The contemporary value of dedicated preterm birth clinics for high-risk singleton pregnancies: 15-year outcomes from a leading maternal centre

Validating the ratio of insulin like growth factor binding protein 4 to sex hormone binding globulin as a prognostic predictor of preterm birth in Viet Nam: a case-cohort study

OBJECTIVE

To validate a serum biomarker developed in the USA for preterm birth (PTB) risk stratification in Viet Nam.

METHODS

Women with singleton pregnancies (n = 5000) were recruited between 19+0-23+6 weeks' gestation at Tu Du Hospital, Ho Chi Minh City. Maternal serum was collected from 19+0-22+6 weeks' gestation and participants followed to neonatal discharge. Relative insulin-like growth factor binding protein 4 (IGFBP4) and sex hormone binding globulin (SHBG) abundances were measured by mass spectrometry and their ratio compared between PTB cases and term controls. Discrimination (area under the receiver operating characteristic curve, AUC) and calibration for PTB <37 and <34 weeks' gestation were tested, with model tuning using clinical factors. Measured outcomes included all PTBs (any birth ≤37 weeks' gestation) and spontaneous PTBs (birth ≤37 weeks' gestation with clinical signs of initiation of parturition).

RESULTS

Complete data were available for 4984 (99.7%) individuals. The cohort PTB rate was 6.7% (n = 335). We observed an inverse association between the IGFBP4/SHBG ratio and gestational age at birth (p = 0.017; AUC 0.60 [95% CI, 0.53-0.68]). Including previous PTB (for multiparous women) or prior miscarriage (for primiparous women) improved performance (AUC 0.65 and 0.70, respectively, for PTB <37 and <34 weeks' gestation). Optimal performance (AUC 0.74) was seen within 19-20 weeks' gestation, for BMI >21 kg/m2 and age 20-35 years.

CONCLUSION

We have validated a novel serum biomarker for PTB risk stratification in a very different setting to the original study. Further research is required to determine appropriate ratio thresholds based on the prevalence of risk factors and the availability of resources and preventative therapies.

Screening for women at risk of spontaneous preterm birth, including cervical incompetence

Preterm births remain one of the biggest challenges in obstetrics worldwide. With the advancement of neonatal care, more premature neonates survive with long term consequences. Therefore, preventing or delaying preterm births starting from the preconceptional or antenatal periods are important. Among the numerous screening strategies described, not one can fit into all. Nonetheless, approaches including identifying women with modifiable risk factors for preterm births, genitourinary infections and short cervical length are the most useful. In this article, the current evidence is summarized and the best strategies for common clinical scenerios including cervical incompetence, history of second trimester loss or early preterm births, incidental short cervix and multiple pregnancy are discussed.

Identification of biochemical biomarkers associated with premature cervical shortening in high-risk, asymptomatic pregnant women: a retrospective data analysis

Reliably predicting spontaneous preterm birth remains challenging, therefore it persists as a major contributor to perinatal morbidity and mortality. The use of biomarkers to predict premature cervical shortening, a recognised risk factor for spontaneous preterm birth, is yet to be fully explored in current literature. This study evaluates seven cervicovaginal biochemical biomarkers as possible predictors of premature cervical shortening. Asymptomatic, high-risk women (n = 131) presenting to a specialised preterm birth prevention clinic were analysed through a retrospective data analysis. Cervicovaginal biochemical biomarker concentrations were obtained, and the shortest cervical length measurement, up to 28 weeks' gestation, was recorded. Associations between biomarker concentration and cervical length were then analysed. Of the seven biochemical biomarkers, Interleukin-1 Receptor Antagonist and Extracellular Matrix Protein-1 had statistically significant relationships with cervical shortening below 25 mm. Further investigation is required to validate these findings and any downstream clinical utility, with intentions to improve perinatal outcomes.IMPACT STATEMENTWhat is already known on this subject? Preterm birth is a major cause of perinatal morbidity and mortality. A woman's risk of delivering preterm is currently stratified using historical risk factors, mid-gestation cervical length, and biochemical biomarkers such as foetal fibronectin.What do the results of this study add? In a cohort of high-risk, asymptomatic pregnant women, two cervicovaginal biochemical biomarkers, Interleukin-1 Receptor Antagonist and Extracellular Matrix Protein-1, displayed associations with premature cervical shortening.What are the implications of these findings for clinical practice and/or further research? Further investigation into the possible clinical utility of these biochemical biomarkers is warranted, with a view to improving preterm birth prediction and antenatal resource utilisation, thereby reducing the burden of preterm birth and its sequelae in a cost-effective manner.

