++
Determining the cause of fetal death aids maternal psychological adaptation to a significant loss, helps assuage the guilt that is part of grieving, permits more accurate counseling regarding recurrence risk, and may prompt therapy or intervention to prevent a similar outcome in the next pregnancy (American College of Obstetricians and Gynecologists, 2012). Identification of inherited syndromes also provides useful information for other family members.
++
Important tests in stillbirth evaluation are neonatal autopsy and karyotyping and examination of the placenta, cord, and membranes (Pinar, 2014). An algorithm provided by the American College of Obstetricians and Gynecologists (2012) is shown in Figure 35-5. A thorough examination of the fetus, placenta, and membranes is recommended at delivery, with careful documentation in the medical record. The details of relevant prenatal events should be provided. Photographs should be taken whenever possible, and a full radiograph of the fetus—a fetogram—may be performed. Magnetic resonance (MR) imaging and sonography may be especially important in providing anatomical information if parents decline a full autopsy.
++
+++
Laboratory Evaluation
++
If autopsy and chromosomal studies are performed, up to 35 percent of stillborns are discovered to have major structural anomalies (Faye-Petersen, 1999). Approximately 20 percent have dysmorphic features or skeletal abnormalities, and 8 percent have chromosomal abnormalities (Pauli, 1994; Saller, 1995). The American College of Obstetricians and Gynecologists (2012) recommends karyotyping all stillborns. Reddy and coworkers (2012) have recently reported that microarray analysis is more likely than karyotype analysis to provide a genetic diagnosis, primarily because of its success with nonviable tissue. In the absence of morphological anomalies, up to 5 percent of stillborns will have a chromosomal abnormality (Korteweg, 2008).
++
Appropriate consent must be obtained to take fetal tissue samples, including fluid obtained postmortem by needle aspiration. A total of 3 mL of fetal blood, obtained from the umbilical cord or by cardiac puncture, is placed into a sterile, heparinized tube for cytogenetic studies. If blood cannot be obtained, the American College of Obstetricians and Gynecologists (2012) recommends at least one of the following samples: (1) a placental block measuring about 1 × 1 cm taken below the cord insertion site in the unfixed specimen; (2) umbilical cord segment approximately 1.5 cm long; or (3) internal fetal tissue specimen such as costochondral junction or patella. Importantly, skin is no longer recommended for a tissue sample. Tissue is washed with sterile saline before being placed in lactated Ringer solution or sterile cytogenetic medium. Placement in formalin or alcohol kills remaining viable cells and prevents cytogenetic analysis.
++
A full karyotype may not be possible in cases with prolonged fetal death. For example, Korteweg and associates (2008) reported that they successfully performed cytogenetic analysis in only a third of macerated fetuses. Fluorescence in situ hybridization might be used to exclude numerical abnormalities or to document certain common deletions such as that causing DiGeorge syndrome. Maternal blood should be obtained for Kleihauer-Betke staining; for antiphospholipid antibody and lupus anticoagulant testing if indicated; and for serum glucose measurement to exclude overt diabetes (Silver, 2013).
++
Parents should be offered and encouraged to allow a full autopsy. However, valuable information can still be obtained from limited studies. Pinar and colleagues (2012) described the autopsy protocol used by the Stillbirth Collaborative Research Network. In the absence of an autopsy, a gross external examination combined with photography, radiography, MR imaging, bacterial cultures, and selective use of chromosomal and histopathological studies often can aid determination of the cause of death.
++
A complete autopsy is more likely to yield valuable information. An analysis of 400 consecutive fetal deaths in Wales found that autopsy altered the presumed cause of death in 13 percent and provided new information in another 26 percent (Cartlidge, 1995). Other investigators have shown that autopsy results changed the recurrence risk estimates and parental counseling in 25 to 50 percent of cases (Faye-Petersen, 1999; Silver, 2007).
++
According to the survey by Goldenberg and coworkers (2013), most hospitals do not audit stillbirths. In other centers, however, maternal records and autopsy findings are reviewed on a monthly basis by a stillbirth committee composed of obstetricians, maternal-fetal medicine specialists, neonatologists, clinical geneticists, and perinatal pathologists. If possible, the cause of death is assigned based on available evidence. Most importantly, parents should then be contacted and offered counseling regarding the reason for death, the recurrence risk if any, and possible strategies to avoid recurrence in future pregnancies.