Risk of preterm birth after prior term cesarean

Peer reviewedPublisher PD

Birth weight ratio as an alternative to birth weight percentile to express infant weight in research and clinical practice: a nationwide cohort study

Research articleObjective. To compare birth weight ratio and birth weight percentile to express infant weight when assessing pregnancy outcome. Study Design. We performed a national cohort study. Birth weight ratio was calculated as the observed birth weight divided by the median birth weight for gestational age. The discriminative ability of birth weight ratio and birth weight percentile to identify infants at risk of perinatal death (fetal death and neonatal death) or adverse pregnancy outcome (perinatal death + severe neonatal morbidity) was compared using the area under the curve. Outcomes were expressed stratified by gestational age at delivery separate for birth weight ratio and birth weight percentile. Results. We studied 1,299,244 pregnant women, with an overall perinatal death rate of 0.62%. Birth weight ratio and birth weight percentile have equivalent overall discriminative performance for perinatal death and adverse perinatal outcome. In late preterm infants (33(+0)-36(+6) weeks), birth weight ratio has better discriminative ability than birth weight percentile for perinatal death (0.68 versus 0.63, P  0.01) or adverse pregnancy outcome (0.67 versus 0.60, P < 0.001). Conclusion. Birth weight ratio is a potentially valuable instrument to identify infants at risk of perinatal death and adverse pregnancy outcome and provides several advantages for use in research and clinical practice. Moreover, it allows comparison of groups with different average birth weights.Bart Jan Voskamp, Brenda M. Kazemier, Ewoud Schuit, Ben Willem J. Mol, Maarten Buimer, Eva Pajkrt and Wessel Ganzevoor

Laparoscopic umbilical hernia repair in the presence of extensive paraumbilical collateral veins: A case report

A patient with an umbilical hernia presenting with collateral veins in the abdominal wall and umbilicus is a case that every hernia surgeon has to deal with occasionally. Several underlying diseases have been described to provoke collateral veins in the abdominal wall. However, the treatment strategy should be uniform. We herein report a case of a successful laparoscopic umbilical hernia repair in a patient with collateral veins in the abdominal wall and umbilicus. A 63-year-old man was referred to the surgical outpatient clinic with a large symptomatic umbilical hernia and collateral veins in the abdominal wall, secondary to an occlusion of both common iliac veins. Because of collateral veins in the umbilicus and the size of the hernial defect, he was offered laparoscopic hernia repair without compromising these veins. Because of the extensive abdominal wall collaterals, duplex sonography vein mapping was performed preoperatively to mark a safe collateral-free area for trocar introduction. The defect was repaired by mesh prosthesis

The predictive capacity of uterine artery Doppler for preterm birth - a cohort study

