Optimal Fetal Positioning
What is Optimal Fetal Positioning?
This information is for expectant mothers and their partners to try and encourage your baby to go into the ideal position for birth before labour begins.
Optimal Fetal Positioning (OFP) is a theory developed by midwives, Jean Sutton and Pauline Scott. They found that the mother’s position and movement could influence the way her baby positioned itself in the final weeks of pregnancy.
This is believed to be a lifestyle issue as a result of society becoming more sedentary than we once were, with less physical labour on a day-to-day basis.
Sometimes longer, more painful labours and even caesareans result from, ‘mal-position’, where the baby’s position makes it more difficult for its head to move through the pelvis.
Why is Optimal Fetal Positioning good for my baby and me?
If your baby is coming head first and you have a single baby, (not multiple pregnancy) from about 34 weeks onwards follow this advice to encourage your baby to lie with its back to your left side/front. This can encourage your baby to engage, and lead to as straightforward a birth as possible for you.
During your antenatal check-ups, especially in the last 12 weeks, the doctor or midwife will palpate your abdomen to detect the baby’s position. While most mothers-to-be understand that head down is good, few understand the significance of a baby facing the mother’s naval or the mother’s spine.
Occipito-Anterior (OA) and Occipito-Posterior (OP), often called ‘Anterior’ and ‘Posterior’ for short, are the technical terms to describe the way your baby is positioned in the uterus. Both of these terms apply to a baby who is head down. The optimal position is Occipito-Anterior and this is the most effective way for a baby to journey through the maternal pelvis.
In the OA position, your baby is head down with his or her face looking at your spine. In the OP position, your baby is head down, facing your naval.
An OP baby and mother must do more work in order to have a vaginal birth. Labour is often longer and more painful, while the baby attempts to turn to the OA position. Commonly in OP labours, women experience back pain, caused by the hard surface of the baby’s skull pressing on the mother’s lower back.
How do I know what position my baby is in?
When the baby is ‘Anterior’, the back feels hard and smooth and rounded on one side of your tummy, and you will normally feel kicks under your ribs.
When the baby is ‘Posterior’, your tummy may look flatter and feel less firm, you may feel arms and legs towards the front and kicks on the front towards the middle of your tummy. The area around your belly button may dip in to a concave, saucer-like shape.
How can I help my baby move into the Anterior Position?
The baby’s back is the heaviest side of its body. This means that the back will naturally gravitate towards the lowest side of the mother’s abdomen. So if your tummy is lower than your back, e.g. if you are sitting on a chair leaning forward, then the baby’s back will tend to swing towards your tummy. If your back is lower than your tummy, e.g. if you are lying on your back or slouching on a sofa, then the baby’s back may swing towards your back.
Avoid positions which encourage your baby to face your tummy. The main culprits are said to be:
- Lolling back in armchairs
- Sitting in car seats where you are leaning back or anything where your knees are higher than your pelvis.
Tips to help baby move into the Anterior Position during pregnancy
The best way to avoid a posterior presentation is to spend lots of time kneeling upright, or sitting upright, or on your hands and knees.
- When you sit on a chair, make sure your knees are lower than your pelvis, and your trunk should be tilted slightly forwards.
- Regularly use upright and forward leaning postures. This allows more available space in the pelvis for your baby to turn.
- Sit with your knees lower than your hips, with your back as straight as possible.
- Use pillows or cushions under the bottom and small of the back to support your posture.
- Sit to read on a dining/kitchen chair with elbows resting on a dining/kitchen table, knees apart, leaning slightly forward (similar posture used when sitting on the toilet).
- Sit facing the back of a chair and resting your arms on the back of the chair. (This position may not be suitable for all women, eg, those with pelvic girdle pain).
- Kneel on the floor leaning over a large beanbag/ floor cushion to watch TV.
- When swimming use a variety of styles.
- When resting/sleeping, lie on your side, preferably left side with a pillow between the legs and back supported.
- Various exercises done on all fours can help, e.g. wiggling your hips from side to side, or arching your back like a cat, followed by levelling the spine.
Tips to help baby move into the Anterior Position when labour starts
It is ideal to use forward leaning postures when having Braxton Hicks (practice contractions) as this increases their effectiveness which aids helping the baby manoeuvre into the optimum position (OA). If possible stay on your feet leaning forward and rocking hips from side to side/up and down with each step, your bottom wiggling during contractions.
Alternate birthing positions
Standing helps with early labour
Standing and leaning forward helps relieve pressure on your back, as the baby doesn’t press on the spine. Swaying or rotating your hips at the same time can also ease the pain of contractions. Spending the first stage of labour upright is, for many women, the most effective way of handling contractions and speeding up labour. You can lean against a door, wall, your birth partner or over a kitchen worktop, whatever you find most comfortable.
