Electricity

Risk Factor: D
Class: Miscellaneous

Contents of this page:

Fetal Risk Summary

Published reports have described the exposure of pregnant women to electric currents through five different means: accidental electric injury in the home, lightning strikes, electroconvulsive therapy, antiarrhythmic direct-current cardioversion, and from a Taser weapon. Dramatically different fetal outcomes have occurred based on the type of exposure.

Four reports involving 14 women described accidental electric shock with alternating current, either 110 volts or 220 volts, from appliances or wiring in the home (1,2,3 and 4). In each of the cases, the electric current took a presumed hand-to-foot pattern through the body and, thus, probably through the uterus. Gestational ages varied from 1240 weeks. Although none of the mothers was injured or even lost consciousness, in these otherwise harmless events, fetal death occurred in 10 (71%). In at least five of the cases, immediate cessation of fetal movements was noted. One mother, who received the shock at about 28 weeks' gestation, subsequently developed hydramnios and delivered an infant 4 weeks later (1). Burn marks were evident on the newborn, who died 3 days after birth. A second growth-retarded infant was stillborn at 33 weeks' gestation, 12 weeks after the electrical injury (4). In most cases, no specific clinical or pathologic signs could be noted (4). However, oligohydramnios was observed in 2 cases in which the fetuses survived (4). The accidents occurred at 20 and 32 weeks' gestation, with injury-to-delivery intervals of 6 and 21 weeks, respectively. The specific cause of fetal damage has not been determined. It may be due to changes in fetal heart conduction resulting in cardiac arrest (3,4) or by lesions in the uteroplacental bed (4).

A 1997 paper described 20 cases from the literature of electric shock during pregnancy with healthy newborn outcomes occurring in only 5 cases (5). The authors of this report then described the outcomes of 31 women studied prospectively after exposure to home appliances with 110 V (N=26) or 220 V (N=2), or to high voltage (2000 and 8000 V) from electrified fences (N=2), or to a low- voltage (12 V) telephone line (N=1).(An abstract of their preliminary findings was published in 1995 [6]). An additional 16 women who had received electric shocks during pregnancy were either lost to follow-up (N=10) or had not yet given birth (N=6). Of the 31 outcomes, there were 2 spontaneous abortions, one of which may have been caused by the electric shock. In that case, the abortion occurred 2 weeks after the mother had received the shock. One of the live newborns had a ventricular septal defect that eventually closed spontaneously. In comparison to the group of 20 cases from the literature, there were significant differences discovered in the number of live births (94% vs. 25%), voltage involved (77% to 110 V vs. 76% to 220 V), and current crossing the uterus (i.e., hand-to-foot transmission suggesting that the current crossed the uterus) (10% vs. 62%).

Lightning strikes of pregnant women are rare, with only 12 cases described since 1833 (1,7,8,9,10 and 11). All mothers survived the event, but 6 (50%) of the fetuses died. A 1965 Reference reported a lightning strike of a woman in approximately the 11th week of gestation (1). The woman briefly lost consciousness, but other than transient nausea and anxiety that decreased as the pregnancy progressed, she was unhurt. She subsequently delivered a healthy term infant who was developing normally at 5 months of age. This report also described five other cases of lightning strikes of pregnant women that occurred between 18331959 with two fetal deaths. In one of the latter cases, the electrical injury caused uterine rupture in a mother at 6 months' gestation requiring an immediate cesarean section that was unable to save the fetus. Two cases of lightning strikes in term pregnant women were reported in 1972 (7). Both women were in labor when examined shortly after the events. One infant was delivered 12.5 hours after the maternal injury but died 15.5 hours after birth apparently secondary to congestive heart failure. In the other case, a healthy infant was delivered 14 hours after the lightning strike. A 1979 report described a near-fatal lightning strike in the chest of a 21-year-old woman at 34 weeks' gestation (8). Successful cardiopulmonary resuscitation was performed on the mother, but fetal heart tones were absent on initial examination. A stillborn fetus was delivered 48 hours after admission while the mother was still comatose. No fetal movements were felt by a 12-year-old mother at term after awakening from a lightning strike (9). She went into labor 9 days after the accident and delivered a macerated male fetus. Both the fetus and the placenta appeared grossly normal. A case of a woman in her 7th month of pregnancy who was struck in the right arm by lightning was published in 1982 (10). She apparently did not lose consciousness. Examination revealed minimal maternal injury and normal fetal heart tones. A healthy infant was delivered 10 weeks later who is developing normally at 19 months of age. Finally, the picture and brief description of a 41-year-old woman, in her 26th week of pregnancy, who was struck by lightning was presented in 1994 (11). The woman, but not the fetus, survived. Interestingly, the direction of the lightning strike in the mother was discussed in later correspondence (12,13).

