Cord blood Acid-base status at delivery after successful external cephalic version.

摘要

Pregnancies after successful external cephalic version (ECV) are generally regarded as being normal. Nevertheless, increased levels of thyroid-stimulating hormone, an indicator of perinatal stress, recently were reported in cord blood in infants delivered vaginally after successful ECV. This retrospective study was an attempt to learn whether such infants are compromised, in particular, whether there are abnormalities of acid-base balance in cord blood. The 89 study cases were singleton deliveries at or after 37 weeks gestation that followed successful version. The same number of pregnancies with spontaneous cephalic presentation made up the control group. Women in the ECV group were significantly older, but there were no significant differences in birth weights or Apgar scores.Women in the ECV group had significantly more emergency cesarean deliveries than did control women. Cord blood arterial and venous acid-base parameters were similar in the 2 groups, as were the proportions of fetuses with a cordblood pH less than 7.20. Even after adjusting for maternal age, gestational age at delivery, mode of delivery, birth weight, spontaneous or induced labor, and duration of labor, differences in cord blood pH between the ECV and control groups were not significant.These findings support the use of ECV for term breech presentation. These infants may be more vulnerable biologically to the stress of labor, but with adequate intrapartum care, they should not be at increased risk of being acidotic at the time of birth. ECV may entail more emergency section deliveries, but it does lessen the incidence of cesarean deliveries for breech pregnancies.