AUTHOR AND EDITOR INFORMATION

Section 1 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

INTRODUCTION

Section 2 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Forceps are instruments designed to aid in the delivery of the fetus by applying traction to the fetal head. Many different types of forceps have been described and developed throughout time. Generally, forceps consist of 2 mirror image metal instruments that are maneuvered to cradle the fetal head and are articulated, after which traction is applied to effect delivery.

Forceps have 4 major components, as follows:

• Blades: The blades grasp the fetus. Each blade has a curve to fit around the fetal head. The blades are oval or elliptical and can be fenestrated (with a hole in the middle) or solid. Many blades are also curved in a plane 90° from the cephalic curve to fit the maternal pelvis (pelvic curve).


• Shanks: The shanks connect the blades to the handles and provide the length of the device. They are either parallel or crossing.


• Lock: The lock is the articulation between the shanks. Many different types have been designed.


• Handles: The handles are where the operator holds the device and applies traction to the fetal head.

History of the Procedure

The history of obstetrical forceps is long and, often, colorful. Sanskrit writings from approximately 1500 BC contain evidence of single and paired instruments; Egyptian, Greek, Roman, and Persian writings and pictures refer to forceps that were originally used for extraction following fetal demise to save the mother’s life.  

The credit for the invention of the precursor of the modern forceps to be used on live infants goes to Peter Chamberlen of England (circa 1600). Modifications have led to more than 700 different types and shapes of forceps. In 1745, William Smellie described the accurate application to the occiput, rather than the previously performed pelvic application, regardless of the position of the head. In 1845, Sir James Simpson developed a forceps that was designed to appropriately fit both cephalic curvatures and pelvic curvatures. In 1920, Joseph DeLee further modified that instrument and advocated the prophylactic forceps delivery. In an era in which many women labored and delivered under heavy sedation, forceps deliveries became common.

In current obstetrical practice, the use of forceps has become much less common. Clinical studies performed before the 1970s suggested that the risk of fetal morbidity and mortality was higher when the second stage of labor exceeded 2 hours.¹ With contemporary obstetrical management, morbidity rates no longer increase with longer labors if fetal surveillance is reassuring. Thus, the length of the second stage of labor alone is no longer an absolute indication for operative termination of labor.

Other factors were also at work to decrease the use of forceps deliveries. In particular, the availability of blood products and greater choices in antibiotics helped make the cesarean delivery a safe alternative to operative vaginal deliveries. In the 1980s, information became available suggesting that some forceps deliveries (midforceps deliveries) may have been associated with long-term adverse consequences to the fetus. These factors combined to greatly reduce the appeal of forceps delivery.

Currently, many obstetrical training programs in North America struggle to teach forceps delivery. Problems include the lack of adequate personnel comfortable with teaching forceps-assisted vaginal deliveries, changes in consumer attitudes, and the demand for natural delivery. In addition, many practitioners fear litigation if a forceps-assisted delivery results in a poor outcome.

Problem

See Indications.

Frequency

The frequency of operative vaginal deliveries is estimated to be 10% of all vaginal deliveries. Most of these are vacuum deliveries with forceps deliveries comprising about 3% of total deliveries. According to Bofill et al, trained fellows of the American College of Obstetricians and Gynecologists (ACOG) were more likely to be taught vacuum extraction, and they use vacuum extraction as their instrument of choice for operative vaginal deliveries.²

When forceps deliveries are performed, Simpson forceps (see Media file 1) is the instrument most commonly used for outlet- and low-forceps deliveries. Other types of forceps are also available; one specialized type is the Piper forceps, which is used in the delivery of the after-coming head in breech vaginal deliveries. It is designed to decrease traction on the fetal neck during breech delivery. Multiple other types of forceps have been designed to rotate the fetal head or for unusual maternal pelvic or fetal head shapes. For detailed information on other forceps procedures, the reader is directed to the book Dennen's Forceps Deliveries.¹

Clinical

Forceps delivery is classified according to the level and position of the head in the birth canal at the time the forceps are applied. In 1965, the ACOG issued a classification of low/outlet forceps, mid forceps, and high forceps. The low and outlet forceps categories were strictly defined and applied when the fetal scalp was visible, when the scalp had reached the pelvic floor, and when the sagittal suture was in the anteroposterior diameter of the pelvis. In contrast, the category of mid forceps was very broad. It included many stations of the fetal head, from engagement at zero station all the way to the perineum.