Electroconvulsive therapy (ECT) for depression and psychosis in pregnant patients has been the subject of a large number of References (14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33, 34,35,36,37,38 and 39). The procedure has been used in all trimesters of pregnancy and is considered safe for the fetus. One report described mental retardation in a 32-month-old child whose mother had received 12 ECT treatments in the 2nd and 3rd trimesters for schizophrenia, but the investigators did not believe the treatments were responsible (37). A 1955 Reference examined 16 children who had been exposed in utero to maternal ECT between the 9th and 21st weeks of pregnancy (38). The age of the children at examination ranged from 14 to 81 months and all exhibited normal mental and physical development. Transient (2.5 minutes) fetal heart rate deceleration was observed in a twin pregnancy in which the mother was receiving ECT under general anesthesia (39). A total of eight ECT treatments were given, two before the observed deceleration and five afterwards.

General guidelines for electroconvulsive therapy established by the National Institutes of Health (NIH) were published in 1985 (34). The NIH report recommended that ECT, instead of drug therapy, be considered for pregnant patients with severe depression or psychosis in their 1st trimester but did not mention use in the other phases of gestation. Guidelines for the use of ECT in pregnant women were first proposed in 1978 (29) and then later expanded in 1984 (33). The combined guidelines from these two sources are: (a) thorough physical examination, including a pelvic examination, if not completed earlier; (b) the presence of an obstetrician; (c) endotracheal intubation; (d) low-voltage, nondominant ECT with EEG monitoring; (e) electrocardiographic monitoring of the mother; (f) evaluation of arterial blood gases during and immediately after ECT; (g) Doppler ultrasonography of fetal heart rate; (h) tocodynamometer recording of uterine tone; (i) administration of glycopyrrolate (see Glycopyrrolate) as the anticholinergic of choice during anesthesia; and (j) weekly nonstress tests.

Only one report has been located that described arterial blood gas analyses during ECT in a pregnant patient (28). As observed in previous studies, maternal blood pressure (average systolic blood pressure increase 10 mm Hg) and heart rate (average pulse increase 15 beats/minute) rose slightly immediately after the shock, but no maternal hypoxia was measured. A fetal arrhythmia lasting about 15 minutes occurred that was apparently unrelated to oxygen changes in the mother (28).

Transient maternal hypotension after ECT was described in a 1984 case report (32). The adverse effect was attributed to decreased intravascular volume. IV hydration preceded subsequent ECT treatments in the patient, and no further episodes of hypotension were observed.

A 1991 report noted mild, bright red vaginal bleeding and uterine contractions after each of seven weekly ECT treatments between 3036 weeks' gestation (35). A cesarean section, performed at 37 weeks' gestation because of bleeding, confirmed a diagnosis of abruptio placentae. The authors attributed the complication to the transient marked hypertension caused by the ECT. Only one other report, however, has described vaginal bleeding after ECT (26). Three women, all in the 8th or 9th month of pregnancy, complained either of severe recurrent abdominal pain (N=2) or vaginal bleeding (N=1) after ECT. Therapy was stopped in these cases, and normal infants were eventually delivered.

Antiarrhythmic, direct-current cardioversion is considered a safe procedure during gestation (40,41,42 and 43). Cardioversion has been used in the 2nd trimester in a woman with atrial fibrillation after mitral valvulotomy (40), in the 1st trimester in a patient with atrial flutter in 1:1 atrioventricular conduction (41), 7 times during three pregnancies in one patient for atrial tachycardia resistant to drug therapy (42), and twice in a single patient in two pregnancies for atrial fibrillation (43). No fetal harm was noted from the procedure in any of these cases. Two review articles on cardiac arrhythmias during pregnancy considered cardioversion (with energies of 1050 J [44]) to be safe and usually effective in this patient population (44,45).

