Development of a comprehensive database for research on foetal acidosis

OBJECTIVE

To develop a research database for mother-and-child clinical and laboratory data and digital foetal heart rate (FHR) recordings.

METHODS

The Base Bien Naître (BBN) database was derived from a single-centre health data warehouse. It contains exhaustive data on all parturients with a singleton pregnancy, a vaginal or caesarean delivery in labour with a cephalic presentation after at least 37 weeks of amenorrhea, and a live birth between February 1st, 2011, and December 31st, 2018. On arrival in the delivery room, the FHR was recorded digitally for at least 30 min. A cord blood sample was always taken in order to obtain arterial pH (pHa). More than 6,000 recordings were analyzed visually for the risk of foetal acidosis and classified into five groups (according to the French College of Gynaecologists and Obstetricians (CNGOF) classification) or three groups (according to the International Federation of Gynaecology and Obstetrics (FIGO) classification).

RESULTS

Of the 16,089 files in the health data warehouse, 11,026 were complete and met the BBN's inclusion criteria. The FHR digital recordings were of good quality, with low signal loss (median [interquartile range]: 7.0% [4.3;10.9]) and a median recording time of 304 min [190;438]). In 3.7% of the children, the pHa was below 7.10. We selected a subset of 6115 records with good-quality FHR recordings over 120 min and reliable cord blood gas data: 692 (11.3%) had at least a significant risk of acidosis (according to the CNGOF classification), and 1638 (26.8%) were at least suspicious (according to the FIGO classification).

CONCLUSION

The BBN database has been designed as a searchable tool with data reuse. It currently contains over 11,000 records with comprehensive data.

Use of automated fetal heart rate analysis to identify risk factors for umbilical cord acidosis at birth

OBJECTIVE

To identify clinical parameters and intrapartum fetal heart rate parameters associated with a risk of umbilical cord acidosis at birth, using an automated analysis method based on empirical mode decomposition.

METHODS

Our single-center study included 381 cases (arterial cord blood pH at birth pHa ≤7.15) and 1860 controls (pHa ≥7.25) extracted from a database comprising 8,383 full datasets for over-18 mothers after vaginal or caesarean non-twin, non-breech deliveries at term (>37 weeks of amenorrhea). The analysis of a 120-min period of the FHR recording (before maternal pushing or the decision to perform a caesarean section during labor) led to the extraction of morphological, frequency-related, and long- and short-term heart rate variability variables. After univariate analyses, sparse partial least square selection and logistic regression were applied.

RESULTS

Several clinical factors were predictive of fetal acidosis in a multivariate analysis: nulliparity (odds ratio (OR) 95% confidence interval (CI)]: 1.769 [1.362-2.300]), a male fetus (1.408 [1.097-1.811]), and the term of the pregnancy (1.333 [1.189-1.497]). The risk of acidosis increased with the time interval between the end of the FHR recording and the delivery (OR [95%CI] for a 1-min increment: 1.022 [1.012-1.031]). The risk factors related to the FHR signal were mainly the difference between the mean baseline and the mean FHR (OR [95%CI]: 1.292 [1.174-1.424]), the baseline range (1.027 [1.014-1.040]), fetal bradycardia (1.038 [1.003-1.075]) and the late deceleration area (1.002 [1.000-1.005]). The area under the curve for the multivariate model was 0.79 [0.76; 0.81].

CONCLUSION

In addition to clinical predictors, the automated FHR analysis highlighted other significant predictors, such as the baseline range, the instability of the FHR signal and the late deceleration area. This study further extends the routine application of automated FHR analysis during labor and, ultimately, contributes to the development of predictive scores for fetal acidosis.

[Antenatal screening for congenital heart disease: a retrospective analysis of 20 years of experience]

BACKGROUND

Congenital heart disease is often severe and outcome remains uncertain. In some cases, early intervention at birth can improve the prognosis. Prenatal detection of congenital heart disease by ultrasound may improve outcome for foetuses with congenital heart disease but today, results are not convincing. The purpose of this review was to describe the detection of congenital heart disease in a non selected population.

METHODS

A retrospective study was undertaken to evaluate the prenatal detection of congenital heart disease in our department from 1984 to 2003.

RESULTS

Incidence of congenital heart disease was 4.9. Sensitivity of detection was 60%, specificity was 99.9%. Most cases were severe heart diseases. In 57 fetuses (40%), congenital heart disease was not detected. Thirty-seven fetuses (65%) presented minor disease; in 20 fetuses (35%), congenital heart disease was found to be severe. Effectiveness of detection of major congenital heart diseases has increased since 2000.

CONCLUSION

Large-scale fetal heart screening is necessary for early detection of congenital heart disease and improved outcome.

[Children of hyper- and hypothyroid mothers]

A multicenter study was able to utilize 120 medical files of children born from mothers who presented an abnormal thyroid function, 67 euthyroid goiters, 29 hyperthyroidisms, and 24 hypothyroidisms. In the first case, whether or not an inhibiting treatment was initiated, all children were perfectly normal. In case of maternal hyperthyroidism, the risk of malformations is not increased, deaths in utero and mostly in utero growth delays (1 case in 2) are more frequent. At birth, the child may present a hyperthyroidism due to the effect of SAT with elevated TSH and a goiter, sometimes compressing and impairing breathing, or also a hyperthyroidism due to transplacental crossing of stimulating immunoglobulins with possibility of thyreotoxic crises and heart failure. The diagnosis could be made in utero in the presence of tachycardia or with T4 and TSH assays in the cord. In case of maternal hypothyroidism, usually the children have no problems and the risk of neonatal hypothyroidism is mostly present in premature infants if the maternal balance is poor (2 in 24 cases in our series). Finally, in the reference population, the risk of neonatal hypothyroidism remains 1 in 3600 and justifies systematic screening on the 5th day of life.