Hindawi Publishing Corporation
Journal of Pregnancy
Volume 2015, Article ID 483195, 7 pages
http://dx.doi.org/10.1155/2015/483195

Research Article
Naegele Forceps Delivery and Association between
Morbidity and the Number of Forceps Traction Applications:
A Retrospective Study
Naoki Matsumoto, Toshifumi Takenaka, Nobuyuki Ikeda, Satoshi Yazaki, and Yuichi Sato
Department of Obstetrics and Gynecology, Tatedebari Sato Hospital, 96 Wakamatsucho, Takasaki, Gunma 370-0836, Japan
Correspondence should be addressed to Naoki Matsumoto; research@matsumotoc.org
Received 4 April 2015; Revised 20 August 2015; Accepted 23 August 2015
Academic Editor: Fabio Facchinetti
Copyright © 2015 Naoki Matsumoto et al. This is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited.
Objective. To present the method of Naegele forceps delivery clinically practiced by the lead author, its success rate, and morbidity
and to evaluate the relationship between morbidity and the number of forceps traction applications. Methods. Naegele forceps
delivery was performed when the fetal head reached station +2 cm, the forceps were applied in the maternal pelvic application,and traction was slowly and gently performed. In the past two years, Naegele forceps delivery was attempted by the lead author
in 87 cases, which were retrospectively reviewed. Results. The numbers of traction applications were one in 64.7% of cases, two in
24.7%, and three or more in 10.7%. The success rate was 100%. No severe morbidity was observed in mothers or neonates. Neonatal
facial injury occurred most commonly in cases with fetal head malrotation, elevated numbers of traction applications, and maternal
complications. Umbilical artery acidemia most commonly occurred in cases with nonreassuring fetal status. The significant crude
odds ratio for three or more traction applications was 20 in cases with malrotation. Conclusion. Naegele forceps delivery has a highsuccess rate, but multiple traction applications will sometimes be required, particularly in cases with malrotation. Malrotation andelevated numbers of traction applications may lead to neonatal head damage.

1. Introduction
Recently, the very high rate of cesarean delivery has been a
topic of discussion and is considered a problem that should
be solved [1]. In 2011, the cesarean delivery rate was 33% of
all births in the United States [2]. With the increasing rateof cesarean delivery, the rate of operative vaginal deliveries
has decreased during the past 20 years [2]. In Japan, theoverall rate of cesarean delivery in 2011 was 19% [3] and that at
high-level medical facilities was 34% [4]. In operative vaginal
delivery, the rate of forceps delivery has decreased more thanthat of vacuum extraction [5]. In Japanese high-level medical
facilities, the rates of cesarean, vacuum, and forceps delivery
are 20%, 6%, and 1%, respectively, among all deliveries except
for planned cesarean deliveries [4].
Thus, forceps delivery has become a minor obstetricalmethod in management of labor and delivery. However,the lead author considers that forceps delivery is his firstchoice method in the operative vaginal deliveries. Forceps
delivery has a higher success rate than vacuum extraction[6] and affords robust reliability for an experienced operator.
Nonetheless, the author always bears in mind the potential
risks of forceps. Therefore, he applies the forceps sufficiently
in a gentle and slow manner to avoid undue maternal andneonatal morbidity. Sometimes multiple traction applications
are needed. Some obstetricians believe that forceps delivery
should be completed by one forceps’ traction application[7]. However, no recent study has assessed the correlation
between morbidity and the number of forceps traction
applications.
The aim of this study was to present the method ofNaegele forceps delivery clinically practiced by the leadauthor and its success rate and morbidity and moreover to2evaluate the relationship between morbidity and other factors
including the number of forceps traction applications.

