The Current Crisis in Obstetrics

Open access intrapartum CTG database

Background

Cardiotocography (CTG) is a monitoring of fetal heart rate and uterine contractions. Since 1960 it is routinely used by obstetricians to assess fetal well-being. Many attempts to introduce methods of automatic signal processing and evaluation have appeared during the last 20 years, however still no significant progress similar to that in the domain of adult heart rate variability, where open access databases are available (e.g. MIT-BIH), is visible. Based on a thorough review of the relevant publications, presented in this paper, the shortcomings of the current state are obvious. A lack of common ground for clinicians and technicians in the field hinders clinically usable progress. Our open access database of digital intrapartum cardiotocographic recordings aims to change that.

Description

The intrapartum CTG database consists in total of 552 intrapartum recordings, which were acquired between April 2010 and August 2012 at the obstetrics ward of the University Hospital in Brno, Czech Republic. All recordings were stored in electronic form in the OB TraceVue®;system. The recordings were selected from 9164 intrapartum recordings with clinical as well as technical considerations in mind. All recordings are at most 90 minutes long and start a maximum of 90 minutes before delivery. The time relation of CTG to delivery is known as well as the length of the second stage of labor which does not exceed 30 minutes. The majority of recordings (all but 46 cesarean sections) is – on purpose – from vaginal deliveries. All recordings have available biochemical markers as well as some more general clinical features. Full description of the database and reasoning behind selection of the parameters is presented in the paper.

Conclusion

A new open-access CTG database is introduced which should give the research community common ground for comparison of results on reasonably large database. We anticipate that after reading the paper, the reader will understand the context of the field from clinical and technical perspectives which will enable him/her to use the database and also understand its limitations.

Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United States

OBJECTIVE

To examine the association between electronic fetal heart rate monitoring and neonatal and infant mortality, as well as neonatal morbidity.

STUDY DESIGN

We used the United States 2004 linked birth and infant death data. Multivariable log-binomial regression models were fitted to estimate risk ratio for association between electronic fetal heart rate monitoring and mortality, while adjusting for potential confounders.

RESULTS

In 2004, 89% of singleton pregnancies had electronic fetal heart rate monitoring. Electronic fetal heart rate monitoring was associated with significantly lower infant mortality (adjusted relative risk, 0.75); this was mainly driven by the lower risk of early neonatal mortality (adjusted relative risk, 0.50). In low-risk pregnancies, electronic fetal heart rate monitoring was associated with decreased risk for Apgar scores <4 at 5 minutes (relative risk, 0.54); in high-risk pregnancies, with decreased risk of neonatal seizures (relative risk, 0.65).

CONCLUSION

In the United States, the use of electronic fetal heart rate monitoring was associated with a substantial decrease in early neonatal mortality and morbidity that lowered infant mortality.

Decreasing diagnoses of birth asphyxia in Canada: fact or artifact

OBJECTIVE

We assessed temporal trends in birth asphyxia in Canada, to determine whether changes were real or secondary to changes in coding.

METHODS

We used data from the Canadian Institute for Health Information Discharge Abstract Database to study the national incidence of birth asphyxia, by using International Classification of Diseases codes. We also studied birth asphyxia by using data from the Nova Scotia Atlee Perinatal Database. In the Nova Scotia Atlee Perinatal Database, we defined a case of birth asphyxia as a live birth with an Apgar score at 5 minutes of < or =3, depression at birth requiring resuscitation with a mask for > or =3 minutes and/or intubation, or neonatal postasphyctic seizures.

RESULTS

Nationally, between 1991 and 2005, the incidence of birth asphyxia decreased significantly, from 43.8 to 2.4 cases per 1000 live births. The rate of decrease was highest between 1991 and 1998, corresponding to a period when strict Canadian and international criteria for the diagnosis of birth asphyxia were published. By comparison, neither national rates of related diagnoses nor Nova Scotia birth asphyxia rates, which ranged from 8.8 to 14.3 cases per 1000 live births, showed evidence of a decrease during the study period.

CONCLUSIONS

Comparisons of national trends in birth asphyxia diagnoses and trends in conditions associated with birth asphyxia, both nationally and in Nova Scotia, suggest that the dramatic decrease in the diagnosis of birth asphyxia is an artifact of changes in the use of International Classification of Diseases coding associated with the publication of stricter diagnostic definitions of birth asphyxia. We conclude that International Classification of Diseases codes are not useful for surveillance of birth asphyxia.