When the safety of midforceps deliveries came into question in the 1980s, the ACOG redefined the classification of station and types of forceps deliveries to better define which procedures posed a significant fetal risk.³ The revised classification uses the level of the leading bony point of the fetal head, in centimeters, measured from the level of the maternal ischial spines, to define station (-5 to 5 cm).

ACOG criteria for types of forceps deliveries

• Outlet forceps: (1) The scalp is visible at the introitus, without separating the labia. The fetal skull has reached the pelvic floor. (2) The sagittal suture is in anteroposterior diameter, right or left occiput anterior or posterior position (ie, the fetal head is at or on the perineum and rotation does not exceed 45º).


• Low forceps: The leading point of the fetal skull is at a station greater than or equal to +2 cm and is not on the pelvic floor; any degree of rotation may be present.


• Mid forceps: The station is above +2 cm, but the head is engaged.


• High forceps: This is not included in the classification. Previous systems classified high-forceps deliveries as procedures performed when the head is not engaged. High-forceps deliveries are not recommended.

Obstetrical pelvic evaluation and its clinical implications

The important points of interest are emphasized as follows:

• For obstetrical purposes, the coccygeal mobility and the narrowness of the subpubic arch should be evaluated during the pelvic examination.


• The distance between the bottom of the symphysis pubis and the sacral promontory is measured by digital examination and is defined as the diagonal conjugate.


• The obstetrical conjugate, the distance from the mid symphysis to the sacral promontory, is estimated by subtracting 1.5-2 cm from the diagonal conjugate. This is used to assess the capability of the presenting part to pass through the pelvic inlet. Unfortunately, no clinical means are available to directly measure the mid pelvis; these measurements can only be obtained with detailed imaging studies.


• Assessing the pelvic outlet is also important. The distance between the ischial tuberosities can be assessed during the pelvic examination and should be at least 8 cm.


• During the examination, one may have a high index of suspicion of a contracted mid pelvis if the ischial spines feel prominent, the sidewalls are convergent, and the concavity of the sacrum is very shallow.


• For the purpose of assessing a patient for forceps application, the best time to evaluate the pelvis is at the time of delivery, not at the first prenatal visit.

INDICATIONS

Section 3 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Indications for operative vaginal deliveries are identical for forceps and vacuum extractors. No indication for operative vaginal delivery is absolute.

The following indications apply when no contraindications exist:

• Prolonged second stage: This includes nulliparous woman with failure to deliver after 2 hours without, and 3 hours with, conduction anesthesia. It also includes multiparous woman with failure to deliver after 1 hour without, and 2 hours with, conduction anesthesia.

• Suspicion of immediate or potential fetal compromise in the second stage of labor.

• Shortening of the second stage for maternal benefits: Maternal indications include, but are not limited to, exhaustion, bleeding, cardiac or pulmonary disease, and history of spontaneous pneumothorax.

• In expert hands, fetal malpositions, including the after-coming head in breech vaginal delivery, can be indications for forceps delivery.

Prerequisites for forceps delivery include the following:

• The head must be engaged.

• The cervix must be fully dilated and retracted.

• The position of the head must be known.

• The type of pelvis should be known.

• The membranes must be ruptured.

• No disproportion should be suspected between the size of the head and the size of the pelvic inlet and mid pelvis.

• The patient must have adequate anesthesia.

• Adequate facilities and supportive elements should be available.

• The operator should be fully competent in the use of the instruments and the recognition and management of potential complications. The operator should also know when to stop so as not to force the issue.

RELEVANT ANATOMY

Section 4 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Planes and diameters of the pelvis

For obstetrical purposes, the pelvis is described as having 3 imaginary planes: plane of the inlet, plane of the mid pelvis, and plane of the pelvic outlet (see Media files 2-4).

• Plane of the inlet: Four diameters have been described.
• • Anteroposterior diameter: This is the distance between the sacral promontory and the symphysis pubis; it is designated the obstetrical conjugate. This conjugate normally measures approximately 10 cm or more, but it may be shortened considerably in an abnormal pelvis.
  
  
  • Transverse diameter: This is the greatest distance between the linea terminalis on either side of the pelvis. This imaginary line usually intersects the obstetrical conjugate at a point approximately 4 cm in front of the promontory.
  
  
  • Two oblique diameters: Each of these diameters extends from one of the sacroiliac joints to the iliopectineal eminence on the opposite side of the pelvis. These diameters normally average less than 13 cm each.


• Plane of the mid pelvis: This is the plane of the smallest dimensions. This plane is extremely important following engagement of the head in obstructed labor. The interspinous diameter (usually >10 cm) is the smallest diameter of the pelvis.