Introduction: Mid‐trimester uterine artery resistance measured with Doppler sonography is predictive for iatrogenic preterm birth. In view of the emerging association between hypertensive disease in pregnancy and spontaneous preterm birth, we hypothesized that uterine artery resistance could also predict spontaneous preterm birth. Material and methods: We performed a cohort study of women with singleton pregnancies. Uterine artery resistance was routinely measured at the 18‐22 weeks anomaly scan. Pregnancies complicated by congenital anomalies or intrauterine fetal death were excluded. We analyzed if the waveform of the uterine artery (no notch, unilateral notch or bilateral notch) was predictive for spontaneous and iatrogenic preterm birth, defined as delivery before 37 weeks of gestation. Furthermore, we assessed whether the uterine artery pulsatility index was associated with the risk of preterm birth. Results: Between January 2009 and December 2016 we collected uterine Doppler indices and relevant outcome data in 4521 women. Mean gestational age at measurement was 19+6 weeks. There were 137 (3.0%) women with a bilateral and 213 (4.7%) with a unilateral notch. Mean gestational age at birth was 38+6 weeks. Spontaneous and iatrogenic preterm birth rates were 5.7% and 4.9%, respectively. Mean uterine artery resistance was 1.12 in the spontaneous preterm birth group compared with 1.04 in the term group (P = 0.004). The risk of preterm birth was increased with high uterine artery resistance (OR 2.9 per unit; 95% CI 2.4‐3.9). Prevalence of spontaneous preterm birth increased from 5.5% in women without a notch in the uterine arteries to 8.0% in women with a unilateral notch and 8.0% in women with a bilateral notch. For iatrogenic preterm birth, these rates were 3.9%, 13.6% and 23.4%, respectively. Likelihood ratios for the prediction of spontaneous preterm birth were 1.6 (95% CI 1.0‐2.6) and 1.9 (95% CI 1.0‐3.5) for unilateral and bilateral notches, respectively, and for iatrogenic preterm birth they were 3.6 (95% CI 2.5‐5.2) and 6.8 (95% CI 4.7‐9.9) for unilateral and bilateral notches, respectively. Of all women with bilateral notching, 31.4% delivered preterm. Conclusions: Mid‐trimester uterine artery resistance measured at 18‐22 weeks of gestation is a weak predictor of spontaneous preterm birth.Maud D. van Zijl, Bouchra Koullali, Ben W.J. Mol, Rosalinde J. Snijders, Brenda M. Kazemier, Eva Pajkr

Emergency repair of inguinal hernia in the premature infant is associated with high direct medical costs

_Purpose:_ Inguinal hernia repair is frequently performed in premature infants. Evidence on optimal management and timing of repair, as well as related medical costs is still lacking. The objective of this study was to determine the direct medical costs of inguinal hernia, distinguishing between premature infants who had to undergo an emergency procedure and those who underwent elective inguinal hernia repair. _Methods:_ This cohort study based on medical records concerned premature infants with inguinal hernia who underwent surgical repair within 3 months after birth in a tertiary academic children’s hospital between January 2010 and December 2013. Two groups were distinguished: patients with incarcerated inguinal hernia requiring emergency repair and patients who underwent elective repair. Real medical costs were calculated by multiplying the volumes of healthcare use with corresponding unit prices. Nonparametric bootstrap techniques were used to derive a 95 % confidence interval (CI) for the difference in mean costs. _Results:_ A total of 132 premature infants were included in the analysis. Emergency surgery was performed in 29 %. Costs of hospitalization comprised 65 % of all costs. The total direct medical costs amounted to €7418 per premature infant in the emergency repair group versus €4693 in the elective repair group. Multivariate analysis showed a difference in costs of €1183 (95 % CI −1196; 3044) in favor of elective repair after correction for potential risk factors. _Conclusion:_ Emergency repair of inguinal hernia in premature infants is more expensive than elective repair, even after correction for multiple confounders. This deserves to b

Kinetic Characterisation of a Single Chain Antibody against the Hormone Abscisic Acid: Comparison with Its Parental Monoclonal

A single-chain Fv fragment antibody (scFv) specific for the plant hormone abscisic acid (ABA) has been expressed in the bacterium Escherichia coli as a fusion protein. The kinetics of ABA binding have been measured using surface plasmon resonance spectrometry (BIAcore 2000) using surface and solution assays. Care was taken to calculate the concentration of active protein in each sample using initial rate measurements under conditions of partial mass transport limitation. The fusion product, parental monoclonal antibody and the free scFv all have low nanomolar affinity constants, but there is a lower dissociation rate constant for the parental monoclonal resulting in a three-fold greater affinity. Analogue specificity was tested and structure-activity binding preferences measured. The biologically-active (+)-ABA enantiomer is recognised with an affinity three orders of magnitude higher than the inactive (-)-ABA. Metabolites of ABA including phaseic acid, dihydrophaseic acid and deoxy-ABA have affinities over 100-fold lower than that for (+)-ABA. These properties of the scFv make it suitable as a sensor domain in bioreporters specific for the naturally occurring form of ABA