A 1992 Reference described the effect from using a Taser (an electronic immobilization and defense weapon) on a pregnant woman at an estimated 810 weeks' gestation (46). The subject, in custody at the time because of drug abuse, was struck by one dart above the uterus and by a second dart in the left thigh, thereby establishing a current path through the uterus (46). Vaginal spotting began the next day and heavy vaginal bleeding began 7 days after the Taser incident. Uterine curettage performed 7 days later confirmed the presence of an incomplete spontaneous abortion.

In summary, exposure of the pregnant woman to electric current may produce dramatically different fetal outcomes depending on the source and type of current. Based on published reports previous to 1997, otherwise harmless maternal exposure to household alternating current was usually fatal to the fetus. In contrast, a 1997 prospective controlled cohort study cited above described live births in 94% of their cases (5). The difference between this latter report and the previous published experience is most likely caused by selective reporting of adverse outcomes, the level of voltage involved (i.e., 110 V vs. 220 V), and whether the current passed through the uterus. Although the new data should lessen a woman's concern for her fetus after electric shock, pregnant women who have experienced this type of injury, even when deemed to be minor, should be advised to consult their health care provider. Oligohydramnios, intrauterine growth retardation, and fetal death may be late effects of exposure to alternating current (4). Lightning strikes of any human are often fatal, but in those rare cases in which the victim is pregnant and survives, about half of the fetuses will also survive. Electroconvulsive therapy and direct-current cardioversion do not seem to pose a significant risk to the fetus. However, abruptio placentae has been observed in at least one and possibly two cases after ECT. Based on one report, the use of a Taser weapon on a pregnant woman may result in spontaneous abortion.

Breast Feeding Summary

No data are available.

