Acta Obstet Gynecol Scand 61:129- 136, 1982
PAIN RELIEF IN LABOR BY TRANSCUTANEOUS ELECTRICAL
NERVE STIMULATION
Testing of a modified stimulation technique and evaluation of the neurological and biochemical condition
of the newborn infant
Peter Bundsen, Klas Ericson, Lars-Erik Peterson and Klara Thiringer
From the Department of Obstetrics and Gynecology, Ostra sjukhuset, University of Goteborg, the Department
of Applied Electronics, Chalmers University of Technology, and the Departments of Statistics and Pediatrics, University of Goteborg, Goteborg, Sweden
Abstract. In this prospective randomized study of pain
relief in labor, the effect of transcutaneous electrical nerve
stimulation (TNS) performed over both the low-back and
suprapubic region was evaluated and compared with a control group not receiving TNS. Both high frequency and
pulse train TNS were used. The study included 24 induced
labors. In the TNS group, conventional methods were added when needed, while in the control group only conventional methods were used. Assessment of low-back and
suprapubic pain was performed by the parturient each hour
during the first stage. In the TNS group most of the parturients reported minimal or moderate low-back pain
throughout labor, while parturients in the control group
reported an increased intensity of low-back pain as labor
progressed. The effect on suprapubic pain was insignificant
in both groups. Neither TNS nor nitrous oxide-oxygen mixture and pethidine could reduce this pain component.
Course of labor, uterine activity and fetal heart patterns
were similar in the two groups. The neonates were evaluated
with Apgar score, assays of blood samples from the umbilical vein including blood lactate, plasma hypoxanthine
and blood gas, and neurobehavioral assessment on two occasions. All newborn infants were in good condition and no
significant differences between the two groups could be
demonstrated.
Several studies concerning transcutaneous electrical
nerve stimulation (TNS) for pain relief during labor
have been published recently (2, 4, 6, 7, 17, 21, 24,
27, 29, 31). No adverse effects on the mother or newborn infant, as judged by the routinely used monitoring techniques, have been reported. However, the
lack of reported side effects on infants stems from
clinical evaluation of the fetus and neonate including
the use of Apgar score, while more elaborate methods
for the investigation of fetal and neonatal well-being
have not been used. In all the studies TNS was found
concluded that TNS had a good effect on the low-
back pain, whereas the suprapubic pain was not alleviated by this stimulation technique (7, 24, 27). The
finding that TNS had a specific effect on the lowback pain focused interest on pain location and the
effect of conventional analgesic methods used in the
first stage of labor. Two recent studies at this department demonstrated that few women experienced
good relief of both low-back and anterior pain when
pethidine and/or nitrous oxide-oxygen mixture were
used (7, 8).
T o improve the effect of TNS, we suggested that
stimulation should also be given over the lower abdomen in order to reduce anterior pain (7). Robson
(24) tested suprapubic stimulation in 2 patients. Both
derived great relief from this treatment. However, it
cannot be excluded that suprapubic stimulation with
conventional electrodes might induce irregularities in
the fetal heart rate during unfavorable conditions owing to high current density close to the fetal heart.
The current density due to suprapubic stimulation
was therefore analyzed and safety criteria proposed
(9, 11). A special apparatus fulfilling these criteria
was tested clinically and no side effects on the mother
or child were found (9).
The aim of this study was to evaluate the effect of
dorsal and suprapubic TNS at two different frequencies (cf. 12, 13) during labor and compare the effect
with conventional methods of pain relief. The study
also comprises an elaborate evaluation of the condition of the newborn infant, including biochemical
tests and detailed neurological examination.
