American Journal of Obstetrics and Gynecology (2005) 192, 1475–7
www.ajog.org
A review of intrapartum fetal deaths, 1982 to 2002 Fiona M. Mattatall, MD,* Colleen M. O’Connell, PhD, Thomas F. Baskett, MB Department of Obstetrics and Gynaecology, Dalhousie University, Halifax, Nova Scotia, Canada Received for publication August 29, 2004; revised January 10, 2005; accepted January 18, 2005
KEY WORD Intrapartum fetal death
This study identifies cases of unexpected intrapartum fetal deaths over 20 years in a Canadian tertiary hospital. Of 121,659 births, 82 were intrapartum deaths. Eleven fetuses were considered viable and nonanomalous. Six deaths were deemed ideally preventable. Application of electronic fetal heart rate monitoring and rapid operative delivery may reduce the already low rate of intrapartum fetal deaths. Ó 2005 Elsevier Inc. All rights reserved.
Stillbirths include all fetal deaths before birth over 20 weeks gestational age and more than 500 g. Stillbirths may occur antepartum or intrapartum. Scottish data from 1985 to 1996 found a rate of 0.31 per 1000.1 Danish and Swedish rates for 1991 were 4.2 per 1000, and 1.9 per 1000.2 Two studies evaluated intrapartum fetal deaths over time. Northern Norway showed a reduction from 3.4 per 1000 (1976 to 1980) to 1.0 per 1000 (1992 to 1997).3 Finland showed a similar trend with rates of 1.7 per 1000 (1970 to 1972) and 0.3 per 1000 (1979 to 1981).4 Interestingly, over this time frame, electronic fetal heart rate (FHR) monitoring increased from 9% of parturients to 95%, suggesting that monitoring may have prevented some fetal deaths. Risk factors for intrapartum fetal deaths include malpresentation, abruptio placentae, and cord prolapse.5 One study suggested that risk of stillbirth related to intrapartum asphyxia is highest on weekends.6
Table I
Fetal deaths (O500 g and/or O20 wk)
Fetal deaths Antepartum Prior to admission After admission Unknown Intrapartum Previable Major anomaly Viable
Number
Rate
835 753 434 67 252 82 51 20 11
6.9/1000 6.2/1000
0.67/1000
0.09/1000
The purpose of the current study was to identify and review cases of unexpected intrapartum fetal death in one tertiary level maternity hospital.
Material and methods
Supported by the H. B. Atlee Endowment Fund. * Reprint requests: F. M. Mattatall, IWK Health Centre, 5850 University Avenue, Halifax, Nova Scotia B3K 6R8, Canada. E-mail: fi
[email protected] 0002-9378/$ - see front matter Ó 2005 Elsevier Inc. All rights reserved. doi:10.1016/j.ajog.2005.01.049
All deliveries at the Women’s Hospital, IWK Health Centre between January 1, 1982, and December 31, 2002, were included in the study. During this period livein 24-hour consultant anesthesia and obstetric services were available. Cases of fetal death were identified from
1476
Mattatall, O’Connell, and Baskett
Table II
Intrapartum fetal deaths (viable, nonanomalous)
Maternal Gravida/ Case age (y) para 1
26
4/2
2
18
1/0
3
27
1/0
4
20
1/0
5
29
2/0
6
22
2/1
7
22
3/2
8
41
7/4
9 10
24 37
1/0 1/0
11
31
1/0
Antenatal risk factors
Birth weight (g)
Decision to delivery Gender (min)
Mode of Delivery
38
3400
M
12
Cesarean Normal
41
3105
F
15
42
3516
M
N/A
Cesarean Single umbilical artery Forceps Abruptio
37
2560
M
14
40
3220
F
20
Uncertain
2925
F
0
26
810
M
8
33
4900
M
55
Cesarean Nonimmune hydrops
41 32
3730 1876
F F
6 34
26
780
M
N/A
Forceps Normal Cesarean Velamentous cord insertion Vaginal Abruptio
Intrapartum risk Gestational factors age (wks)
No antenatal care Meconium Nuchal cord None PROM Meconium, Nuchal cord Obese Meconium Nuchal cord Abruptio Vaginal bleed Malpresentation third trimester Smoker Meconium Vaginal bleed second trimester No antenatal care Meconium Preeclampsia Nuchal cord Vaginal bleed Malpresentation first trimester Abruptio Blood transfusion Oligohydramnios Preeclampsia/ None HELLP Hydrops fetalis None Meconium None Vaginal bleeding No antenatal care Vaginal bleeding
Autopsy
Cesarean Not performed Cesarean Normal
Vaginal
Placental infarction Cesarean Abruptio
PROM, Premature rupture of membranes; HELLP, hemolysis, elevated liver enzymes, and low platelets.
the Nova Scotia Atlee Perinatal Database, which registers antenatal, intrapartum, and postpartum information on all births in Nova Scotia. Only normal, mature fetuses that entered labor alive but died while under medical care were included. Previable fetuses and those with major anomalies were excluded. The definition of ‘‘viability’’ changed over the study period, so we excluded cases in which obstetrical intervention was withheld on behalf of the fetus.