References

  1. Rees WD. Pregnant woman struck by lightning. Br Med J 1965;1:1034.
  2. Peppler RD, Labranche FJ, Comeaux JJ. Intrauterine death of a fetus in a mother shocked by an electric current: a case report. J La State Med Soc 1972;124:378.
  3. Jaffe R, Fejgin M, Aderet NB. Fetal death in early pregnancy due to electric current. Acta Obstet Gynecol Scand 1986;65:283.
  4. Leiberman JR, Mazor M, Molcho J, Haiam E, Maor E, Insler V. Electrical accidents during pregnancy. Obstet Gynecol 1986;67:861-3.
  5. Einarson A, Bailey B, Inocencion G, Ormond K, Koren G. Accidental electric shock in pregnancy: a prospective cohort study. Am J Obstet Gynecol 1997;176:67881.
  6. Einarson A, Innocencion G, Koren G. Accidental electric shock in pregnancy: a prospective cohort study (abstract). Reprod Toxicol 1995;9:581.
  7. Chan Y-F, Sivasamboo R. Lightning accidents in pregnancy. J Obstet Gynaecol Br Commonw 1972;79:7612.
  8. Weinstein L. Lightning: a rare cause of intrauterine death with maternal survival. South Med J 1979;72:6323.
  9. Guha-Ray DK. Fetal death at term due to lightning. Am J Obstet Gynecol 1979;134:1035.
  10. Flannery DB, Wiles H. Follow-up of a survivor of intrauterine lightning exposure. Am J Obstet Gynecol 1982;142:2389.
  11. Zehender M. Images in Clinical Medicine: Struck by lightning. N Engl J Med 1994;330:1492.
  12. Bourke DL, Harrison CM, Sprung J. Direction of a lightning strike. N Engl J Med 1994;331:953.
  13. Zehender M, Wiesinger J. Direction of a lightning strike. N Engl J Med 1994;331:954.
  14. Goldstein HH, Weinberg J, Sankstone MI. Shock therapy in psychosis complicating pregnancy; a case report. Am J Psychiatry 1941;98:2012.
  15. Thorpe FT. Shock treatment in psychosis complicating pregnancy. Br Med J 1942;2:281.
  16. Polatin P, Hoch P. Electroshock therapy in pregnant mental patients. NY J Med 1945;45:15623.
  17. Sands DE. Electro-convulsion therapy in 301 patients in a general hospital. Br Med J 1946;2:28993.
  18. Gralnick A. Shock therapy in psychoses complicated by pregnancy; report of two cases. Am J Psychiatry 1946;102:7802.
  19. Turner CC, Wright LD. Shock therapy in psychoses during pregnancy; report of one case. Am J Psychiatry 1947;103:8346.
  20. Moore MT. Electrocerebral shock therapy; a reconsideration of former contraindications. Arch Neurol Psychiatry 1947;57:693711.
  21. Simon JL. Electric shock treatment in advanced pregnancy. J Nerv Ment Dis 1948;107:57980.
  22. Block S. Electric convulsive therapy during pregnancy. Am J Psychiatry 1948;104:579.
  23. Charatan FB, Oldham AJ. Electroconvulsive treatment in pregnancy. J Obstet Gynaecol Br Emp 1954;61:6657.
  24. Laird DM. Convulsive therapy in psychoses accompanying pregnancy. N Engl J Med 1955;252:9346.
  25. Smith S. The use of electroplexy (E.C.T.) in psychiatric syndromes complicating pregnancy. J Ment Sci 1956;102:796800.
  26. Sobel DE. Fetal damage due to ECT, insulin coma, chlorpromazine, or reserpine. Arch Gen Psychiatry 1960;2:60611.
  27. Impastato DJ, Gabriel AR, Lardaro HH. Electric and insulin shock therapy during pregnancy. Dis Nerv Syst 1964;25:5426.
  28. Levine R, Frost EAM. Arterial blood-gas analyses during electroconvulsive therapy in a parturient. Anesth Analg 1975;54:2035.
  29. Remick RA, Maurice WL. ECT in pregnancy. Am J Psychiatry 1978;135:7612.
  30. Fink M. Convulsive and drug therapies of depression. Annu Rev Med 1981;32:40512.
  31. Loke KH, Salleh R. Electroconvulsive therapy for the acutely psychotic pregnant patient: a review of 3 cases. Med J Malaysia 1983;38:1313.
  32. Repke JT, Berger NG. Electroconvulsive therapy in pregnancy. Obstet Gynecol 1984;63(Suppl):39S41S.
  33. Wise MG, Ward SC, Townsend-Parchman W, Gilstrap LC III, Hauth JC. Case report of ECT during high-risk pregnancy. Am J Psychiatry 1984;141:99101.
  34. Office of Medical Applications of Research, National Institutes of Health. Electroconvulsive therapy. JAMA 1985;254:21038.
  35. Sherer DM, D'Amico ML, Warshal DP, Stern RA, Grunert HF, Abramowicz JS. Recurrent mild abruptio placentae occurring immediately after repeated electroconvulsive therapy in pregnancy. Am J Obstet Gynecol 1991;165:6523.
  36. Yellowlees PM, Page T. Safe use of electroconvulsive therapy in pregnancy. Med J Aust 1990;153:67980.
  37. Yamamoto J, Hammes EM, Hammes EM Jr. Mental deficiency in a child whose mother was given electric convulsive therapy during gestation. A case report. Minn Med 1953;36:12601.
  38. Forssman H. Follow-up study of sixteen children whose mothers were given electric convulsive therapy during gestation. Acta Psychiatr Neurol Scand 1955;30:43741.
  39. Livingston JC, Johnstone WM Jr, Hadi HA. Electroconvulsive therapy in a twin pregnancy: a case report. Am J Perinatol 1994;11:1168.
  40. Vogel JHK, Pryor R, Blount SG Jr. Direct-current defibrillation during pregnancy. JAMA 1965;193:9701.
  41. Sussman HF, Duque D, Lesser ME. Atrial flutter with 1:1 A-V conduction; report of a case in a pregnant woman successfully treated with DC countershock. Dis Chest 1966;49:99103.
  42. Schroeder JS, Harrison DC. Repeated cardioversion during pregnancy; treatment of refractory paroxysmal atrial tachycardia during 3 successive pregnancies. Am J Cardiol 1971;27:4456.
  43. McKenna WJ, Harris L, Rowland E, Whitelaw A, Storey G, Holt D. Amiodarone therapy during pregnancy. Am J Cardiol 1983;51:12313.
  44. Brown CEL, Wendel GD. Cardiac arrhythmias during pregnancy. Clin Obstet Gynecol 1989;32:89102.
  45. Rotmensch HH, Rotmensch S, Elkayam U. Management of cardiac arrhythmias during pregnancy. Current concepts. Drugs 1987;33:62333.
  46. Mehl LE. Electrical injury from tasering and miscarriage. Acta Obstet Gynecol Scan 1992;71:11823.

blog comments powered by Disqus