PATIENTS AND METHODS
clinic during pregnancy. In order t o have as uniform an inActa Obstet Gynecol Scand 61 (1982)
130
P . Bundsen et al.
vestigation group as possible, only induced labors were included. This means that the whole labor, from the first uterine contraction to parturition, could be observed. Induction
was only performed if the parturient’s cervix was ripe, judged by the modified Bishop score (1). A senior obstetrician
assessed the state of the cervix and thereafter decided on induction of labor. The most common indication for induction was post-term pregnancy (TNS group 11, control group
6). The second most common indication was pre-eclampsia
(TNS group 2, control group 1). In addition, labor was induced because of suspected intrauterine growth retardation
in one parturient in each group and for psychosocial reasons
in one in each group. Only Swedish-speaking women with
the fetus in the vertex position were included.
Standardized verbal and written information concerning
the study and the available methods of pain relief was given
to the parturients by one of the authors (P. B.). Women
who were primarily biased for or against a certain method
of pain relief were not included in the study. With the patient’s consent, she was randomly assigned to either the
TNS group or the control group. The only requirement of
women assigned to the TNS group was that they had to test
the effect of TNS before being offered other methods of
pain relief. If a parturient had to be delivered by cesarean
section, she was omitted from the study.
Intrapartal monitoring and management. Labor was induced at term by primary amniotomy and supervised by electronic monitoring (Corometrics R). The fetal heart rate was
registered by means of a scalp electrode and the uterine activity by means of an open-end intrauterine catheter. The
uterine activity was quantified by calculating the Montevideo units (10) and also the area under the pressure curve.
Duplicate measurements were made and the mean values of
two consecutive 10-min periods were used. These calculations were done by one of the authors (L. P.), who was not
aware of which method of pain relief had been used or to
which group the patient belonged.
An oxytocin infusion was given about half an hour after
amniotomy unless regular uterine contractions were apparent. Two parturients in each group received no oxytocin.
The parturients were asked to avoid the dorsal position in
the first stage. In the second stage the semi-recumbent position was used.
TNS was given by one of the authors (P. B.) over the
painful area, i.e. the low-back and/or suprapubic region.
Two different stimulation frequencies were used: high frequency 50 Hz stimulation and pulse train TNS, i.e. brief
trains of stimuli with an internal frequency of 50 Hz and a
repetition rate of 5 Hz (cf. 12, 13). For both types of stimulation, the pulse amplitude was increased until the patient
experienced paraesthesia in the painful areas (30 - 40 mA).
These two stimulation techniques were used at random. If
the first stimulation technique did not have any effect or
caused discomfort, the other stimulation technique was tested after a trial period of 15 - 30 min. Thereafter conventional pain relief was given according to the womens’ wishes
and needs, provided there were no contra-indications.
A specially designed electrode (11) was taped over the
lower part of the abdomen just above the pubic region.
Conventional electrodes (Ceptor trodeR 2 x 35 cm2, Med.
General) were taped over the back paravertebrally and corActa Obstet Gynecol Scand 61 (1982)
responding to the dermatomes Th 10-L 1. The electrodes
were connected to a stimulator, specially built for this
study. The stimulator was current controlled and capable of
generating a maximum of 50 mA, 0.2 ms biphasic square
pulses over a maximum load of 3 000 ohms. The stimulator
was provided with sensing devices which interrupted the
current in the event of sudden changes in pulse length or
stimulation frequency. A filter was used in order to permit
good ECG recording (9).
The women assigned to the control group received conventional obstetric analgesia, according to their wishes and
needs. The methods used were: nitrous oxide-oxygen mixture, pethidine, diazepam, extradural analgesia (EDA),
paracervical block (PCB) and pudendal block.
Evaluation of analgesic effect. At one-hour intervals after
amniotomy the cervical dilatation was checked by the midwife and registered on the partogram and the cardiotocographic curve. At the same time, the women answered two
written questions concerning the intensity of low-back pain
and abdominal pain, according to a five-point scale -ranging from ‘no pain’ to ‘almost unbearable pain’. When the
contractions became painful, pain relief was given according to the conditions of this study. All obstetric analgesia
was registered, as were changes in the rate of oxytocin infusion. On the first day after delivery the women answered a
questionnaire concerning location and experience of pain in
different phases of labor and the effect of pain relief given.
