A randomized prospective trial of the obstetric forceps versus the M-cup vacuum extractor. North Staffordshire/Wigan assisted delivery trial. A randomised prospective trial of the obstetric forceps versus vacuum extraction using defined criteria. Soft cup vacuum extraction: a comparison of outlet delivery. A prospective randomised controlled trial of the Kiwi Omnicup versus conventional ventouse cups for vacuum-assisted vaginal delivery. A randomized comparison of assisted vaginal delivery by obstetric forceps and polyethylene vacuum cup. A randomised controlled trial of a new handheld vacuum extraction device. A randomised prospective study comparing the new vacuum extractor policy with forceps delivery. [Comparative assessment of efficacy and safety of assisted vaginal delivery with forceps and with vacuum extractor].
Our purpose was to determine the efficacy of the obstetric forceps versus the M-cup, a new vacuum extractor cup, and maternal-neonatal complication rates.
                Over a 10-month period operative vaginal deliveries were randomized between the obstetric forceps and the M-cup vacuum extractor cup. Maternal demographics, indication for intervention, analgesia, position, station, degree of asynclitism, fetal caput-molding, and time from application to delivery were prospectively recorded. Episiotomy and extensions, lacerations, and the reason for abandonment of the randomized instrument were noted in both groups. Fetal weight, Apgar scores, cord arterial gases, hyperbilirubinemia, phototherapy, and any evidence of fetal trauma were documented at delivery or in the nursery.
                Six hundred thirty-seven women were randomized, 315 in the forceps group and 322 in the M-cup group. There were no differences in maternal demographic variables. The station, position, degree of asynclitism, or requirement for rotation was not different between the groups. The corrected efficacy rates were forceps 92% and M-cup 94% (p = 0.217). The M-cup deliveries were accomplished more rapidly than forceps deliveries (p < 0.001) and were associated with a lower rate of episiotomy (p < 0.001), third-degree (p < 0.001) and fourth-degree (p = 0.002) lacerations, but blood loss as clinically estimated (p = 0.232) or as measured by hemoglobin levels (p = 0.166) was not significantly different. Forceps deliveries were associated with fewer clinically diagnosed cephalhematomas (p = 0.015) than M-cup deliveries were, but there were no differences in the number of neonates diagnosed with hyperbilirubinemia (p = 0.377) or in the number of infants treated with phototherapy (p = 0.660).
                The M-cup vacuum extractor cup appears to be as efficient (and faster) than the obstetric forceps but is associated with significantly more fetal cephalhematomas, whereas maternal injuries are more common with the forceps. In a trial conducted at the North Staffordshire and Billinge Maternity Hospitals (NSMH and BMH) a total of 264 women who required an assisted delivery in the second stage of labour were randomly assigned to be delivered either by Kobayashi silicone cup ventouse or by forceps. A larger proportion (90%) of those assigned to the forceps group were actually delivered by the allocated instrument compared to those in the silicone cup group (73%). However, there was a significantly higher rate of maternal morbidity in terms of perineal trauma and discomfort in the forceps group. No differences in neonatal morbidity were detected. The objective of this study was to determine the safety of obstetrics forceps when used under strictly defined criteria compared to vacuum extraction for delivery in the second stage of labour. A randomised prospective trial was performed on 442 women undergoing instrumental delivery in the second stage. Two hundred and four women were in the forceps group and 238 in the vacuum group. When using forceps traction efforts to deliver the baby were kept to less than three and the head was always delivered in the occipito-anterior position. In the two groups there were no significant difference in the incidence of third-degree perineal tears, post-partum haemorrhage or ruptured uterus. Cervical tears were slightly higher in the forceps group. Babies delivered by vacuum extraction showed a higher incidence of cephalhaematomas. There was no significant difference in babies needing resuscitation at birth, admission to neonatal intensive care unit, stillbirth or neonatal death rates. The failure rate was significantly higher in the vacuum group. The time taken to complete the procedure was significantly less in the forceps group. Forceps deliveries when performed under defined criteria are as safe as vacuum deliveries to the mother with a lesser failure rate and a lower incidence of cephalhaematomas in the neonate compared with vacuum deliveries. One hundred eighteen nulliparous patients delivered under conduction anesthesia who met the standard criteria for low forceps delivery were randomly assigned to one of three groups to be delivered by low Tucker-McLane forceps, Silastic vacuum extraction system, or Mityvac vacuum extractor. Significant maternal soft tissue trauma was identified in 48.9% of the forceps group, 36.1% of the Silastic group, and 21.6% of the Mityvac group. Superficial fetal scalp changes were found in 71% of the forceps group, 44% of the Silastic group, and 46% of the Mityvac group. Of these, cephalhematomatas were noted in 2.2% of the forceps group, 13.9% of the Silastic group, and 16.2% of the Mityvac group. All three instruments were considered effective outlet delivery instruments. To evaluate the performance and safety of the Kiwi Omnicup and compare it to conventional vacuum cups in routine clinical practice.