• Plane of the pelvic outlet: This consists of 2 triangular areas created from the connection of an imaginary line between the 2 ischial tuberosities. The apex of the posterior triangle is at the tip of the sacrum, and the apex of the anterior triangle is under the pubic arch. The following 3 diameters of the outlet are of importance:
• • Anteroposterior diameter: This is normally 9.5-11.5 cm and extends from the lower margin of the symphysis pubis to the tip of the sacrum.
  
  
  • Transverse diameter: This is commonly 11 cm and is the distance between the inner edges of the ischial tuberosities.
  
  
  • Posterior sagittal diameter: This usually exceeds 7 cm and extends from the tip of the sacrum to a right-angle intersection with the line between the ischial tuberosities.

Relevant terminology

• Engagement: This occurs when the biparietal diameter in a vertex position passes through the plane of the pelvic inlet. Thus, the widest part of the fetal head has entered the true pelvis. Engagement is generally achieved when the leading bony point of the skull has reached the level of the ischial spines (0 station).


• Presentation: This is the description of the presenting fetal part occupying the maternal pelvic inlet (eg, cephalic, breech, shoulder).


• Lie: This term describes the relationship between the fetal longitudinal axis and the maternal longitudinal axis (eg, longitudinal, oblique, transverse).


• Position: This term describes the relationship of the fetal presenting part to the maternal pelvis.


• Asynclitism: This term describes the condition when the fetal head is turned in the maternal pelvis such that one parietal bone is closer to the pelvic outlet.

Determination of position

• For cephalic presentations, the reference point is the occiput, whereas in breech presentations, the reference point is the sacrum.


• Position is always described in reference to the maternal right or left side of the pelvis.


• Determination of the position is crucial in forceps application and traction. The fontanels and sutures are used to determine the position. The finding that the fontanels are not easily palpable is not uncommon; this may occur because of distortion, molding, or caput formation.


• The position can be determined by finding the location of the sagittal suture and its relationship to the posterior portion of the ear, if palpable. If the sagittal suture is in a U formation, an anterior asynclitism presentation often occurs (ie, presentation of the anterior parietal bone of the fetal head). Conversely, if the sagittal suture is in the shape of an inverted U, this may indicate posterior asynclitism (ie, posterior parietal bone) presentation.


• Most fetuses can be delivered by forceps if they are in or can be maneuvered (manually or by forceps) into an occiput anterior or posterior position.


• Correct determination of the position may be the most important step prior to forceps application.

CONTRAINDICATIONS

Section 5 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

The following are contraindications to forceps-assisted vaginal deliveries:

• Any contraindication to vaginal delivery (see Normal Labor and Delivery)


• Refusal of the patient to verbally consent to the procedure


• Cervix not fully dilated or retracted


• Inability to determine the presentation and fetal head position or pelvic adequacy


• Confirmed cephalopelvic disproportion


• Unsuccessful trial of vacuum extraction (relative contraindication)


• Absence of adequate anesthesia/analgesia


• Inadequate facilities and support staff


• Inexperienced operator

WORKUP

Section 6 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Imaging Studies

• The decision for forceps delivery is often made in the second stage of labor when transport of the mother to other units is not practical and imaging studies may not be available quickly enough.


• Although x-ray pelvimetry and pelvic MRI and CT scan have been shown to help in defining the pelvic anatomy, their usefulness has not been demonstrated in predicting successful vaginal delivery.


• Ultrasonographic evaluation of the fetus may be of value in gathering information prior to a forceps delivery. Ultrasonography can be used to estimate fetal size as well as to assess the position of the fetal head.

TREATMENT

Section 7 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Preoperative details

Reviewing the indications for operative vaginal delivery and confirming the presence of all the prerequisites for forceps application are crucial steps. In particular, the presentation, position, and station of the presenting part must be reconfirmed just before the procedure.

Maternal verbal consent should be obtained prior to the forceps attempt, although the procedure may need to be performed emergently or after the mother has been medicated. If a planned forceps delivery is to be performed (ie, for maternal medical indications), counseling and consent may be completed prior to the onset of active labor.

The type of forceps to be used depends on the specific indications and conditions. The most commonly used forceps are Simpson forceps, which are used to deliver a molded fetal head, as is commonly seen in nulliparous women. Also commonly used are Tucker-McLane forceps, which have a more rounded cephalic curve, more suitable for the unmolded fetal head commonly seen in multiparous women. Many operators now use the Simpson forceps with the Luikart modification (semifenestrated).