Evaluation of the fetal and neonatal condition. The fetal
heart rate patterns were classified according to Hon (15) and
Hammacher et al. (14). The time from delivery, i.e. when
the whole baby was delivered, to first cry or breath was
noted. The Apgar scores at one and five minutes were recorded. At 60 sec the umbilical cord was double-clamped
and blood samples were drawn anaerobically from the vein
by one of us (P. B.). The sample for blood-gas analysis was
taken in a heparinized glass syringe and transported on ice
to the laboratory for immediate analysis. Oxygen saturation
(SO,) and hemoglobin concentration were measured using a
filter photometer (Radiometer OSM 2). Blood-gas tensions
and pH were measured at 38°C with a Radiometer BMS 3,
using standard electrodes. Base excess (BE) values were calculated from the Siggaard-Andersen nomogram at the prevailing hemoglobin concentration. Blood-lactate levels were
measured by an enzymatic method (Boehringer Mannheim).
Plasma hypoxanthine concentrations were determined using
a PO, electrode to measure the rate of oxygen consumption
after the addition of xanthine oxidase according to a method described by Saugstad (25).
The newborn infants were evaluated on two occasions by
the pediatrician participating in the study (K. T.) without
knowledge of the group to which the newborn infants belonged. The first examination was carried out in the delivery
room 30-120 min after parturition. Besides a detailed
physical examination, the evaluation of the infant included
state of alertness, reflexes, muscle tone and excitability. The
scoring also included the facial expression (drowsy, calm,
satisfied, alert, worried, irritable or disconsolate crying) and
the ability to follow a bright object (a yellow ball).
A more detailed neurological examination was performed
at the age of 10- 19 hours. This evaluation included 30
Pain relief in labor by TNS
Table I. Baseline variables.
Mothers
Age
Primiparae
Multiparae
TNS group
Control group
(n = 15)
(n = 9)
28k5
2624
3
6
5
10
Newborns
Gestational age
(completed weeks)
Birth weight (g)
Percentual weight loss
Apgar score
1 min
5 min
(%)
4121
3 6002460
6.521.7
41k1
3 620k370
7.022.1
9.5
10.0
9.6
9.9
items listed in the Appendix. The schedule is a modified
form of the neurological examination used by Prechtl &
Beintema (23). The examinations were carried out in calm
surroundings, about 2 hours after feeding.
Standard statistical methods were used to calculate means
and standard deviations. Student’s t-test was used to analyze the differences between arithmetical means.
RESULTS
Baseline variables. One parturient in each group was
delivered by cesarean section for reasons apparently
not related to pain relief given, and were excluded. Of
the remaining 26 parturients - 16 in the TNS group
and 10 in the control group - who entered the study,
one in each group received EDA owing to lack of effect of the other methods used. These 2 patients were
excluded due to the special problems associated with
parturients having EDA (8, 22, 26, 33).
Pain location was similar in the two groups. The
distribution between primiparae and multiparae was
equal (Table 1). In the newborn infants, gestational
age, birth weight, percentage weight loss and Apgar
scores were similar (Table I).
Table 11. Modified Bishop score and cervical dilata-
tion at amniotomy related to time course of labor.
Modified Bishop score
Cervical dilatation at
amniotomy (cm)
Onset of labor - 5 cm
dilatation (h)
5 - 10 cm dilatation (h)
10 cm - parturition (h)
Total duration of labor (h)
TNS group
Control group
6.321.6
7.621.5
2.1 k0.4
2.9k0.8
3.421.4
1.420.8
0.920.8
5.622.4
2.6k1.3
1.61- 1.2
l.lkl.l
5.3k2.6
13 1
Table 111. Uterine activity in different phases of the
first stage of labor (MeankSD). MU=Montevideo
units, A UC = area under the uterine pressure curve
f o r the same period.
