Abnormal Pregnancies

“Normal” Presentation

The majority (90%) of pregnancies are cephalic (either occiput anterior or occiput transverse).

Breech Presentation

Most are delivered by Cesarean section. Su et al. studied 2088 women from 121 hospitals in 26 countries (the Term Breech Trial) and showed that the relative risk for an adverse outcome of an elective Cesarean section is 0.14 (p < 0.001) at labor and 0.37 (p = 0.03) during delivery as compared to planned vaginal births [Su et al. BJOG 111: 1065, 2004]. General anesthesia may be desirable for a breech Cesarean section as extraction may be difficult with regional alone – 50-200 ucg of IV nitroglycerine or 400 ucg SL nitroglycerin can be attempted, but sometimes the relaxing effects of a volatile anesthetic are necessary. If a vaginal delivery is to be attempted, an epidural will allow the patient to bear down with low-dose anesthetics (ex. 0.125% bupivacaine) during the first stage of labor, then provide enhanced analgesia during the second stage (ex. 2% lidocaine).

Multiple Gestation

Considerations should include 1) frequent need for emergent C-section of second child 2) frequency of breech presentation and 3) frequency of prematurity. Triplets and greater are always delivered by Cesarean section.