The decision of what type of anesthesia is used should be made before initiating the delivery. An adequate level of anesthesia should be in effect before forceps application. Although published reports suggest that using only local infiltration anesthesia to the perineal body is enough, the authors believe that this type of anesthesia is far less than adequate. Very few women can tolerate forceps application without, at a minimum, pudendal block anesthesia. Attempts to "force the issue" with inadequate anesthesia may be intolerable to the mother. Pudendal block anesthesia may be augmented with intravenous sedation.

Adequate anesthesia is also achievable with regional or general anesthesia. Regional anesthesia is often used; general anesthesia is usually reserved for very unusual emergency situations. With the former, the patient should be prepared and draped after the anesthesia has been delivered via epidural or spinal injection. With the latter, the surgeon should be ready, with the patient properly draped, before administration of general anesthesia.

The bladder should be emptied in preparation for forceps operative deliveries, regardless of the type of anesthesia used.

Intraoperative details

Application of the forceps

The most crucial point of forceps delivery is precise knowledge of the presentation position of the fetus. The term pelvic application is used when the left blade is applied on the left side of the pelvis and the right blade is applied on the right side of the pelvis, regardless of the fetal position. A pelvic application may be appropriate in some instances, as in a direct occiput posterior presentation. Pelvic application is never to be used as a substitute for exact knowledge of the fetal position; inappropriate pelvic application may cause significant harm.

Once again, emphasizing that forceps delivery is skill- and training-dependent is important. The operator must have a clear understanding of his or her own capabilities, as well as the safe limits of the procedure, and must not exceed either of these.

Application technique

See Media files 5-13 for a pictorial demonstration of a simple outlet-forceps delivery for an occipitoanterior position.

After ensuring proper anesthesia and an empty bladder, the fetal position is again checked.

The presence of the sagittal suture in the anteroposterior diameter of the pelvic outlet is confirmed, and the left forceps blade is introduced into the posterior half of the left side of the pelvis and is guided to the appropriate position along the fetal head. The placement and guidance are performed by the operator's right hand in the maternal pelvis. The left blade is left in place to stand freely or is held in place without pressure by an assistant. The right blade is introduced into the right side of the pelvis in the same fashion.

At all times, attention should be given to avoiding the use of force. At the beginning of the application, the blades should be held like a pencil, almost in a vertical position; as the blades are introduced into the vagina, they are brought to a horizontal position. Avoiding levering or forcing the blade with the nonvaginal hand is critical. The fingers in the vagina should only guide the blades and should not apply pressure on or displace the fetal head. Forceps application is generally not performed during a uterine contraction; however, properly placed blades may be left in place if a contraction ensues during placement.

After proper placement of the left blade, it should lie almost parallel to the floor. With insertion of the right blade, the forceps should lock without pressure.

When the occiput is not directly anterior, applying the blade to the lower half of the fetal head first to avoid turning the head to a transverse position with the first blade application is desirable. At times, this requires placement of the right blade first.

Appropriateness of application

In a proper cephalic application, the long axis of the blades corresponds to the occipitomeatal diameter, with the ends of the blades lying over the posterior cheeks (see Media file 6); the blades should lie symmetrically on both sides of the head. The sagittal suture of the fetal head will be in the middle, and the blades will be equidistant from the sagittal and occipital sutures. At no time should any part of the forceps cover any midline structure. The forceps should lock easily without any force and stand parallel to the plane of the floor. The appropriateness of application should be confirmed before applying traction.

Traction with forceps and episiotomy

During an indicated forceps delivery, traction is applied during contractions. The instrument may be used to maintain the station of the fetal head between contractions. In an emergency, applying continuous traction may be necessary until the fetal head delivers.

After confirming proper forceps application, traction starts parallel to the plane of horizon and is then elevated to an almost vertical position as the fetal head extends (see Media file 6). The amount of traction should be the least necessary to accomplish safe fetal head descent. In biomechanical studies, safe limits of 45 pounds in primiparas and 30 pounds in multiparas have been suggested; however, if care is not taken, these limits can easily be exceeded by most physicians.⁴ The angle of traction is as important as the force applied in effecting delivery. Knowing when to stop and abandon the procedure is a matter of experience. Assuming that everything has been done according to proper protocols and no progress is observable in 3 traction attempts, operative vaginal delivery may be discontinued and preparation for abdominal delivery should start as soon as possible.

