes (61.3% vs. 25.8%), and antibiotic treatment (88.5% vs. 52.3%) were significantly more frequent among cases than controls.

CONCLUSIONS

After controlling by gestational age, maternal chorioamnionitis was associated with neonatal depression and early sepsis but not with other prematurity-related complications.