Is there an association between sonographically determined occipito-transverse position in the second stage of labor and operative delivery?

OBJECTIVE

To evaluate if ultrasound-determined occipito-transverse position early in the second stage of labor is associated with operative delivery.

DESIGN

Retrospective review of two prospective cohort studies.

SETTING

An Australian tertiary referral hospital.

POPULATION: Women with term, cephalic singleton pregnancies.

METHODS

Retrospective analysis of data from two prospective studies. Logistic regression was undertaken to assess the independent contribution of the occipito-transverse position to operative delivery.

MAIN OUTCOME MEASURE: Operative delivery (cesarean section, forceps or vacuum extraction).

RESULTS

Among 422 women included, the occipito-transverse position was present in 80, occipito-anterior in 303 and the occipito-posterior in 39. Compared with occipito-anterior, the adjusted odds ratio for operative delivery was 2.1 (95% confidence interval 1.2-3.8, p = 0.02) for the occipito-transverse position, and 7.4 (95% confidence interval 3.2-17) for the occipito-posterior position. Factors that independently predicted operative delivery were nulliparity, abnormal second stage cardiotocography, maternal place of birth and epidural analgesia. The length of second stage of labor was longer for the occipito-transverse group than for the occipito-anterior group (median 2 h 7 min vs. 1 h 36 min, p = 0.003).

CONCLUSION

The occipito-transverse position early in the second stage of labor was associated with an increased operative delivery rate.