Cervical
dilatation
Uterine
activity
TNS
Controls
3-4cm
MU
AUC
MU
AUC
MU
AUC
136k52
3.8k1.8
173k39
S.4k 1.3
207k41
5.72 1.S
11Sk38
3.621.1
137k-52
4.922.3
163k48
5.22 1.3
5-6cm
7-8cm
Course of labor. In Table I1 the modified Bishop
score, cervical dilatation at amniotomy and the duration of the different stages of labor are presented. Although the parturients in the control group had a
somewhat more favorable condition of the cervix and
a quicker dilatation to 5 cm, the time from 5 to 10 cm
and from 10 cm to parturition was somewhat shorter
in the TNS group, though showing no statistical significance. The interval from 5 cm to parturition was
2.3k1.5 hours in the TNS group compared with
2.7k2.3 hours in the control group. The mean values
for uterine activity as measured by both Montevideo
units and area below the pressure curve were somewhat higher in the TNS group than in the control
group (Table III), but the differences showed no statistical significance.
One post-term primipara in each group was delivered by vacuum extraction. The other parturients gave
birth spontaneously - one multipara in the control
group with the fetus in occipito-posterior position
and the remainder with fetuses in the occipito-anterior position.
Fetal condition during labor. The fetal heart rate patterns were analyzed visually with respect to basal
heart rate, deceleration patterns and long-term variability. No attempt to analyze short-term variability
was made. The analysis showed no differences between the groups concerning basal heart rate and de-.
celerations, and no specific effect due to TNS treatment could be discerned. The interpretation of longterm variability was complicated by the fact that
many parturients in both groups received pethidine.
However, in 2 patients receiving pulse-train TNS and
in one patient with high-frequency TNS, a reduced
long-term variability was apparent both before and
during the TNS treatment.
Acta Obstet Gynecol Scand 61 (1982)
132
P. Bundsen et al.
TNS GROUP
Suorapubic
Low - back
TNS (15)
Arnniofomy
crn 2 1
Pethidine
(13)
(12)
3 4
+
crn 2 1
TNS
4 2
+
.1
+
45
+
N2 0 / 0 2
(9)
5 3
, +
+2
.3
*2
*3
CONTROL GROUP
Arnniotomy
cm 2 9
t
cm 2 9
N 2 0 / 0 2 Pethidine
(9)
(8)
41
+
44
+
+I
Fig. 1. lnstigation of different analgesic methods in relation
to cervical dilatation at amniotomy.
Pain relieh first stage. The majority of parturients in
the TNS group were given TNS over the low-back region before suprapubic TNS was started, in accordance with the appearance of pain (Fig. 1). From amniotomy the cervix dilated on average 1.3 cm before
low-back TNS (15 cases) was given and 2.1 cm before
suprapubic TNS (13 cases) was given. In the TNS
group pethidine (12 cases) was given when cervix had
dilated on average 2.4 cm from amniotomy and
N 20/02
(9 cases) when cervix had dilated o n average
3.2 cm from amniotomy. One multipara in the TNS
group received PCB at a cervical dilatation of 6 cm.
She wanted low-back and suprapubic stimulation to
be continued after being given the blockade.
In the control group the cervix dilated on average
1.2 cm from amniotomy before N 2 0 / 0 2 was given (9
cases) and on average 1.5 cm before pethidine was
given (8 cases). One multipara in the control group
received PCB at a cervical dilatation of 4 cm.
Intrapartal assessment of low-back and suprapubic
pain was performed each hour during the first stage.