Diagnostic value of Serum Amyloid A, Interleukin-6 in gravidas with spontaneous preterm birth

PURPOSE

Spontaneous preterm birth (SPB) can't be predicted accurately nowadays. We aim to investigate the value of serum amyloid A(SAA) and interleukin-6(IL-6) for forecasting the risk of SPB.

METHODS

A total of 302 pregnant women who completed delivery in our hospital from January 2019 to December 2021 were included. According to gestational days, they were divided into the case group (28-33⁺⁶ weeks, 41 cases; 34-36⁺⁶ weeks, 96 cases) and the control group (37-42 weeks, 165 cases). The general data of the two groups were analyzed and the values of SAA and IL-6 in speculating the risk of SPB were studied in this study.

RESULTS

The levels of SAA and IL-6 in the case group were higher than those in the control group(P < 0.05), and the most practical value of SAA and IL-6 access SPB risk were 17.35 mg/L, 112.41 pg/mL respectively. The area under the ROC curve of diagnosis to predict SPB were 0.8849, 0.8664.

CONCLUSIONS

The assessment of SPB risk by SAA and IL-6 bearscertain clinical value, which could assist clinicians in recognizing and evaluating the potential dangers of SPB.

Abnormal vaginal flora and spontaneous preterm birth in high-risk singleton pregnancies with cervical cerclage

OBJECTIVE

To investigate abnormal vaginal and suture-based bacterial flora for associations with spontaneous preterm birth in high-risk singleton pregnancies with an ultrasound-indicated or emergency cervical cerclage.

MATERIALS AND METHODS

A retrospective study of 196 singleton pregnancies with an ultrasound-indicated or emergency cerclage at the Royal Women's Hospital, Australia, from 2004 to 2018. High vaginal swabs were collected regularly between 14 and 26 weeks' gestation, including pre- and post-cerclage insertion, and sent for microscopy and culture. Cervical suture was cultured upon removal. Primary outcomes were spontaneous preterm birth <37, <34 and <30 weeks.

RESULTS

43.4% (85/196) of women delivered preterm. The acquisition and persistence of vaginal Escherichia coli following cerclage insertion were independently associated with spontaneous preterm birth <37 weeks (p = .0225, p = .0477). Escherichia coli growth from the cervical suture upon removal was associated with spontaneous preterm birth <34 weeks (p = .0458). The acquisition of vaginal mixed anaerobes post-cerclage was independently associated with spontaneous preterm birth <34 weeks (p = .0480).

CONCLUSION

For singleton pregnancies with an ultrasound-indicated or emergency cerclage, the presence of vaginal or suture-based Escherichia coli following cerclage insertion yields increased risk of cerclage failure and spontaneous preterm birth.

Psychological well-being of women at high risk of spontaneous preterm birth cared for in a specialised preterm birth clinic: a prospective longitudinal cohort study

OBJECTIVES

To assess the psychological well-being of pregnant women at increased risk of spontaneous preterm birth, and the impact of care from a preterm birth clinic.

DESIGN

Single-centre longitudinal cohort study over 1 year, 2018-2019.

SETTING

Tertiary maternity hospital in Auckland, New Zealand.

PARTICIPANTS

Pregnant women at increased risk of spontaneous preterm birth receiving care in a preterm birth clinic.

INTERVENTION

Participants completed three sets of questionnaires (State-Trait Anxiety Inventory, Edinburgh Postnatal Depression Scale, and 36-Item Short Form Survey)-prior to their first, after their second, and after their last clinic appointments. Study-specific questionnaires explored pregnancy-related anxiety and perceptions of care.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was the mean State-Anxiety score. Secondary outcomes included depression and quality of life measures.

RESULTS

73/97 (75.3%) eligible women participated; 41.1% had a previous preterm birth, 31.5% a second trimester loss and 28.8% cervical surgery; 20.6% had a prior mental health condition. 63/73 (86.3%) women completed all questionnaires. The adjusted mean state-anxiety score was 39.0 at baseline, which decreased to 36.5 after the second visit (difference -2.5, 95% CI -5.5 to 0.5, p=0.1) and to 32.6 after the last visit (difference -3.9 from second visit, 95% CI -6.4 to -1.5, p=0.002). Rates of anxiety (state-anxiety score >40) and depression (Edinburgh Postnatal Depression Scale score >12) were 38.4%, 34.8%, 19.0% and 13.7%, 8.7%, 9.5% respectively, at the same time periods. Perceptions of care were favourable; 88.9% stated the preterm birth clinic made them significantly or somewhat less anxious and 87.3% wanted to be seen again in a future pregnancy.

CONCLUSIONS

Women at increased risk of spontaneous preterm birth have high levels of anxiety. Psychological well-being improved during the second trimester; women perceived that preterm birth clinic care reduced pregnancy-related anxiety. These findings support the ongoing use and development of preterm birth clinics.