2. Methods
2.1. Delivery Procedures with Naegele Forceps. Naegele forceps
are most commonly used for forceps delivery in Japan. They
have adequate pelvic and cephalic curves for nonrotational
forceps delivery and fenestrated blades that permit firmer
grasp of the fetal head [5]. Furthermore, Japanese obstetricians commonly use Naegele forceps modified and ameliorated for the Japanese women, which are called UTokyo
Naegele forceps. They have lighter weight (417 g), shorter
length (35 cm), and thinner blades than the original. Indications, prerequisites, and precautions for forceps delivery thatwere stipulated in the guidelines for obstetrical practice inJapan [8] were followed. In principle, forceps delivery was
performed when the leading point of the fetal head reachedor nearly reached station +2 cm over the ischial spine. The
measurement of the station was performed based on internal
digital examination in the dorsal position. The station wasdetermined as the distance on the pelvic axis from the ischialspine to the leading point of the fetal head. Before applicationof forceps delivery, fetal head rotation and spine position werechecked by internal digital examination as well as abdominal(sometimes with transperineal) ultrasonography. Based on
this assessment, fetal head malrotation was diagnosed andclassified as the occiput transverse position (with rotation
greater than 45 degrees) or occiput posterior position. On
the decision of forceps delivery, verbal informed consent was
obtained. The option of primary cesarean delivery without
trial of operative vaginal delivery was presented to the patient
especially when the forceps trial was considered to have a
possibility of failure and relatively high risk of maternal andneonatal morbidity. Rotation with Kielland rotational forceps
was attempted when it was considered that it might effectively
improve malrotation. In this study, it was attempted in threecases. Effective improvement of malrotation was obtainedin one case, which was excluded from this study, but notin the other two cases, which were followed by Naegele
forceps delivery and were included in this study. Naegele
forceps were applied in the maternal pelvic application. Afterarticulation of the forceps, the operator (the lead author)
suspended the hooks on the first and middle fingers andplaced the handles on the palm of his right hand with anunderhand grip. He did not usually hold the handles. To
feel the exact progression and to avoid sudden emergence,
the tips of the fingers of the left hand were placed on the
fetal head. To avoid falling, he adopted a fighter’s stancewith a wide stance and slightly bent knees. Before genuine
traction, test traction was applied to check the forceps grip,
fetal head movement, and feeling of fetal descent. Except inurgent situations, forceps traction was applied slowly andgently in synchrony with contractions and pushing efforts
to avoid undue maternal and neonatal damage and forceps
slipoff. Traction was directed, as per principle, along the axisof the birth canal with no rotational movement. Episiotomy(midline or mediolateral) was performed if necessary. The
forceps were disarticulated when the operator considered

Journal of Pregnancy
Pregnant women whose labors weremanaged chiefly by the lead authorn = 288
64%
Normal vaginal deliveryn = 185
Primary
5% emergency
cesareann = 14

Operative deliveryn = 103
Forceps31%
n = 88

Vacuumextraction 0.3%
n=1Completed
n=1

Trial of Kielland
rotational forceps
n=3
Completed
n=1

Incomplete
n=2Naegele forceps
n = 87
Completedn = 87

Figure 1: Mode of delivery of 288 term pregnant women with live
singleton pregnancies and cephalic presentation whose labor anddelivery were managed chiefly by the lead author.