In 9 parturients in the TNS group and in 4 in the control group the cervix dilated from 5 to 10 cm within 1
hour, which resulted in few answers in the late first
stage (Table IV). Six parturients were randomized to
start with pulse-train TNS and 3 of these experienced
good relief of low-back pain, while one more parturient experienced good relief after changing from
pulse-train t o high-frequency TNS. Nine parturients
started with high frequency TNS. Among these, 5 experienced good relief of low-back pain and thereafter
one more parturient after changing to pulse-train
TNS. Twelve patients in the TNS group experienced
minimal or moderate low-back pain at a cervical dilatation of 4 - 5 cm. Seven of them reported unchanged
or reduced pain at 6- 10 cm, while 5 had no time to
answer due to rapid cervical dilatation. In the control
group 4 patients had minimal or moderate pain at
4 - 5 cm and all reported severe to almost unbearable
pain the the late first stage (Table IV). The majority
of parturients in both the TNS and control group experienced severe suprapubic pain at the time when
pethidine was given. The suprapubic pain was not affected by either TNS or N 2 0 / 0 2 and/or pethidine.
Pain relief, second stage. Pudendal block was given
to 13 parturients in the TNS group and 7 in the control group. Eight parturients in the TNS group and
none in the control group experienced good relief of
pain in the second stage. Five parturients in the TNS
group graded their total pain as only minimal or moderate in the second stage, compared with none in the
control group. This supports the observation that
TNS reduces pain also in the second stage.
Evaluation of the infants. All newborns were delivered in good condition and clinical signs of extrauterine
asphyxia were not present in any infant. The time
from delivery to first cry or breath did not exceed 30
sec in any case and Apgar scores (Table I) were similar in both groups. The mean values for umbilical
vein p H , blood gases, oxygen saturation, lactate and
Table IV. Location and intensity of pain in relation to cervical dilatation.
> 5 cm
5 5 cm
Minimal or moderate low-back pain
Severe to almost unbearable low-back pain
Fully dilated within one hour
Minimal or moderate suprapubic pain
Severe to almost unbearable suprapubic pain
Fully dilated within one hour
Acta Obster Gynecol Scand 61 (1982)
TNS
Control
TNS
Control
12
3
4
5
1
5
3
5
2
7
7
1
7
1
7
7
10
1
5
3
Pain relief in labor by TNS
Table V. Blood samples taken from the doubleclamped um bilical vein (Mean +- SO).
TNS group
Control group
7.3520.06
4.6t0.9
5.0k0.7
63k.13
6.0k3
2.7k0.9
6.3k6.5
7.36k0.08
4.1 k0.6
5.7e0.5
67k13
7.2k3.5
3.0k1.9
2.4k3.6
~
PH
Pco2
P o 2 (kPa)
so,
(70)
BD (mmol/l)
Lactate (mmol/l)
Hypoxanthine (pmol/l)
133
strated in 9 and 11 respectively of the 13 infants examined in the TNS group, while in the control group
4 of the 8 infants studied were given optimum scores.
The newborn infants in the TNS group achieved 22.6
optimum items, compared with 21.6 in the control
group.
DISCUSSION
hypoxanthine are given in Table V . The mean values
showed no deviations from values usually found after
normal births (18), and were similar in the TNS and
control group. Although the hypoxanthine levels in
the TNS infants were more widely scattered, with a
greater range (0- 16.8 pmol/l) than in the control
group (0 - 9.8 pmol/l), the difference was not significant when tested by the Wilcoxon rank-sum test.
The scores attained in the neurological examinations of the infants are summarized in Table VI. The
examinations did not reveal any disturbances attributable to TNS. The mean scores and score ranges
were comparable for the two groups of infants. In the
more detailed second examination the infants demonstrated no major neurological deviations apart from
one infant in each group with evident irritability. This
was attributed to the fact that they were delivered by
vacuum extraction. No significant differences could
be found in muscular tone, excitability, number of
optimum items or total neurological score, though
there was a slight tendency towards more normal
values for all variables in the TNS group. Optimum
excitability and tone scores (14 1) could be demon-
+
In this study a modified technique for TNS for pain
relief during labor was tested. A specially designed
current-controlled stimulator was used. It was possible to test both pulse train and high-frequency TNS
and to stimulate suprapubically with an electrode fulfilling the safety criteria proposed in an earlier study
(9).