                A randomised controlled trial of the Kiwi Omnicup versus conventional vacuum cups.
                Queen Charlotte's and Chelsea Hospital, a tertiary referral hospital in London from April 2001 to March 2004.
                Women requiring assisted vaginal delivery by ventouse.
                Women were randomised to the Kiwi Omnicup (n=206) or conventional vacuum cups (n=198). Data regarding maternal demographics, labour, mode of delivery and maternal and neonatal outcome were collected.
                Failure of delivery with instrument of first choice.
                The Kiwi Omnicup was less successful at delivery with instrument of first choice than the conventional ventouse, failure rate 30.1 versus 19.2% (RR 1.58; 95% CI 1.10-2.24). It was associated with a greater number of cup detachments (mean 0.68 compared with 0.28, with 44% compared with 18% having at least one detachment [P<0.0001]). There was no difference in the incidence of severe maternal trauma, and there were no cases of serious neonatal injury.
                The Kiwi Omnicup is less successful than conventional ventouse in achieving vaginal delivery, but its safety profile is comparable. The assisted vaginal delivery methods of rigid obstetric forceps and polyethylene vacuum cup extraction were compared in a prospective, randomized study. The 99 women studied had all completed 35 full weeks' gestation, required attempted assisted vaginal delivery, and were randomly assigned to either attempted forceps or vacuum-assisted delivery. All presentations were cephalic, with stations ranging from +1 to +4. Neonates were evaluated at 24 hours by neonatal staff. The infants underwent intracranial ultrasound screening during the first 24 hours of life and ophthalmologic examination within 48 hours. Vaginal delivery was successful with the intended method in 83% of vacuum-assisted deliveries and in 78% of forceps deliveries (not statistically significant). Neonatal retinal hemorrhage was found in 17 and 38% (P less than .043) of the randomized forceps and vacuum deliveries, respectively. No intraventricular hemorrhage was found. Apart from associations between vacuum-assisted delivery and mild hyperbilirubinemia and neonatal retinal hemorrhage (of uncertain clinical significance), and between assisted forceps delivery and an increased potential for facial injury, neonatal outcomes did not differ significantly. Maternal outcomes also did not differ significantly. No significant differences in safety or efficacy were found between polyethylene cup vacuum extraction and rigid obstetric forceps-assisted vaginal delivery in this population of predominantly low-pelvic assisted deliveries. Patients delivered by sequential use of forceps after vacuum or by vacuum after failed forceps application did not suffer significantly increased morbidity relative to those delivered by forceps or vacuum alone. Use of alternate or sequential methods allowed an overall cesarean rate of 3% in this population. To evaluate the effectiveness of a new handheld vacuum delivery device.
                Randomised controlled trial.
                Southmead Hospital, Bristol, UK.
                One hundred and ninety-four women requiring delivery with vacuum extraction.
                Women were recruited into the study while still in early labour. If during delivery, vacuum extraction was indicated they were then randomly allocated to either a new handheld vacuum device, the Kiwi Omnicup, or to a 'standard' vacuum cup selected by the obstetrician. The 'standard group' consisted of the silastic (66/98, 67%) or the metal cups (32/98, 33%). Study data were recorded at completion of the delivery and at 24-48 hours. An additional brief symptom questionnaire was completed by the mother at 10 days postnatally. Statistical analyses were done on an 'intention-to-treat' basis.
                The primary outcome was the successful completion of delivery with the allocated instrument. Secondary outcomes were substantial fetal scalp trauma and substantial maternal trauma.