Episiotomy may be performed when the perineum is distended by the fetal head. With forceps delivery, less opportunity exists for the maternal tissues to stretch, and episiotomy may be performed to allow a more rapid delivery. The utility of episiotomy in preventing short- and long-term maternal injury is controversial.⁵

Postoperative details

After a forceps delivery, thorough examination of both the mother and the newborn is advisable. Maternal cervical, vaginal, and perineal lacerations must be excluded. In addition, maternal vulvar edema may be significant. Most operators institute measures such as perineal ice to ameliorate this. Pain medication is also advisable. These patients are at increased risk for hemorrhage, and a postoperative hemogram should be obtained and the condition corrected as needed.

Before discharge, pelvic and rectal examinations may help confirm the integrity of pelvic organs and may exclude such entities as pelvic hematoma, rectal tears, and misplaced sutures. Diagnostic studies should be obtained as needed.

The newborn must be examined for lacerations, bruising, and other injuries. The pediatric service should be made aware of the circumstances of delivery.

Follow-up

In the absence of specific forceps-related complications, a follow-up postpartum examination within 4-6 weeks, with a thorough pelvic examination, is usually sufficient.

COMPLICATIONS

Section 8 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Research into forceps delivery complications is hampered by a number of potential biases—most importantly, the lack of an appropriate comparison group. Maternal and fetal complications have been reported to vary depending on skill and judgment of the operator. The following are complications associated with forceps-assisted vaginal deliveries:

• Maternal complications
  • Early (ie, acute) complications include (1) lacerations to the cervix, vagina, perineum, or bladder; (2) extension of episiotomies; (3) increase in blood loss; (4) hematomas; and (5) intrapartum rupture of the unscarred uterus.

  • Late complications are mainly related to injury to the pelvic support tissues and organs and include (1) urinary stress incontinence, (2) fecal incontinence, (3), anal sphincter injuries, and (4) pelvic organ prolapse.

• Fetal complications
  • Transient facial forceps marks, bruising, lacerations, and cephalohematomas are possible.

  • Facial nerve injuries may be seen.

  • Skull fractures, intracranial hemorrhage with falx, or tentorial lacerations have also been reported.

  • Reports exist of an increased incidence of shoulder dystocia in patients delivered with forceps, although this has not been confirmed in other studies.

  • Cerebral palsy, mental retardation, and behavioral problems may be more related to hypoxic episodes that required emergent delivery or other intrapartum, environmental, or congenital factors.

OUTCOME AND PROGNOSIS

Section 9 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Research on the outcome and prognosis of forceps delivery has been less than complete. However, in randomized trials⁶ comparing elective low-forceps delivery with normal spontaneous deliveries, maternal and neonatal outcomes revealed no differences between the 2 groups. As expected, the mean time to delivery was shorter in the forceps group.

Another larger randomized study⁷ comparing outlet-forceps delivery with spontaneous delivery showed that forceps delivery had no immediate adverse neonatal effects and no significant shortening of the second stage of labor was present; however, the risk of maternal perineal trauma in the forceps group was increased among primiparous women.

In another randomized prospective study⁸, the newborn head circumference-to-width ratio, hearing, or vision was shown not to be statistically different in neonates delivered by forceps compared with neonates born by spontaneous vaginal delivery.

Forceps deliveries performed emergently are more likely to be associated with a poor fetal outcome; however, information is not available as to whether these outcomes could be improved by other delivery methods.

The ultimate outcome of forceps deliveries depends on numerous factors, and among the most important of these remain the skill and judgment of the operator. The operator must be supported by a skilled team, including anesthesia and nursing staff. The presence of a person skilled in newborn resuscitation is also mandatory for operative vaginal deliveries.

FUTURE AND CONTROVERSIES

Section 10 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

The future of forceps deliveries is in doubt. Information developed in the 1980s suggests that fetal outcome may be poor after at least some forceps deliveries. Other data suggest that long-term compromise of the maternal rectal sphincter is a common sequela of forceps delivery. In view of the discussions of the merits of cesarean delivery on demand for preservation of maternal pelvic musculature, the place of forceps deliveries in obstetrical practices has been questioned.

Concerns about the appropriateness of forceps delivery have led to increased concern among practitioners about the medicolegal liability involved in forceps delivery. Among other effects, this has led to a marked decrease in the training of new physicians to perform these deliveries. Given these trends, clinician educators have addressed the need to continue training programs in operative forceps deliveries.

