Influence of time at which oxytocin is administered during labor on uterine activity and perinatal death in pigs

Abstract

Oxytocin is extensively used to induce or augment uterine contractions, especially to facilitate the third stage of labor in humans. Administration of oxytocin to parturient sows reduces duration of labor whereas mortality of the offspring may remain unchanged. This study aimed to evaluate whether time of administration of oxytocin during parturition may alter the uterine response and fetal outcomes. Two hundred parturient sows were randomly assigned to intramuscularly receive either saline solution (control group) or oxytocin 0.083 IU/kg immediately after the delivery of the 1 st , 4 th or 8 th piglet (groups O-1, O-4 and O-8, respectively). Uterine effects and fetal outcomes were registered in all groups. The duration of labor was 20-40 min shorter (P < 0.0001) and time interval between babies was reduced by 3-5 min (P < 0.0001) in the three groups receiving oxytocin. The duration and intensity of contractions, meconium-stained piglets and intrapartum deaths decreased as time at which oxytocin administered during labor was increased. In group O-8, we observed approximately 70% less meconium-stained piglets and intrapartum deaths than in the control group. In conclusion, oxytocin administered at early phases of parturition to sows may increase duration and intensity of uterine contractions as well as adverse fetal outcomes.

Uterine activity and fetal electronic monitoring in parturient sows treated with vetrabutin chlorhydrate

“…In humans, values of uterine activity during the birthing process have already been identified, and oscillate between 90 and 250 MU (Caldeyro-Barcia et al, 1957). Veterinary obstetrics started working on monitoring myometric activity in the 1970s on mares, and today there is recent work reporting on intrauterine pressure and myometric contraction duration in sows with different parities, housing conditions, and treatments at the moment of the birthing, including the administration of oxytocin (Mota-Rojas et al, 2005a, 2007aOlmos-Hernández et al, 2008).…”

“…The uterotonic drugs frequently used to diminish mortality at birth effectively reduce the length of the piglet birth process (Straw et al, 2000;Mota-Rojas et al, 2005a,c). However, at times it increases the intensity and frequency of contractions in the uterus, which in turn damages the UC (Linneen et al, 2005), causes greater fetal mortality (Alonso-Spilsbury et al, 2004;Mota-Rojas et al, 2006), and diminishes vitality (Mota-Rojas et al, 2007a). Any increase in the tension of the UC during the birth process causes circulatory alterations in the UC; this increases the risk of anoxia at the time of birth and leads to a high rate of perinatal death (Randall, 1972).…”

Predictive factors for perinatal death in nuchal cord cases: a case control study

“…Even though a similar finding has not been reported in the available literature, oxytocin infusion is a welldocumented risk factor for birth asphyxia and perinatal death. 14,15 The decision to augment labor in the presence of nuchal cord therefore increases the risk of birth asphyxia and subsequent fetal death.…”

Tools and Protocols for Managing Hyperprolific Sows at Parturition: Optimizing Piglet Survival and Sows’ Reproductive Health

“…This applies also to sows that are restless and have strong abdominal contractions during parturition Table 3. Guidelines for diagnosis and treatment of birth complications [12,[61][62][63][64][65][66][67][68][69]. Table 4.…”