Sitting is great when you’re tired
Many women prefer the sitting positions during early labour. Sit as upright as possible – gravity assists your baby’s head to press down on your cervix. Or, if you’re tired, lean forward onto a table while your birth partner massages your lower back through contractions.
Kneeling can help contractions
Kneeling and leaning forward onto a birthing ball is an excellent position for labour. Again, it can ease backache, and rolling backwards and forwards in a rhythmic movement can really help contractions
All fours is great for pushing
At the stage when you’re ready to push your baby out, a lot of women find it useful to have something hard to grip onto, be it a chair or the hospital bed. Kneeling is excellent as it still uses gravity and is easier on your legs than standing.
Squatting can speed things up
This is probably one of the most natural positions for women to labour in as you’ll feel in control and able to push effectively. It is well worth trying this position if progress in labour is slow, as it opens up the pelvis and increases the size of the birth canal. Your birthing partner can support you.
Squatting however is not the optimal position for when your baby’s head is crowning.
Alternate birthing positions & second stage care of perineum
There are a number of labour and birth positions. It is important to note that most of these positions can be used for both early labour and second stage active labour. While some are definitely not glamorous, they offer unique benefits to labour and birth.
Recent evidence from Scandinavia has shown that using manual perineal protection (MPP) can reduce severe trauma; a controlled, slow delivery of the head. Your midwife may advise you to adopt a position for delivery so she can see your perineum and use her hands to support your perineum.
The MPP is only given at crowning, so all the benefits of mobilising and staying upright in the second stage of labour still apply. Crowning takes place when the baby’s head remains visible without slipping back in as you are pushing.
You will be encouraged NOT to push when your baby’s head is crowning.
It will not be possible to use MPP when you are labouring in water.
Studies have also demonstrated that using warm compresses on the perineum during the second stage of labour reduces the risk of severe trauma – therefore you will be offered warm compresses during the second stage of labour.
Anal sphincter injury after vaginal delivery is not always immediately obvious and can occur even in presence of an intact perineum, therefore you will also be offered a rectal check following the delivery of your baby to ensure the integrity of your anal sphincter muscles. Before suturing you will be offered some local anaesthetic to numb the area prior to repair. After any suturing you will be offered suppositories to aid pain relief.
Some mothers may choose the all-fours position instinctively. It can help the baby turn around in the case of a mal-presentation of the head. Since this position uses gravity, it decreases back pain as the mother is able to tilt her hips.
Quadruped childbirth positions, which include the ‘crawl’ and the ‘full moon’, are beneficial for back labour, turning a posterior baby, and are often the best birth positions for birthing a large baby.
Although the sitting and semi-sitting birth positions may seem similar, they are very different. Sitting positions combine the helpful force of gravity with relaxation.
A birth ball, rocking, or toilet sitting can be utilized to rest while gravity helps labour progress.
Squatting positions may be helpful in opening the pelvis to allow a baby to find the optimal position for birth. Squatting can be performed through use of a birth companion.
The squatting position increases pressure in the pelvic cavity with minimal muscular effort. The birth canal will open 20%-30% more in a squat than in any other position.
However recent studies have demonstrated that a controlled, slow delivery of the head and use of manual perineal protection (MPP) reduces perineal trauma, therefore your midwife may advise you to adopt a position for delivery so she can see your perineum, use her hands to support your perineum and control the birth of your baby’s head.
Lateral or side-lying positions are beneficial for resting during a long labour, promoting body-wide relaxation, and minimizing extra muscular effort.
They are best used in the latter stages of labour since gravity isn’t able to speed the process. Side lying may help slow the baby’s descent down the birth canal, thereby giving the perineum more time to naturally stretch.
To assume this position, the mother lies on her side with her knees bent. To push, a slight rolling movement is used such that the mother is propped up on one elbow is needed, while one leg is held up.
Upright or standing positions
Upright positions for childbirth use gravity to the mother’s advantage. They help the baby drop into the pelvis and prevent pressure from being concentrated in a particular spot. They also allow the birth companions to apply other comfort measures easily.
As with squatting however, your midwife may encourage you to adopt a differing position for the second stage/crowning so she can visualise your perineum, use her hands to support your perineum and control the birth of your baby’s head.
Positions for not pushing
Occasionally, you may feel like pushing but your midwife may ask you not to push. This may happen if:
- your cervix is not fully dilated
- your cervix hasn’t opened up evenly leaving a ‘lip’ of cervix round your baby’s head
It can be very difficult not to push when nature is telling you to. You could try lying down on your left side or going into a knee-chest position (with your face on the floor and your bottom in the air) and panting through your contractions.
It’s not elegant, but it does tip your baby off your cervix and should reduce your desire to push. However, if you simply have to push, you’ll push, and your midwife will work with you.
Further information can be gained from contacting your community midwife or GP. You can also contact the Senior Midwife in the Fetal Maternity Assessment Unit.