Economic consequences of over-diagnosis of threatened preterm labor

Randomized trial of screening for preterm birth in low-risk women - the preterm birth screening study

BACKGROUND

Preterm birth is a major cause of perinatal morbidity and mortality. It is unclear whether the introduction of a universal transvaginal ultrasound cervical length screening program in women at low risk for preterm delivery is associated with a reduction in the frequency of preterm birth.

OBJECTIVE

To test the hypothesis that the introduction of a midtrimester universal transvaginal ultrasound cervical length screening program in asymptomatic singleton pregnancies without prior preterm delivery would reduce the rate of preterm birth at <37 weeks of gestation.

STUDY DESIGN

This study was a multicenter nonblinded randomized trial of screening of asymptomatic singleton pregnancies without prior spontaneous preterm birth, who were randomized to either cervical length screening program (ie, intervention group) or no screening (ie, control group). Participants were randomized at the time of their routine anatomy scan between 18 0/7 and 23 6/7 weeks of gestation. Women randomized in the screening group received cervical length measurement. Those who were found to have cervical length ≤25 mm were offered 200 mg vaginal progesterone daily along with cervical pessary. The primary outcome was preterm birth at <37 weeks. The risk of primary outcome was quantified by the relative risk with 95% confidence interval, and was based on the intention-to-screen principle.

RESULTS

A total of 1334 asymptomatic women with singleton pregnancies and without prior preterm birth, were included in the trial. Out of the 675 women randomized in the transvaginal ultrasound cervical length screening group, 13 (1.9%) were found to have transvaginal ultrasound cervical length ≤25 mm during the screening. Preterm birth at <37 weeks of gestation occurred in 48 women in the transvaginal ultrasound cervical length screening group (7.5%), and 54 women in the control group (8.7%) (relative risk, 0.86; 95% confidence interval, 0.59-1.25). Women randomized in the transvaginal ultrasound cervical length screening group had no significant differences in the incidence of preterm birth at less than 34, 32, 30, 28, and 24 weeks of gestation.

CONCLUSION

The introduction of a universal transvaginal ultrasound cervical length screening program at 18 0/6 to 23 6/7 weeks of gestation in singleton pregnancies without prior spontaneous preterm birth, with treatment for those with cervical length ≤25 mm, did not result in significant lower incidence of preterm delivery than the incidence without the screening program.

Development and validation of a transcriptomic signature-based model as the predictive, preventive, and personalized medical strategy for preterm birth within 7 days in threatened preterm labor women

Preterm birth (PTB) is the leading cause of neonatal death. The essential strategy to prevent PTB is the accurate identification of threatened preterm labor (TPTL) women who will have PTB in a short time (< 7 days). Here, we aim to propose a clinical model to contribute to the effective prediction, precise prevention, and personalized medical treatment for PTB < 7 days in TPTL women through bioinformatics analysis and prospective cohort studies. In this study, the 1090 key genes involved in PTB < 7 days in the peripheral blood of TPTL women were ascertained using WGCNA. Based on this, the biological basis of immune-inflammatory activation (e.g., IFNγ and TNFα signaling) as well as immune cell disorders (e.g., monocytes and Th17 cells) in PTB < 7 days were revealed. Then, four core genes (JOSD1, IDNK, ZMYM3, and IL1B) that best represent their transcriptomic characteristics were screened by SVM and LASSO algorithm. Therefore, a prediction model with an AUC of 0.907 was constructed, which was validated in a larger population (AUC = 0.783). Moreover, the predictive value (AUC = 0.957) and clinical feasibility of this model were verified through the clinical prospective cohort we established. In conclusion, in the context of Predictive, Preventive, and Personalized Medicine (3PM), we have developed and validated a model to predict PTB < 7 days in TPTL women. This is promising to greatly improve the accuracy of clinical prediction, which would facilitate the personalized management of TPTL women to precisely prevent PTB < 7 days and improve maternal-fetal outcomes.