the fetal head would not recede. The operator dictated a
midwife to support the delivery by perineal protection whenrequired. Forceps application was halted when the operator
felt no evidence of progressive descent with three traction
applications at most.
2.2. Study Design. The study period was the past two years
from July 2012 to June 2014. In this period, 288 term
pregnant women with live singleton pregnancies and cephalicpresentation were managed chiefly by the lead author. In
87 of these cases, Naegele forceps delivery was attemptedand successfully completed (Figure 1). We retrospectively
reviewed the 87 cases and obtained patient characteristic
factors, parturition outcomes, and short-term (during aperiod of one month after delivery) maternal and neonatal
morbidity outcomes from the medical records.
The relationships between characteristic factors and morbidity were assessed by Fisher’s exact test. The five morbidity
outcomes considered were as follows: maternal anal sphincter
injuries, acute postpartum urinary retention lasting over
24 h, dehiscence or maternal injuries except for perineal
lacerations, neonatal facial injuries, and umbilical arteryacidemia. Anal sphincter injuries were defined as third- or
fourth-degree perineal lacerations. Acute postpartum urinary retention was defined as a postvoid residual volumeof >100 mL. Neonatal facial injuries were defined as forceps
marks with bruising or skin lacerations. Umbilical arteryacidemia was defined as acidemia with umbilical artery pH<7.2. The relationship between characteristic factors and thenumber of traction applications was assessed by calculation of
crude odds ratios for two or more and three or more traction
applications.
The study protocol was approved by the ethical review
board of the hospital. Two-tailed 𝑃 values and confidence
intervals were calculated using univariate methods including

Journal of Pregnancy
Fisher’s exact test and univariate logistic regression. 𝑃 valuesof <0.05 were considered statistically significant.

3. Results
The characteristics of 87 patients on whom Naegele forceps
delivery was performed are presented in Table 1. The proportion of nulliparas in the study group (82.8%) was larger
than that in the normal vaginal delivery group (35.1%) in
the same period. Maternal complications included gestational
diabetes mellitus (11.5%), pregnancy-induced hypertension(10.3%), and psychiatric disorders (4.6%). One case with aprevious cesarean history was managed for a trial of labor
after cesarean. Fetal head malrotation was diagnosed in 14(16.1%) cases before forceps delivery, including seven cases
each of occiput transverse and occiput posterior position.
The numbers of forceps traction applications were one in
64.7% of cases, two in 24.7%, and three or more in 10.7%. The
maximum number of traction applications was six. Uterine
fundal pressure maneuvers were required only in two (2.3%)
cases. The median and maximum traction-to-delivery times
were 2 min and 13 min, respectively.
No forceps failure and no slipoff were experienced in
the study period, so that the success rate was 100%. No
case of shoulder dystocia occurred. Morbidity associatedwith the forceps deliveries is presented in Table 2. No severe
morbidity was seen in the mothers or neonates during shortterm observation. Maternal anal sphincter injuries occurredin 35.6%. All cases of anal sphincter injury were appropriately
examined and repaired using absorbable sutures without
leading to severe problems. Acute postpartum urinary retention lasting over 24 h was seen in 13.8% of cases. All of thesecases were eventually resolved by passive catheter bladderdrainage. Eight (66.7%) of these cases were resolved within
48 h after delivery. The longest duration to resolution ofurinary retention was eight days after delivery. Dehiscenceand maternal injuries except for perineal lacerations wereseen in five cases (5.7%). They included two cases of pudendal
hematoma, two cases of pubic symphysis pain, and one caseof wound abscess, which were all resolved in a short period.
Neonatal facial injuries were seen in 18.4% of cases. All weremild, and no treatment was indicated. Concerning umbilicalartery acidemia, no severe acidemia and no severe neonatal
asphyxia were seen. Apgar scores (at 1 and/or 5 min) lower
than 7 were not observed.
The relationships between patient characteristic factors
and morbidity are described in Table 3. No significant relationship was observed between any of these factors andmaternal morbidity. Neonatal facial injury occurred mostcommonly in cases with malrotation, elevated numbers oftraction applications, and maternal complications. Umbilicalartery acidemia occurred most commonly in cases with chief
indication of nonreassuring fetal status.
Figure 2 shows the crude odds ratios for two or more andthree or more traction applications. Significant odds ratios
for two or more traction applications were 5.5, 3.3, and 2.9
in cases with malrotation, augmentation, and station of ≤+2,
respectively. Significant odds ratios for three or more traction
applications were 20 in cases with malrotation.

