Local anesthetic agent which is used for infiltration and nerve-blocking procedures included Epidural anesthesia. At latest update, published data concerning excretion into breast milk were not found. However, because its chemical structure is closely related to Bupivacaine, it is expected to occur in a non-significant level. There is controversy about the effect of drug-mediated analgesia used during the child birth (e.g. epidural injection of local anesthetics plus Fentanyl or alone) on the mature milk coming in, whether by delaying the onset of Lactogenesis phase II, or, by affecting the ability of the child for sucking. Some studies have shown a higher risk for delay of initiation of Lactogenesis phase II (milk coming in) longer than 3 post-natal days, but without effect on loss of initial weight. On other studies, the newborn infant appears to have higher risk for delay on first latch-on, higher body temperature and irritability or somnolence. Because of the latter, it is argued that those mothers would be in need of more support on breastfeeding when they have received ante or intra partum analgesia. However, other authors have failed to find the same results. There consensus on the achievement of higher milk production and higher body weight increase in the neonate with an adequate pharmacological control of pain after C-section or vaginal childbirth. Considering the fact that Mepivacaine readily crosses the placenta barrier, with a elimination-time period that is slower than adults (T ½ = 9 hours), it is safer the choice of Bupivacaine in case of prematurity or during the immediate neonatal period.