What are the complications of Occipito posterior position?

Occiput posterior (OP) positions account for 15 to 20% of cephalic presentations at the onset of labor [1], [2], [3], [4]. Although spontaneous rotation in occiput anterior (OA) position occurs in most cases, the OP position persists at delivery in nearly 10% and is associated with obstetric complications, including prolonged labor, cesarean delivery, operative vaginal delivery, third- and fourth-degree perineal tears or lacerations, postpartum hemorrhage (PPH) and chorioamnionitis [5], [6], [7], [8], [9], [10], [11], [12]. The causation of posterior positions is multifactorial and observational studies report the following risk factors for their persistence at delivery: nulliparity, obesity, high maternal age, maternal sub-Saharan African origin, prolonged pregnancy, macrosomia, anterior placenta and epidural analgesia [1], [5], [13], [14], [15].

Nonetheless, the effectiveness of obstetric management strategies promoting the rotation of posterior positions, especially during the first stage of labor, remains to be demonstrated. Manual rotation is an effective method for turning the fetal head [16], but it is successful more often during the second stage of labor [17] and can sometimes cause fetal heart rate abnormalities, cervicovaginal injuries and in rare cases cord prolapse [18]. Another strategy uses maternal postures, such as hands-and-knees, lateral decubitus adapted to fetal station or lateral asymmetric decubitus. These are less iatrogenic and may promote earlier rotation, but randomized trials have not provided evidence of their effectiveness in promoting rotation of OP positions [19], [20], [21], [22]. Finally, other medical practices, such as analgesia, artificial rupture of membranes, or oxytocin infusion, are common during the first stage of labor, but studies that assess their effects on OP positions are lacking.

A better understanding of the factors affecting rotation of OP positions during the first stage of labor may help to promote earlier rotation and reduce obstetric complications associated with persistent OP positions. Accordingly, our principal objective was to identify maternal, neonatal and obstetric factors associated with rotation from OP to OA position during the first stage of labor. The secondary objective was to compare obstetric and neonatal outcomes associated with anterior rotation during this stage.

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• Management of persistent occiput posterior position: The added value of manual rotation

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• Simple Models to Predict Vaginal Delivery and Spontaneous Fetal Occiput Rotation Based on Intrapartum Ultrasound and Maternal Characteristics

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• The Pathophysiology of Labor Dystocia: Theme with Variations

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  What is the outcome of Occipito posterior position?

  Occiput posterior (OP) position is the most common fetal malposition. It is important because it is associated with labor abnormalities that may lead to adverse maternal and neonatal consequences, particularly operative vaginal or cesarean birth.

  What increases the risk of persistent Occipito posterior position?

  Conclusion: Epidural use, AROM, African-American ethnicity, nulliparity, and birth weight >4000 g are associated with persistent OP position at delivery, with higher rates of operative deliveries and obstetric complications.

  How is labor affected when the fetus is in an occiput posterior OP position?

  The posterior position at birth is associated with a higher risk of short-term complications for the baby, such as lower five-minute Apgar scores, a greater likelihood of needing to be admitted to the neonatal intensive care unit (NICU), and a longer hospital stay.

  What are the causes of Occipito posterior position?

  The occipitoposterior position in the main is caused by the adaptation of the head to a pelvis having a narrow fore pelvis and an ample anteroposterior diameter and therefore may be considered “physiologic.”