3
Table 1: Characteristics of the 87 pregnant women on whom
Naegele forceps delivery was performed.
MedianRange
Factors
Gestational age at delivery
39 5/7 37 3/7–41 4/7(weeks)
Early term (37 0/7-38 6/7
weeks)
Full term (39 0/7-40 6/7
weeks)
Late term (41 0/7 weeks andafter)32
19–40
Age (years)
ParityNullipara
Para 1
Para 2
Maternal complications
158
147–170
Maternal height (cm)59.6
44.7–91.8
Maternal weight at labor (kg)Maternal BMI at labor
24.2
18.6–34.8(kg/m2 )3036
2072–3926
Neonatal birth weight (g)Augmentation
Epidural analgesia
Episiotomy
MidlineMediolateral
Fetal head malrotation
Chief indication
Prolonged second stage
Nonreassuring fetal status
Severe PIH
Station (cm)
+1
+2
+3
≥+4
Missing
Numbers of forceps traction
applications
1
2
3
4
5
6
Missing
Uterine fundal pressure
maneuverTraction-to-delivery intervals
2
0–13
(min)

n

%

19

21.8

56 64.4
12

13.8

72
11
4
37

82.8
12.6
4.6
42.5

48 55.2
18 20.7
35 40.2
24 27.6
11 12.6
14 16.1
51
33
3

58.6
37.9
3.4

2 2.4
41 47.7
30 34.9
13 15.1
1

55 64.7
21 24.7
5 5.9
2 2.4
1
1.2
1
1.2
2
2

2.3

BMI: body mass index; PIH: pregnancy-induced hypertension.

4. Discussion
All cases were successfully delivered by the Naegele forceps
delivery according to the lead author’s method as mentioned

4

Journal of Pregnancy
Table 2: Morbidity associated with Naegele forceps deliveries.

Morbidity
Maternal morbidity
Postpartum hemorrhage >500 mL
Blood transfusion
Perineal laceration
None
1st degree
2nd degree
3rd degree
4th degree
Acute postpartum urinary retention lastingover 24 h
Dehiscence and maternal injury except for
perineal lacerations
Neonatal morbidity
Facial injuries
Cephalohematoma
Umbilical artery acidemia
Umbilical artery pH: 7.10–7.19
Umbilical artery pH: <7.1
Neonatal intensive care unit admission

