ABSTRACT
OBJECTIVE: We measured levator ani neuromuscular function before and after first delivery to identify the location, timing, and mechanism of injury. STUDY DESIGN: Fifty-eight primiparous women underwent electromyographic examination of the levator ani antepartum at 6 weeks and 6 months after the delivery. Antepartum turns/amplitude data were pooled to create a normal range. We calculated each woman's percentage of outliers from this range and assessed relationships between delivery and extent of injury. RESULTS: At 6 weeks, 14 of 58 women (24.1%) had neuropathy, with 9 of those 14 women recovering by 6 months. At 6 months, 17 of 58 women (29.3%) were neuropathic, which included 12 new injuries. Women who had elective cesarean delivery had virtually no injury, but all other modes of delivery had similar injury rates. CONCLUSION: Obstetric delivery is associated frequently with electromyographic evidence of neuropathic injury to the levator ani. The entire levator complex is at risk, and cesarean delivery while in labor is not protective.
Subject(s)
Delivery, Obstetric/adverse effects , Neuromuscular Junction/injuries , Parity , Pelvic Floor/innervation , Adult , Cesarean Section/adverse effects , Delivery, Obstetric/statistics & numerical data , Electromyography , Female , Humans , Incidence , Labor, Obstetric , Pregnancy , Recovery of Function , Time Factors , Wounds and Injuries/diagnosis , Wounds and Injuries/epidemiology , Wounds and Injuries/etiology , Wounds and Injuries/physiopathologyABSTRACT
Utilizing the bicistronic reporter transposon mini-Tn5 lacZ-tet/1, we have identified lacZ fusions to four Escherichia coli genes/operons that are strongly activated by the accumulation of self-produced extracellular signals. These fusions were designated cma9, cma48, cma113, and cma114 for conditioned medium activated. Each of the cma fusions was expressed in a growth phase-dependent manner, and the presence of conditioned medium from a stationary phase E. coli culture resulted in the premature activation of these fusions in cells at early to mid-logarithmic phase. The cma48 and cma114 fusions were dependent on RpoS for growth phase expression and response to extracellular factors. The extracellular factors that activated the cma9, cma48, and cma114 fusions were produced in both rich complex and defined minimal media. The cma fusions were shown to be within the cysK (cma9), astD (cma48), tnaB (cma113), and gabT (cma114) genes. These genes function in the uptake, synthesis, or degradation of amino acids that yield pyruvate and succinate.