Types of forceps
Conditions for forceps
Positioning the forceps
Delivering the baby
Things to consider
Types of forceps
The selection of forceps
are made of metal, and are actually 2 separate pieces that look like a pair of salad servers. When the forceps are correctly positioned on the baby's head, the handles then lock in together to provide a protective cage around the baby's head, thus preventing excessive pressure being applied, as the baby is being born. The arms (or handles) of the forceps become neatly aligned for the caregiver to hold onto, each arm is marked 'L' (left) and 'R' (right). They extend and are curved in shape, to correspond with the woman's pelvic curve, and end in cupped, hand-like shapes (known as 'blades') that fit over the sides of the baby's head.
Image 6-51 shows a set of forceps.
There have been over 700 different types of forceps developed over the years, with a variety of shapes, sizes and lengths, generally aimed at dealing with a particular complication, or a caregiver's preference. (It seems like many obstetricians wanted to have their own, like having a tailor-made golf club!).
They have all been given names after the person who designed them. Some of the more common forceps used in Australia, and their abbreviations when written, include Wrigley's (or a Wrigley's lift out written as WLO), Neville-Barnes Forceps (NBF), Haig Ferguson's Delivery (HFD), Simpson's (SFD) and if the baby is in a posterior position, then the Kielland is often used (called a Kielland's Rotation and Delivery or KRD). You may hear these names being discussed in the delivery suite, or they could be written on your medical records, or your next pregnancy's antenatal card, to describe the 'type of birth' you had.
Some names of commonly used forceps in America and Europe include Elliot's, Milne- Murray (MM), Anderson's, Tucker-Mclane's, Barton's or Piper's (the latter designed especially for breech deliveries).
The selection of forceps
will depend on how far the baby's head has descended down the woman's birth canal, the position of the baby's head and your caregiver's preference. The main aspect to consider when deciding if forceps are appropriate (and which type of forceps to use), relate to how high the baby's head is in the woman's pelvis.
The types of forceps are:
In past generations, it would not have been unusual for a baby whose head was not engaged (or sitting high up in the lower section of the uterus), to be delivered with a 'high forceps', (meaning that the forceps needed to be placed further up the vagina, inside the uterus). If you had an internal vaginal examination, your caregiver would only just be able to reach the baby's head at this level. This practice is now considered too risky, as it can often lead to injuring the woman and / or the baby. These days a Caesarean would be required, rather than attempting this.
Mid forceps are used when the baby's head is engaged, but is sitting higher than station +2 (or 2 centimetres below the ischial spines of the pelvis). Your caregiver would need to do an internal examination to feel the position of the baby's head but should be able to reach it easily. Neville-Barnes (known as NB) or Haig Ferguson's (HF), are commonly used for this.
Mid forceps can at times be attempted in the operating theatre, if your caregiver feels that the baby might not come down easily. If the delivery is tried, but appears to be too difficult, the forceps would be abandoned and a Caesarean would be performed. This is discussed in unsuccessful forceps and Caesarean.
Low forceps are the ones most commonly used today. The baby's head is below station +2, which is fairly low in the vaginal canal. Usually if the woman's labia are parted, the baby's head can be seen. Simpson's forceps are the most common type of low forceps used in Australia. Low forceps are usually able to successfully deliver the baby.
Outlet forceps are used when the baby's head can be easily seen at the opening of the woman's vagina, but the baby's head is not emerging any further. Wrigley's forceps are commonly used for this, but are now probably being replaced more by the use of a ventouse in recent years. Sometimes an episiotomy alone can help deliver the baby at this late stage, without the use of forceps or a ventouse.
Besides the engagement of the baby's head, the other aspect to consider when selecting forceps is when the baby needs to be turned (or rotated) from a posterior position. A baby in a posterior position can sometimes prevent the baby descending down the birth canal to be born. Rotational forceps (such as Kielland's) have straighter handles that are capable of having some 'slip' instead of locking together. They are used to turn the baby into a more favourable anterior position, and then traction is used with the same forceps to deliver the baby. You may wish to read Posterior position.
Most 'mid' 'low' and 'outlet' forceps are the non-rotational type, in that they are simply applied to the baby's head, and traction is used to bring the baby down the birth canal, without changing the position of the baby's head.
Last revised: Saturday, 8 December 2012
This article contains general information only and is not intended to replace advice from a qualified health professional.