n

%

5
1

5.7
1.1

0
2
54
26
5

0.0
2.3
62.1
29.9
5.7

12

13.8

5

5.7

16
3

18.4
3.4

8
0
1

9.2
0.0
1.1

in the Methods. The forceps delivery was completed with one
forceps’ traction application in approximately two-thirds ofthe cases, within two in nearly 90%, and within three in 95%.
Malrotation is associated with traction applied three times ormore. Malrotation and elevated numbers of forceps traction
applications were both related to the occurrence of neonatal
facial injury. No severe morbidity was seen in mothers andneonates in the short-term observation.
All the cases were successfully delivered and no forceps
failure or slipoff was seen. The success rate of operative
vaginal delivery will vary with the chosen type of instrument.
In a meta-analysis, O’Mahony et al. [6] reported that forceps
delivery was less likely (with risk ratio 0.65) to fail to achievea vaginal delivery with the chosen instrument than vacuum
extraction. In a large-scale retrospective cohort study, BenHaroush et al. [9] reported that the failure rates of forceps
and vacuum extraction were 1.3% and 10.0%, respectively.
Even in cases with failed vacuum extraction, the failure rateof subsequent forceps was 3.5%. Generally, forceps delivery
is considered to have a higher success rate than vacuum
extraction [6, 10–13]. However, the success rates of operative
vaginal delivery will vary with other factors including range
of indication, approval for subsequent forceps after failed vacuum extraction, and the operator’s proficiency and preference[14].
In this study, forceps delivery was completed with one
traction application in approximately two-thirds of cases,
within two in nearly 90%, and within three in 95%. In atrial with vacuum extraction, excessive numbers of pulls
are considered to increase the risk of neonatal morbidity[10–13]. The guidelines for obstetrical practice in Japan [8]recommend five or fewer pulls in vacuum extraction. In
contrast, excessive numbers of forceps traction applications
are rarely discussed. There are no recent studies and norecommendations concerning the allowable maximum number of forceps traction applications. Not only in vacuum
extraction but also in forceps delivery, multiple traction
applications will sometimes be required in cases of dystocia,
particularly with fetal head malrotation. In the present study,
malrotation seems to be the strongest predictive factor toelevate the number of forceps traction applications. Fetal
head malrotation and elevated numbers of forceps traction
applications are both risk factors for neonatal facial injury.
In the present study, the neonatal facial injuries were mild;
therefore, our results may be insufficient to discuss the association between forceps delivery and severe neonatal injuries.
However, we believe that our results imply a potential risk
for severe neonatal head damage in cases with malrotation
and/or elevated numbers of traction applications. Carefulattention to the risk factors is thus required.
The rate of maternal anal sphincter injury in forceps deliveries is considered to be approximately 30% [11]. However,
the rate will vary with facility and practitioner. Hirsch etal. [15] reported historically two anal sphincter injury rates
in their level III teaching hospital. After they promulgateda recommendation to reduce the occurrence of high-degree
perineal laceration, the rate of anal sphincter injury with
operative vaginal delivery declined from 41% to 26% and thatwith forceps declined from 40% to 28%. The present leadauthor usually performs forceps delivery with priority given
to delayed disarticulation for smooth fetal head expulsion
and midline episiotomy for reducing postsuture pain when
episiotomy is needed. There may still be room for measures
to reduce the occurrence of anal sphincter injury. Operative
vaginal delivery is associated with the occurrence of postpartum urinary retention [16]. Symptoms are brief and are
typically resolved within 24 to 48 h of passive catheter bladderdrainage [5].
In their large-scale retrospective cohort study, Werner
et al. [17] reported that forceps delivery had a lower riskof adverse neonatal outcomes including cephalohematoma,
low Apgar score, and neurologic complications and posed ahigher risk of facial nerve palsy than did vacuum extraction.
In their meta-analysis, O’Mahony et al. [6] reported that facial
injury was more likely with forceps but cephalohematoma
was more likely with vacuum. Sequential use of vacuum andforceps is associated with increased risk of both maternal andneonatal injury [18]. Relatively low neonatal morbidity andhigh success rate are the chief reasons for the lead author’s
choice of forceps for the first-choice instrument.
The management of cases with occiput transverse position is clinically indeterminate. Recently, some researchers
have reevaluated the value of Kielland rotational forceps
delivery for fetal head malrotation [19, 20]. The lead author
uses the method only for cases with deep occiput transverse
position, which presents a relatively wide gap within the birthcanal to accommodate insertion of the blades of the Kielland
forceps and its rotational maneuvering. In cases of dystocia,
particularly with malrotation, nonrotational forceps delivery
poses a risk of rare and sometimes severe outcomes such

Journal of Pregnancy

5

Table 3: Relationship between patient characteristics and morbidity.

Factors

Acute postpartum
Maternal anal
urinary retention
sphincter injury
lasting over 24 h
(n = 31)(n = 12)%
Gestational age at delivery
Early term (37 0/7-38 6/7 weeks)
35.7
Full term (39 0/7-40 6/7 weeks)
31.6
Late term (41 0/7 weeks and after)
41.7
Maternal age≥35 years
48.0<35 years
30.7
ParityNullipara
37.5
Multipara
26.7
Maternal complications
Yes
27.0
No
42.0
Maternal height<155 cm
36.0≥155 cm
35.5
Maternal BMI at labor≥29 kg/m2
50.0<29 kg/m2
34.6
Neonatal birth weight≥3500 g35.7
<3500 g35.6
Augmentation
Yes
43.8
No
25.6
Epidural analgesia
Yes
38.9
No
34.8
Episiotomy
Yes
40.0
No
32.7
Fetal head malrotation
Yes
42.9
No
34.3
Station≤+2 cm27.9>+2 cm41.9
Chief indication
Prolonged second stage
43.1
Nonreassuring fetal status
24.2
Severe PIH†
33.3
Numbers of forceps traction applications
1
34.5
2
42.9
≥3
22.2