Detection of spontaneous preterm birth by maternal urinary volatile organic compound analysis: A prospective cohort study

Accurate prediction of preterm birth is currently challenging, resulting in unnecessary maternal hospital admittance and fetal overexposure to antenatal corticosteroids. Novel biomarkers like volatile organic compounds (VOCs) hold potential for predictive, bed-side clinical applicability. In a proof of principle study, we aimed to assess the predictive potential of urinary volatile organic compounds in the identification of pregnant women at risk for preterm birth. Urine samples of women with a high risk for preterm birth (≧24 + 0 until 36 + 6 weeks) were collected prospectively and analyzed for VOCs using gas chromatography coupled with an ion mobility spectrometer (GS-IMS). Urinary VOCs of women delivering preterm were compared with urine samples of women with suspicion of preterm birth collected at the same gestation period but delivering at term. Additionally, the results were also interpreted in combination with patient characteristics, such as physical examination at admission, microbial cultures, and placental pathology. In our cohort, we found that urinary VOCs of women admitted for imminent preterm birth were not significantly different in the overall group of women delivering preterm vs. term. However, urinary VOCs of women admitted for imminent preterm birth and delivering between 28 + 0 until 36 + 6 weeks compared to women with a high risk for preterm birth during the same gestation period and eventually delivering at term (>37 + 0 weeks) differed significantly (area under the curve: 0.70). In addition, based on the same urinary VOCs, we could identify women with a confirmed chorioamnionitis (area under the curve: 0.72) and urinary tract infection (area under the curve: 0.97). In conclusion, urinary VOCs hold potential for non-invasive, bedside prediction of preterm birth and on the spot identification of intra-uterine infection and urinary tract infections. We suggest these observations are further explored in larger populations.

Hospital antenatal admissions for threatened preterm labor: how long should we be "observing"?

PURPOSE

We sought to describe temporal trends in hospital admissions for threatened preterm labor (TPTL) and to examine hospital admission duration among women delivered or discharged undelivered.

METHODS

We carried out a cohort study on all TPTL admissions among pregnancies with a live singleton fetus and intact membranes between 1999 and 2015 using the United States' Healthcare Cost and Utilization Project-Nationwide Inpatient Sample. ICD-9 codes were used to identify women with TPTL. Duration of antenatal admission length of stay was calculated in days following admission to hospital until delivery ("Delivery Admission") or undelivered discharge ("Observation Admission"). Analyses included evaluating trends of birth admissions over total admissions, identifying predictors of delivery using logistic regression, and measuring risk for delivery with increasing duration of antepartum hospitalization.

RESULTS

Of 15,335,288 pregnancy admissions, 1,089,987 admissions were for TPTL, with 61.8% being 'Delivery Admissions". During the 16-year study period, overall rates of TPTL admissions declined with a rising proportion of admissions being "Delivery Admissions". "Delivery Admissions" were more common among patients who were older, non-Caucasian, obese, or who had placental abruption. "Observation Admissions" were more common among admissions for antepartum hemorrhage or antepartum spotting. Among all "Delivery Admissions" for TPTL, 89% had delivered within 2 days, 7% delivered within 3-6 days, and 5% delivered beyond 6 days.

CONCLUSION

Overall admissions for TPTL declined over the study period with increasing proportions being "Delivery Admissions". Protocols taking into consideration declining risk of preterm birth among patients undelivered after 2 days may be helpful in reducing unnecessary prolonged observation admissions.

Women's experiences of antenatal transfer for threatened premature labour in NSW: A qualitative study

BACKGROUND

Each year thousands of pregnant women experiencing threatened premature labour are transferred considerable distances across Australia to access higher level facilities but only a small proportion of these women go on to actually give birth to a premature baby. Women from regional areas are required to move away from their home, children and support networks because of a perceived risk of birthing in a centre without neonatal intensive care facilities.

AIM

This study examines the experience of women undergoing antenatal transfer for threatened premature labour in New South Wales and the Australian Capital Territory who do not give birth during their transfer admission.

METHODS

Thirteen semi-structured in-depth interviews were held with women across five tertiary referral sites across New South Wales and the Australian Capital Territory, and analysed until saturation for themes.

FINDINGS

Seven urban and six rural women were interviewed. Women and their families were all negatively affected by antenatal transfer. Factors that helped enable a positive experience were; enhanced sense of safety in the tertiary unit, and individual qualities of staff. Factors that contributed to negative experiences were; inadequate and conflicting information, and no involvement or choice in the clinical decision-making process to move to another facility.

CONCLUSIONS

Antenatal transfer is an extremely stressful experience for women and their families. The provision of high quality written and verbal information, and the inclusion of women's perception of risk in the clinical decision making process will improve the experience for women and their families in NSW and the ACT.