Forceps and vacuum extractors are the two instruments used in assisted vaginal delivery. Although the idea may be frightening, these instruments are very safe for both mother and baby when used by a skilled doctor in the right circumstances. In fact, forceps and vacuum can be crucial in helping deliver a baby who is not tolerating labour well. Thanks to these tools, many mothers have avoided caesarean section.
Forceps have been around for centuries. Variations of modern forceps were used as far back as 1500 BC. The modern version was developed in England during the 1600s. Primitive vacuum extractors were designed in the 18th century but not perfected until the 20th century.
Forceps or vacuum may be used if there is concern for baby or mother, if labour has stalled or the mother is too exhausted to push effectively. The choice of forceps or vacuum will depend on the doctor’s skill with each instrument, the unique circumstances of that delivery, and the mother’s preference after being informed of her options.
As many as one out of five of all deliveries in western Canada may require the use of either forceps or vacuum extractor. There are ways to reduce the chances of needing assisted vaginal delivery. Women who have a supportive birth companion during labour are less likely to need instruments to help deliver the baby. They also experience shorter labours with less need for pain relief and fewer episiotomies (a cut to the perineum, the area between the vagina and the anus).
Frequent changes in position, even during the pushing stage, also help. Waiting for the urge to push is important, as it results in more unassisted births. This is especially true when an epidural anaesthetic is used. Sometimes a woman’s natural contractions are not strong enough to deliver the baby. Since it is better to push rather than pull a baby out, giving the mother medication (oxytocin) may improve the strength of the contractions sufficiently.
If the doctor does recommend use of forceps or vacuum, there are guidelines in place to help the procedure go smoothly. The mother’s bladder should be empty, she should have adequate pain relief, and the position of the baby’s head must be known.
The sutures (small spaces between the baby’s skull bones) will be felt in order to correctly place the instrument. If the baby’s head is not low enough in the birth canal to allow the use of these instruments, the physician will likely recommend a caesarean section. Once the instrument is applied, the doctor pulls during a contraction to use the combined effort of both mother and doctor. This, along with the mother’s best effort to push, makes success more likely.
In some cases, the doctor will stop pulling. For instance, the baby’s head might not descend despite the extra help. As well, if the vacuum pops off repeatedly, delivery may be attempted using forceps or caesarean section.
Forceps may appear frightening since they are made from heavy surgical steel. In reality, they are very delicate instruments designed to cradle the baby’s head.
The two sides of the forceps are inserted into the vagina one at a time. They are positioned perfectly around the baby’s head. The physician checks in several ways to make sure the forceps are positioned correctly. As the mother pushes, the doctor guides the baby through the birth canal.
As in any type of delivery, complications can occur when using forceps. Since forceps fit around the outside of the baby’s head, more space is occupied during the move through the birth canal. As well, the baby’s head moves down faster than with the mother’s pushing alone, so her tissues have less time to stretch. As a result, there is a higher chance of episiotomy or significant tears to the mother’s perineum and vagina. Occasionally, there can even be tears into the rectum.
Swelling and pain can be worse after an assisted vaginal delivery. This may partly be due to the use of forceps, as well as if the mother pushed for a long time before their use. It can also be hard to pass urine for several hours after delivery. Some women may need to have a catheter (a small tube) inserted to empty the bladder for a little while.
Parents are often concerned about forceps hurting the baby. Problems are much more likely if the position of the forceps is not correct, if the baby is not low enough in the birth canal or if the doctor needs to use the forceps to reposition the baby’s head. Usually there are only slight red marks on the baby’s cheeks that last for a very short time. Sometimes the baby’s scalp or face may be bruised or mildly scraped. More rarely, the facial nerve may be damaged.
Cephalohematoma, a collection of blood next to the baby’s skull, is more common after the use of forceps than in normal birth. The baby may be at more risk of jaundice. However, cephalohematoma causes no long-term problems and will resolve on its own. Fortunately, severe bleeding and skull fractures are very rare.
Sometimes, the baby does not move down through the birth canal as expected with the forceps. Pulling harder could injure mother and baby. At this point, the doctor usually stops using forceps, and delivers the baby by caesarean section.
The vacuum extractor is used more often than the forceps, although in some situations forceps are more likely to be successful. Unlike forceps, which can be used to turn the baby, the vacuum can only be used to pull.
Many different types of vacuum suction cups exist, ranging from metal to soft plastic. In western Canada, soft plastic cups are most commonly used. Although rigid cups are more likely to be successful in delivering the baby, they are also more likely to injure the scalp. The vacuum pump that creates the vacuum in the suction cup may be hand-operated or electric. Electric pumps make more noise than hand-held versions, but both are capable of creating a vacuum seal on the baby’s head.
Although vacuum use does not lead to any facial injuries for baby, the scalp can be hurt. The chance of cephalohematoma is higher than with forceps. The mother usually experiences less trauma than with forceps, since the vacuum cup sits on top of the baby’s head and does not increase its size. Since birth is often a little slower with the vacuum, the mother’s tissues have a slightly greater chance to stretch. Babies born by vacuum have a higher chance of retinal bleeding (bleeding at the back of the eyes). There is no evidence that this is a long-term problem for babies. Again, more severe bleeding and skull fractures are very rare.
By far, the best way to give birth is by unassisted vaginal delivery. When this is not possible and vaginal birth is still the first choice, forceps and vacuum are available to help. Using proper technique, assisted by these instruments, is a safe way for your doctor to deliver your baby.