Dehiscence andmaternal injury
except for perineal
lacerations(n = 5)
%
P

P

%

P

0.85

16.7
12.5
16.7

0.73

5.3
7.1
0.0

0.15

11.3
20.8

0.31

0.56

Neonatalfacial injuries(n = 16)

Umbilical arteryacidemia(n = 8)

%

P

%

P

>0.99

25.0
26.3
16.7

0.56

10.5
8.9
8.3

>0.99

4.0
6.5

>0.99

12.0
21.0

0.54

4.0
11.3

0.43

12.7
0.44
20.0

6.9
0.0

0.39

20.8
6.7

0.29

9.3
6.7

>0.99

0.15

16.7
12.0

0.55

2.7
8.0

0.30

32.4
8.0

0.005∗

5.4
12.0

0.46

>0.99

12.0
14.8

>0.99

8.0
4.8

0.63

28.0
14.5

0.22

4.0
11.3

0.43

0.46

37.5
10.4

0.064

0.0
6.4

>0.99

12.5
19.2

1

0.0
10.3

>0.99

>0.99

7.1
15.3

0.70

0.0
6.9

0.59

21.4
17.8

0.72

7.1
9.6

>0.99

0.12

10.3
17.0

0.54

6.3
5.1

>0.99

25.0
10.3

0.099

6.3
12.8

0.46

0.79

22.2
11.8

0.27

1.1
4.4

0.28

22.2
17.4

0.74

5.6
10.1

>0.99

0.51

5.7
19.6

0.12

8.6
3.9

0.39

20.0
0.79
17.3

2.9
13.5

0.14

0.56

7.1
15.3

0.69

0.0
6.9

0.59

64.3
<0.001∗
9.6

7.1
9.6

>0.99

0.26

14.3
14.0

>0.99

4.7
7.0

>0.99

20.9
0.79
16.3

11.6
7.0

0.71

0.11

16.0
12.1
0.0

0.85

5.9
3.0
0.0

>0.99

23.5
6.1 0.053
66.7

2.0
∗
26.9 0.0053
0.0

0.58

16.7
14.3
0.0

0.58

7.3
4.8
0.0

>0.99

7.3
19.0
88.9

5.5
14.3
22.2

Percentages mean proportions of the morbidity in each factor. P values were calculated using Fisher’s exact test.
BMI: body mass index; PIH: pregnancy-induced hypertension.
∗
Statistically significant.
†Chief indication of severe PIH was excluded from the statistical test because of the lack of the cases (n = 3).

<0.001∗

0.14

6

Journal of Pregnancy
Odds ratios for 2 or more traction applications

Odds ratios for 3 or more traction applications

Age ≥35 years
Nullipara
Maternal complications
Maternal body height <155 cm

Maternal BMI at labor ≥29
Neonatal birth weight ≥3500 g
3.3

Augmentation
Epidural analgesia
Episiotomy

5.5

Fetal head malrotation

20

2.9

Station ≤+2
Chief indication of nonreassuring fetal status
0.1

1

10

0.01

0.1

1

10

100

Figure 2: Crude odds ratios for two or more and three or more traction applications. Horizontal bars indicate 95% confidence intervals. BMI:
body mass index.

