What is the antepartum management of a fetus in the occipital posterior (OP) position?

From the Guidelines

The most effective antepartum management of a fetus in the occipital posterior (OP) position involves encouraging fetal rotation to a more favorable position before labor begins, primarily through maternal positioning exercises such as hands-and-knees positions for 10 minutes several times daily, starting at 34-36 weeks gestation. These exercises are based on the principle of utilizing gravity and pelvic biomechanics to encourage the fetus to rotate from a posterior to an anterior position, which can reduce the risk of complications during labor, such as prolonged labor, increased need for interventions, and potential fetal distress 1. Key exercises include:

• The knee-chest position
• Pelvic tilts
• Swimming with forward strokes
• Sitting on a birth ball with wide-spread knees while leaning slightly forward
• Using side-lying positions with the affected side down (the side where the fetal back is located) It is also recommended that women avoid reclining positions that tilt the pelvis backward, as these may reinforce the posterior position 1. Additionally, complementary approaches such as chiropractic care using the Webster technique, acupuncture, and moxibustion may be considered, although the evidence for these methods is less robust compared to maternal positioning exercises 1. Regular prenatal visits are crucial to monitor fetal position, and if the posterior position persists near term, consideration of external cephalic version may be necessary, although this is more commonly used for breech presentations 1. It's worth noting that approximately 90% of fetuses in posterior position will spontaneously rotate during labor, making these preventative measures important but not mandatory 1.

From the Research

Antepartum Management of Occipital Posterior (OP) Position

The antepartum management of a fetus in the occipital posterior (OP) position involves several strategies to prevent and correct the position. Some of the key aspects of antepartum management include:

• Prenatal maneuvers to rotate the OP fetus to occiput anterior, although the evidence for this is limited 2
• Maternal positions to facilitate rotation of the OP fetus, with some studies suggesting that lateral position on the same side of the fetal spine is effective 3
• The use of ultrasound examination to identify fetal position, which is a reliable method for detecting OP position 2, 4

Maternal Positions and Fetal Rotation

Maternal positions can play a crucial role in facilitating fetal rotation. Some of the key findings on maternal positions and fetal rotation include:

• Maternal postural techniques can promote the anterior position of the fetal head for delivery 4
• Lateral position on the same side of the fetal spine has been shown to be effective in reducing persistent OP positions 3
• Maternal positions can reduce back pain and improve fetal rotation, although the evidence for this is limited 2, 4

Manual Rotation and Instrumental Delivery

Manual rotation and instrumental delivery are also important aspects of antepartum management of OP position. Some of the key findings on manual rotation and instrumental delivery include:

• Manual rotation can be performed by midwives and may reduce cesarean sections and instrumental births 5, 6
• Obstetrical forceps seem more efficient than vacuum in achieving fetal head rotation, but are associated with severe perineal tears 3
• Manual rotation is considered acceptable by most midwives, yet is only performed by a minority, suggesting a scope to introduce this procedure into widespread clinical practice 6