Only induced labors were included. Although the
modified Bishop score and the degree of cervical dilatation at amniotomy were lower in the TNS group
than in the control group, no significant differences
were noted in the time course of labor. Rather, there
was a slight tendency in the TNS group toward increased uterine activity, as measured in Montevideo
Units and area below the pressure curve. This is in
agreement with Kubista et al. (17), who concluded in
their study that apart from the good analgesic effect
obtained, an advantage of TNS was the quick course
of labor.
The analysis of the fetal heart rate patterns disclosed no significant differences. The interpretation of
long-term variability was, however, complicated by
the fact that many parturients in both groups received
pethidine.
The previously documented good effect of TNS on
low-back pain (7) was confirmed in this study. This
pain-reducing effect of TNS was maintained through-
Table V1. Examination of the newborns.
TNS
(n = 14)
Controls
(n = 8)
9.3k1.5
6.5-11
7
8.6k2.1
5-11
4
13.9tl.l
11
15.4k2.0
4
14.7k1.3
9
22.6k2.3
14.8k2.4
4
21.6k4.5
First examination (max 11)
Range
Infants with score
2
10
Second examination
Tonus score (optimal = 14,
range 8 - 30)
Infants with score 14k1
Excitability score
(optimal = 14, range 9 - 33)
Infants with score 1421
Total number of optimal items (max 27)
Acta Obstet Gynecol Scand 61 (1982)
134
P . Bundsen et al.
out labor. The parturients did not report any alterations in pain intensity of the low-back pain during the
first stage. Although pudendal block was used equally often in both groups, while nitrous oxide-oxygen
mixture was used less often in the TNS group than in
the control group, relief of pain was better and pain
intensity lower in the TNS group in the second stage.
It is suggested that the high incidence of good pain
relief is due to the TNS treatment. The study indicated that parturients who failed to experience
relief of low-back pain with high-frequency TNS
could be helped by pulse-train TNS, and vice versa.
This is in keeping with studies performed during
other conditions (12, 13, 20).
In the first stage no obvious effect on suprapubic
pain was observed in either TNS or control group.
Thus, neither TNS nor N 2 0 / 0 2 and/or pethidine
could reduce this pain component. A question that
arises is whether the suprapubic pain in the first stage
is resistant to TNS. This question cannot be answered
on the basis of experience from this study. The
suprapubic pain is undoubtedly more intense and well
defined than the diffuse low-back pain. This indicates
indirectly that the suprapubic pain is mediated mainly
via A delta fibres, while the low-back pain is mediated via C fibres. Experience from TNS treatment in
other conditions indicates that the best effect is usually obtained in C-fibre-mediated pain (3). It should be
pointed out that the suprapubic electrode was designed to give high current density in the vicinity of the
electrode, while deeper structures would receive
minimal current.
Experience from TNS treatment in other painful
conditions indicates that optimal pain relief is obtained when both skin and muscle afferents are activated
(3). During pulse-train TNS, activation of muscle afferents seems to be of major importance (28). It is
therefore possible that the pain-reducing effect of
suprapubic TNS can be enhanced if stimulation is
also allowed to activate muscle afferents. Further
safety studies will probably show that the proposed
preliminary current density standard for the fetal
heart (9) is too low and can be raised without jeopardizing safety.
Since it cannot be excluded that suprapubic stimulation might induce irregularities in the fetal heart
rate in unfavorable cases, the need for meticulous
fetal monitoring and thorough evaluation of the
newborn infant is obvious in a study of this kind. We
are not aware of any reports concerning the condition
of the newborn infant after TNS in labor as assessed
Acta Obstet Gynecol Scand 61 (1982)
by methods other than the Apgar score. Recent
studies on newborn infants have indicated that neurobehavioral evaluation gives more adequate information on neonatal condition than does the routinely used Apgar score (18, 22, 26).