                The Omnicup was associated with a significantly higher failure rate than the standard cup [34%vs 21%, odds ratio (OR) = 1.9 (1.01-3.6)]. This difference persisted after adjusting for confounding factors [adjusted OR = 2.25 (1.01-5.0)] and resulted in significantly more forceps deliveries in the Kiwi Omnicup group [22%vs 10%, unadjusted OR = 2.5 (1.1-5.5)]. The caesarean section rates were similar in both groups [9.4%vs 8.2%, OR = 1.2 (0.4-3.2)]. Rates of substantial scalp trauma and maternal trauma were similar in both groups. However, there were more cases of jaundice in the standard cup group [2.3%vs 12.0%, unadjusted OR = 0.18 (0.04-0.82) and adjusted OR = 0.10 (0.01-0.88)].
                The Omnicup is not as successful at achieving a vaginal delivery as the combination of the currently used vacuum cups. To compare assisted vaginal delivery by forceps with delivery by vacuum extractor, where a new vacuum extractor policy was employed which dictated the cup to be used in specific situations.
                Multicentre randomised controlled trial.
                Four district general hospitals in the West Midlands.
                Six hundred-seven women requiring assisted vaginal delivery, of whom 296 were allocated to vacuum extractor delivery and 311 to forceps.
                Delivery success rate, maternal perineal and vaginal injuries, maternal anaesthetic requirements, neonatal scalp and facial injuries.
                Of the vacuum extractor group, 85% were delivered by the allocated instrument compared to 90% in the forceps group (odds ratio (OR) 0.64; 95% confidence intervals (CI) 0.4-1.04). However, more women in the vacuum extractor group were delivered vaginally (98%) than in the forceps group (96%). There were significantly fewer women with anal sphincter damage or upper vaginal extensions in the vacuum extractor group (11% vs 17%, OR 0.6; 95% CI, 0.38-0.97). There were significantly fewer women in the vacuum extractor group requiring epidural or spinal anaesthetics (25.4% vs 32.7%, OR 0.69; 95% CI 0.49-0.99) or general anaesthetics (1% vs 4%, OR 0.17; 95% CI 0.04-0.76). Although there were significantly more babies in the vacuum extractor group with cephalhaematomata (9% vs 3%, OR 3.3; 95% CI 1.4-7.4) there were fewer babies in the vacuum extractor group with other facial injuries. There were three babies in the forceps group with unexplained neonatal convulsions.
                Assisted vaginal delivery using the new vacuum extractor policy is associated with significantly less maternal trauma than with forceps. Further studies are required to assess neonatal morbidity adequately. We performed a prospective, controlled, randomized trial to compare de safety and efficacy between the vaginal assisted delivery with vacum extractor forceps. We included a control group of primigravidae. We use the ACOG application criteria for operative obstetrics. We measured the differences in regard to indication for operative delivery, obstetric trauma and the general characteristics of the patients. A total of 210 patients were included which were distributed in three groups. In the first group we included the patients of vacum extractor, the second group of forceps and the third the control group. In our results we found no statistically significant differences among three groups in regard to the general characteristics and obstetric trauma. In the vacum extractor group we found six cefalohematomas (8.5%), two newborns with skin laceration (2.8%) and four newborns with cerebral edema (5.7%). In the forceps group we had two newborns diagnosed with cefalohematomas (2.8%), seven newborns with cerebral edema (10%) and scalp laceration on four newborns (6%). In the control group we found one cefalohematoma (1.4%) and cerebral edema in four newborns (5.7%). We did not find statistically significant differences when we compared the group of the vacum and the forceps.
                With this information we concluded that both instruments are equal in regard to efficacy and safety when they are use by experimented hands and following the application criteria. Nevertheless, there is a high incidence of vaginal injuries and obstetric trauma in the newborn in the operative delivery compared with the control group without an important increase in the perinatal mortality.
There is a recognised place for forceps and all types of ventouse in clinical practice. The role of operator training with any choice of instrument must be emphasised. The increasing risks of failed delivery with the chosen instrument from forceps to metal cup to hand-held to soft cup vacuum, and trade-offs between risks of maternal and neonatal trauma identified in this review need to be considered when choosing an instrument.