Results Between 1982 and 2002, there were 121,659 births at the Women’s Hospital, IWK Health Centre. Of these, 835 were fetal deaths (6.9 per 1000). Eighty-two intrapartum deaths were reviewed (Table I). Of these, 11 were identified as viable and nonanomalous (Table II). Fifty-one previable fetuses ranged from 19 to 25 weeks and 235 to 930 g. Twenty fetuses were anomalous (multiple anomalies, 8; severe intrauterine growth restriction, 5; anencephaly, 2; bilateral renal agenesis, 2;
trisomy 18, 1; nonimmune hydrops, 1; Walker-Warburg syndrome, 1). We deemed six cases ideally preventable: 1. Case 4: patient was discharged after FHR monitoring that, in retrospect, was nonreassuring. She returned 16 hours later in labor with a more ominous FHR tracing. 2. Case 5: FHR was confirmed by intermittent auscultation at admission and then not for another 2 hours. FHR could not be confirmed following amniotomy for thick meconium. 3. Case 8: time from decision to delivery was 55 minutes. 4. Case 9: FHR was auscultated briefly on admission and then not for another 3 hours. FHR could not be confirmed following amniotomy for thick meconium. 5. Case 10: time from decision to delivery was 34 minutes. 6. Case 11: FHR was auscultated intermittently on admission. One hour later medical staff questioned
Mattatall, O’Connell, and Baskett whether the FHR was being mistaken for maternal pulse. Amniotomy was performed for bloody fluid and fetal demise was confirmed by ultrasound.
1477 delivery more than 30 minutes from decision. In fact, this group found only 59% of emergency cesarean deliveries were in compliance with this American College of Obstetrics and Gynecology guideline.10
Comment In our hospital, the intrapartum fetal death rate of 0.67 per 1000 is in keeping with literature reports. Unexpected intrapartum fetal deaths are rare (0.09 per 1000). Of the reviewed cases, the numbers are too small to comment on trends mentioned in the literature. Five of the deaths were deemed nonpreventable. In all cases, the diagnosis of fetal distress was acted upon promptly. Two cases were of abruptio placenta, 1 of a 35% placental infarction, 1 fetus had a single umbilical artery with cord entanglement, and 1 case remains without a cause of death. Four of the deaths may have been prevented with improved FHR monitoring and interpretation. Fetal distress would likely have been identified earlier had extended FHR monitoring at admission or appropriate monitoring after admission been performed. There is currently insufficient evidence, however, to show that FHR monitoring admission tests improve fetal outcomes. The Society of Obstetricians and Gynaecologists of Canada suggest assessment of FHR every 15 to 30 minutes in the active phase of labor in low-risk cases.7 Two of the intrapartum deaths may have been prevented with more prompt operative delivery. Although there is no recognized North American standard for speed of operative delivery, the American College of Obstetrics and Gynecology recommends that facilities be able to perform cesarean delivery within 30 minutes.8 Chauhan et al9 have since demonstrated that there is no increased risk for adverse neonatal outcome with
References 1. Gordon CS, Smith MD. Life-table analysis of the risk of perinatal death at term and post term in singleton pregnancies. Am J Obstet Gynecol 2001;184:489-6. 2. Westergaard HB, Kanghoff-Roos J, Larsen S, Borch-Christensen H, Lindmark G. Intrapartum death of nonmalformed fetuses in Denmark and Sweden in 1991. A perinatal audit. Acta Obstet Gynecol Scand 1997;76:959-63. 3. Dahl LB, Berge LN, Dramsdahl H, Vermeer A, Huurnink A, Kaaresen PI, Oian P. Antenatal, neonatal and post neonatal deaths evaluated by medical audit. A population-based study in northern Norwayd1976 to 1997. Acta Obstet Gynecol Scand 2000;79:1075-82. 4. Erkkola R, Gronroos M, Punnonen R, Kikku P. Analysis of intrapartum fetal deaths: their decline with increasing electronic fetal monitoring. Act Obstet Gynecol Scand 1984;63:459-62. 5. Aessandri LM, Stanley FJ, Read AW. A case-control study of intrapartum stillbirths. Br J Obstet Gynaecol 1992;99:719-23. 6. Luo ZC, Liu S, Wilkings, Kramer MS. Risks of stillbirth and early neonatal death by day of the week. CMAJ 2004;170:337-41. 7. Society of Obstetrician and Gynaecologists of Canada: Fetal health surveillance in labor. Clinical Practice Guideline No. 112, March 2002. 8. American College of Obstetricians and Gynecologists. Guidelines for Perinatal Care. Washington, DC: American College of Obstetricians and Gynecologists; 1992. 9. Chauhan SP, Roach H, Naef RW, Magann EF, Morrison JC, Martin JN. Cesarean section for suspected fetal distress. Does the decision-incision time make a difference? J Reprod Med 1997;42:347-52. 10. Chauhan SP, Magann EF, Scott JR, Scardo JA, Hendrix NW, Martin JN. Emergency cesarean delivery for nonreassuring fetal heart rate tracings: Compliance with ACOG guidelines. J Reprod Med 2003;48:975-81.