No infant in this study developed extrauterine asphyxia, as measured by Apgar score. The mean umbilical vein pH was similar in the two groups and did
not differ from values usually found after normal deliveries (16) or after induced labor (18). Mean values
for p C 0 2 , PO 2 , SO 2 and BE were also in accordance
with normal values found in umbilical blood and no
significant differences were noted between the TNS
and control group. All infants except one baby in the
control group had lactate values below 4 mmol/l.
Hypoxanthine is a degradation product of energyrich cell purines (ATP and ADP) and has recently
been claimed to reflect tissue hypoxia in a specific and
sensitive way (25). During graded asphyxia in the fetal lamb the concentration of hypoxanthine in fetal
plasma showed a close correlation to other indices of
hypoxia (32). Only a few small clinical materials of
newborns have so far been published on this topic
(19, 25, 30). In infants with pH values above 7.18
Lipp et al. found values between 6 and 28 pmol/l,
while Saugstad measured values between 11 and 61.5
pmol/I in association with signs of perinatal asphyxia.
In another group of neonates with Apgar scores exceeding 7, a value of 12.2+7.2 was measured in
arterial plasma at an age of 10 min (30). Our values
are of the same magnitude as these measurements and
confirm, additionally, the absence of perinatal
asphyxia.
The neurological examinations of the infants born
after TNS and after conventionally used pain relief
also failed to demonstrate any significant differences
between the groups. The neurological scores achieved
by the infants at the second examination are close to
the scores Leijon et al. found after induced deliveries
and normal births when they used the same scoring
system (18). Our infants scored somewhat lower for
optimum items, which we believe to be due to interobserver difference. The tendency towards slightly
more frequent ‘normal’ and ‘optimum’ scoring in the
TNS group might be the result of the less frequent use
of the nitrous oxide-oxygen mixture in this group.
It can thus be concluded that no adverse effect of
TNS is demonstrable by clinical, laboratory or neurological examination of the infants after pain relief by
TNS .
Pain relief in labor by TNS
APPENDIX
Grouping of items in the neurological examination,
Figures in parenthesis are possible scores
Items measuring muscular tonus (8-30)
Spontaneous posture supine position (1 -3)
Resistance against passive movements, body and neck (1 -4)
Resistance against passive movements, arms (1 -4)
Resistance against passive movements, legs (1 -4)
Recoil, arms (1 - 4)
Traction response, arms (1 -4)
Traction response, head (1 -4)
Head control, vertical position (1 -3)
Items measuring excitability (9- 33)
Optical blink reflex (1 - 3)
Acoustic blink reflex (1 - 3)
Patellar reflex (1 -4)
Palmar grasp (1 - 4)
Withdrawal reflex (1 - 4)
Rooting reflex (1-4)
Ability to suck (1-4)
Moro tremor (1 - 3)
Spontaneous motility (1 -4)
Optimal items (items where optimal response is possible
to state)
The items measuring muscular tonus (see above)
The items measuring excitability (see above
Moro tremor excluded)
Face expression (1 - 2 )
Cry (1 -4)
Symmetry in body position (1 - 2 )
Eyes following a yellow ball ( 1 - 3 )
Doll’s eye test ( I - 2)
Pupil’s reaction to light (1 - 3)
Glabellar reflex (1 - 2 )
Moro reflex (1 - 4)
Crawling ( 1 - 4)
Placing response (1 - 2 )
Automatic walking (1 - 3)
ACKNOWLEDGEMENTS
The analyses of the fetal heart rate patterns were performed
by Ass. Prof. Ingemar Ingemarsson, Department of Obstetrics and Gynecology, University of Lund, Sweden. The
study was financially supported by the Swedish Medical Research Council (grant no. K79-17P-5554-01G), Allmanna
BB:s Minnesfond and the National Swedish Board for
Technical Development.
REFERENCES
I . Anderson, A. B. M. & Turnbull, A. C.: Relationship
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Submiited for publication April 29, I980
Peter Bundsen, M.D.
Department of Obstetrics and Gynecology
Ostra sjukhuset
S - 416 85 Gothenburg
Sweden