as facial nerve palsy [21], depressed skull fracture [22], andcorneal abrasion [23]. If the Kielland rotational forceps can beused in the given situation, using it prior to Naegele forceps
may reduce the risk of neonatal head damage. The lead author
suggests four important points that a forceps operator should
recognize: accurate diagnosis of fetal head position including
rotation and station, gentle traction, anticipation of potential
risks in each case before forceps trial, and decisiveness forhalting the forceps trial if descent is not detected.
As described here, the lead author gives priority toforceps delivery for operative vaginal delivery. In the author’s
opinion, particularly for the fetus and neonates, excessive
stress can be avoided not only in cases with successful forceps
delivery but also in cases with failed forceps delivery, as
compared to cases with vacuum extraction. The reasons are
relatively short traction-to-delivery time, no need of uterine
fundal pressure maneuvers, and even in failure cases thepossibility of an early decision to halt the forceps trial. Excessive pulls of vacuum extraction with uterine fundal pressure
maneuvers may lead to infant cerebral palsy and uterine
rupture [24]. We hope that the value of forceps delivery will be
rerecognized and that many obstetric residents will be given
the chance of training in the method and technique of forceps
delivery.

References

Disclosure[8] H. Minakami, Y. Hiramatsu, M. Koresawa et al., “Guidelines forobstetrical practice in Japan: Japan Society of Obstetrics andGynecology (JSOG) and Japan Association of Obstetricians andGynecologists (JAOG) 2011 edition,” The Journal of Obstetrics
and Gynaecology Research, vol. 37, no. 9, pp. 1174–1197, 2011.

The summary of this report was presented at the 67th
Academic Conference of the Japan Society of Obstetrics andGynecology, Yokohama, Japan, 2015.

Conflict of Interests
The authors have no conflict of interests to declare.

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7

Journal of Pregnancy
Volume 2015, Article ID 483195, 7 pages
http://dx.doi.org/10.1155/2015/483195

Original article
Naegele forceps delivery and association between morbidity and the number offorceps traction applications: a retrospective study

同一術者によるネーゲリ鉗子分娩の実際，ならびに牽引回数を含めた因子と転帰との関連：
87 例の後方視的研究
松本直樹，竹中俊文，池田申之，矢﨑聡，佐藤雄一

日本語要旨【目的】 鉗子分娩（FD）には吸引分娩に比べ成功率が高い，児の合併症が少ない，産道損傷が多いという特性がある。筆頭著者は FD の優位点を重視して第一選択の急速遂娩法としている。ネーゲリ鉗子を主に用い低在横定位を含む回旋異常の場合にも使用する。娩出までに複数回の牽引を要することもある。本研究の目的は筆頭著者が行ったネーゲリ FD の実際と転帰を示すこと，牽引回数を含めた因子と転帰との関連を示すことである。
【方法】 FD の適応は日本産科婦人科学会の示すガイドラインに従った。牽引開始の児頭下降度はステーション+2 以上，鉗子は骨盤装着，牽引はゆっくり優しく行うこと原則とした。過去 2 年間に筆頭演者がネーゲ
リ FD を実施した 87 例を研究対象とした。牽引回数を含めた因子および転帰（FD の成功，短期的な有害事象）を後方視的に調査した。各因子と転帰との関連，各因子と牽引回数との関連を検証した。統計手法は単変量解析を用いた。
【結果】 FD の適応は分娩停止 59%，胎児機能不全 38%，妊娠高血圧 3%。牽引回数は 1 回 65%，2 回 25%，
3 回以上 10%。FD は全例で成功した。重大な母体・新生児の有害事象はなかった。新生児顔面損傷は回旋異常，牽引回数の増加，母体合併症ありで多くみられ，低臍帯動脈血 pH は胎児機能不全の適応で多くみられた。牽引 2 回以上のオッズ比は回旋異常 5.5，誘発促進 3.3，児頭下降度≦+2 2.9，牽引 3 回以上のオッズ比は回旋異常 20 であった。
【結論】 本研究で示した手続きによるネーゲリ FD は安全かつ成功率が高い器械分娩法であるが，特に回旋異常例などで複数回の牽引を要することもある。回旋異常と牽引回数の増加は重大な新生児有害事象につながり得るので慎重な実施が必要である。