MULTIMEDIA

Section 11 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Media file 1:  An illustration of Simpson forceps.
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Media file 2:  The anterior view of a pelvis.
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Media file 3:  The inferior view of a pelvis.
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Media file 4:  The sagittal section of a pelvis.
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Media file 5:  An illustration of a forceps delivery technique.
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Media file 6:  The left handle is held in the left hand (Simpson forceps).
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Media file 7:  The left blade is introduced into the left side of the pelvis.
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Media file 8:  The left blade is in place and the right blade is introduced by the right hand.
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Media file 9:  A median or mediolateral episiotomy may be performed at this point. A left mediolateral episiotomy is shown here.
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Media file 10:  The forceps have been locked. The inset shows a left occipitoanterior fetal position.
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Media file 11:  An illustration of horizontal traction with the operator seated.
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Media file 12:  An illustration of upward traction.
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Media file 13:  An illustration of disarticulation of the branches of the forceps; beginning modified Ritgen maneuver.
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REFERENCES

Section 12 of 12

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

1. Dennen PC. Dennen's Forceps Deliveries. 3^rd ed. Philadelphia, Pa: FA Davis; 1989.
2. Bofill JA, Rust OA, Perry KG, et al. Operative vaginal delivery: a survey of fellows of ACOG. Obstet Gynecol. Dec 1996;88(6):1007-10. [Medline].
3. American College of Obstetricians and Gynecologists. American College of Obstetricians and Gynecologists Practice Bulletin. Operative Vaginal Delivery. Washington, DC: American College of Obstetricians and Gynecologists; June, 2000.
4. Leslie KK, Dipasquale-Lehnerz P, Smith M. Obstetric forceps training using visual feedback and the isometric strength testing unit. Obstet Gynecol. Feb 2005;105(2):377-82. [Medline].
5. Youssef R, Ramalingam U, Macleod M, Murphy DJ. Cohort study of maternal and neonatal morbidity in relation to use of episiotomy at instrumental vaginal delivery. BJOG. Jul 2005;112(7):941-5. [Medline].
6. Carmona F, Martinez-Roman S, Manau D, et al. Immediate maternal and neonatal effects of low-forceps delivery according to the new criteria of The American College of Obstetricians and Gynecologists compared with spontaneous vaginal delivery in term pregnancies. Am J Obstet Gynecol. Jul 1995;173(1):55-9. [Medline].
7. Yancey MK, Herpolsheimer A, Jordan GD, et al. Maternal and neonatal effects of outlet forceps delivery compared with spontaneous vaginal delivery in term pregnancies. Obstet Gynecol. Oct 1991;78(4):646-50. [Medline].
8. Carmody F, Grant A, Mutch L, et al. Follow up of babies delivered in a randomized controlled comparison of vacuum extraction and forceps delivery. Acta Obstet Gynecol Scand. 1986;65(7):763-6. [Medline].
9. Netter FH, Dalley AF, eds. Atlas of Human Anatomy. 2^nd ed. Teterboro, NJ: Icon Learning Systems; 1998.
10. Handa VL, Harris TA, Ostergard DR. Protecting the pelvic floor: obstetric management to prevent incontinence and pelvic organ prolapse. Obstet Gynecol. Sep 1996;88(3):470-8. [Medline].
11. Liabsuetrakul T, Choobun T, Peeyananjarassri K, Islam M. Antibiotic prophylaxis for operative vaginal delivery. Cochrane Database Syst Rev. 2004;CD004455. [Medline].
12. Meyer S, Schreyer A, De Grandi P, Hohlfeld P. The effects of birth on urinary continence mechanisms and other pelvic- floor characteristics. Obstet Gynecol. Oct 1998;92(4 Pt 1):613-8. [Medline].
13. Miller DA, Goodwin TM, Gherman RB, Paul RH. Intrapartum rupture of the unscarred uterus. Obstet Gynecol. May 1997;89(5 Pt 1):671-3. [Medline].
14. Patel RR, Murphy DJ. Forceps delivery in modern obstetric practice. BMJ. May 29 2004;328(7451):1302-5. [Medline].
15. Ramin SM, Little BB, Gilstrap LC 3rd. Survey of forceps delivery in North America in 1990. Obstet Gynecol. Feb 1993;81(2):307-11. [Medline].
16. Ventura SJ, Martin JA, Curtin SC, Mathews TJ. Births: final data for 1997. Natl Vital Stat Rep. Apr 29 1999;47(18):1-96. [Medline].
17. Cunningham FG, Gant NF, Leveno KJ, et al, eds. Williams Obstetrics. 19^th ed. Norwalk, Conn: Appleton & Lange; 1993.

Article Last Updated: May 21, 2007