Distinguishing Fetal Death, Stillbirth May Help Prevent Both

Diana Swift

March 11, 2015

The last decade has seen increased interest in stillbirth and fetal death, with research and public health efforts aimed at prevention. To this end, there is an effort underway to replace the anachronistic 1950s definition of fetal death with a more modern one to distinguish between the timing of stillbirth and that of fetal death, which is clinically more significant.

Recent advances in imaging technology have facilitated the antenatal diagnosis of fetal death and brought this issue to the fore.

"An international consensus is needed to standardize the definition of reportable fetal deaths," write K.S. Joseph, MD, PhD, from Children's and Women's Hospital and Health Centre of British Columbia and the University of British Columbia, Vancouver, Canada, and colleagues in an article published in the April issue of Obstetrics & Gynecology. "[I]deally this should be based on the timing of fetal death and should address the status of pregnancy terminations."

Among other suggestions, they recommend that fetal death certificates document gestational age at death as in stillbirth. They also call for a consensus on the treatment of fetal deaths resulting from pregnancy terminations and recommend that the healthcare system, not parents, take final responsibility for registration.

Commonly, "stillbirth" refers to the delivery of a viable fetus born dead, whereas "fetal death" refers to the death of a fetus before delivery. Often the terms are used synonymously, as obstetrician-gynecologist Marc Jackson, MD, MBA, from the Department of Maternal and Fetal Medicine at Intermount Health Care and the University of Utah, Salt Lake City, points out in an accompanying editorial. Many countries did not even have a requirement to register stillbirths until the late 19th or early 20th centuries.

Focusing on fetal death, Dr Joseph and colleagues note that although the timing of stillbirth is important for maternal care, information on fetal death has more etiologic and prognostic significance than gestational age at stillbirth. "[S]tudies show that the risk of fetal death is affected by the gestational age at which fetal death occurred in the previous pregnancy," they write. They note that the emphasis on gestational age at stillbirth in vital records is an anachronism from an age when it was impossible to identify the time of fetal death with any accuracy.

Dr Jackson points out that definitions of stillbirth remain a semantic patchwork across US states and other countries. Although the Centers for Disease Control and Prevention and the American College of Obstetrics and Gynecology define stillbirth as a gestational age of 20 weeks or more or a birth weight of 350 g or more at delivery, there are at least nine different reporting criteria from different states. Internationally, the World Health Organization recommends reporting stillbirths after 28 weeks' gestation, with a birth a weight of 1000 g or more or a fetal length of at least 35 cm. In Europe and Scandinavia, at least 10 different definitions are still in use.

As for fetal deaths, the World Health Organization's criteria call for the inclusion in fetal death statistics of fetuses weighing 500 g or more, and absent information on weight, the use of a gestational age of 22 weeks or more and a body length of at least 25 cm. Highlighting the lack of international consensus, North American reporting criteria suggest earlier cut-offs: in 12 US states, the threshold is 350 g or at least 20 weeks' gestation. "Thus, a fetal death with a birth weight of 499 g and a gestational age at delivery of 22 weeks would not be deemed a reportable fetal death under [World Health Organization] criteria but would require registration in countries such as Canada and the United States," the researchers write. In Spain, the gestational age cut-off is 26 weeks; in Italy, it is 180 days.

Furthermore, high-income countries vary as to the requirement for including pregnancy terminations in fetal deaths or stillbirths. In Canada, the United Kingdom, and Australia, pregnancy terminations must be included in fetal deaths or stillbirths, but not in the United States, Sweden, or Italy.

Dr Joseph and colleagues note that in Canada, the majority of fetal deaths are a result of pregnancy terminations. "[R]ecent increases in pregnancy termination after prenatal diagnosis of congenital anomalies have led to a secular increase in fetal death rates," they write. "This highlights the need to distinguish pregnancy terminations from spontaneous fetal deaths for public health surveillance purposes, and several countries require separate registration for the two events."

Dr Joseph told Medscape Medical News that the need to distinguish between terminations and spontaneous deaths was one of the reasons he and his colleagues decided to write their current article.

Another impetus, he said, was that "my nursing colleagues have repeatedly encountered incidents involving stillbirths where procedural issues compromise clinical care of the mother." He added that the contemporary stillbirth registration process is modeled after birth, rather than death registration.

As new technology meets old definitions, an incongruity emerges in the practice of fetal reduction in multifetal pregnancy. Although most reproductive specialists would not deem the reduction of a triplet pregnancy to a twin pregnancy at 10 to 13 weeks' gestation a fetal death, registration criteria in Australia, Canada, and New Zealand require it. In some countries, the reductions, Dr Joseph said, would need to be registered and "delivered," and burial permits are required even though the fetal remains cannot be identified.

"Unfortunately, this requirement...may cause undue psychological stress for some parents, because it constitutes the creation of a permanent public document and also makes them relive the original anguish associated with the fetal reduction," the authors write.

They propose the following steps to improve the situation:

  • Fetal death registration should document the gestational age at fetal death, based on best expert assessment, in addition to age at stillbirth, with the latter used as age at fetal death if this is uncertain.

  • Criteria for fetal death registration should be based on gestational age at fetal death.

  • Consensus should be sought on whether the definition of fetal death should exclude pregnancy terminations that meet the reportable fetal death definition, and these should be reported separately from spontaneous deaths.

  • Fetal deaths from selective reduction in multifetal pregnancies should not require registration as fetal deaths but might require registration as pregnancy terminations.

  • The onus for fetal death registration and burial arrangements should default to the healthcare provider/institution, whereas parents should be supported in their choice to be involved or not.

Dr Jackson, focusing on stillbirth, also stresses the need to move forward on consensus. "It is only with dialogue and agreement on basic definitions and data collection that we will be able to begin to come together to tackle the worldwide tragedy of stillbirth," he writes.

The study authors are supported by awards from the Child and Family Research Institute and the Michael Smith Foundation for Health Research, Children's and Women's Hospital and Health Centre of British Columbia, and the Canadian Institutes of Health Research, Ottawa. The authors and the editorialists have disclosed no relevant financial relationships.

Obstet Gynecol. 2015;125:782-788.

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....