Correlation of Change in Uterine Activity to Blood Loss in theThird Stage of Labour

Abstract

In 47 women, the change in the uterine activity after the administration of a uterotonic agent was correlated with the amount of blood loss during the same period of time. Uterine activity was measured by a Gaeltec^® catheter-tipped pressure transducer inserted transcervically within 5 min of delivery of the placenta. A uterotonic agent (either intravenous syntocinon, intramuscular syntometrine or oral misoprostol) was given after the insertion of the intrauterine pressure catheter and pressure recorded for another 90 min. Blood loss over the same 2-hour period was collected with absorbent paper which was then assessed by colorimetric measurement of the haemoglobin content in the sample. Our results show that the change in uterine activity is associated with the total blood loss. However, there is a poor linear correlation between the two variables probably because of the biological variation in myometrial activity and differences in coagulation mechanisms in normal women.

Condom Tamponade in the Management of Massive Obstetric Hemorrhage: An Experience at a Teaching Hospital

“…The mechanical constriction of the blood vessels due to the uterine muscle contraction and retraction and by clots sealing off the raw surface in the placental bed usually stops uterine bleeding at the site of placental separation. 18 Uterine contractions are promoted by the pituitary hormone oxytocin, whose release is stimulated by the stretching of the cervix and vaginal canal during birth and by nipple stimulation during lactation. 19 Coagulation factors in the maternal blood contribute to the formation of clots that also stem the blood flow.…”

Management of the Third Stage Of Labor: An Evidence‐Based Approach

“…The research team hypothesized the inconsistency was the result of biologic variations. Using the same catheter‐tipped pressure transducer method, Choo et al (8) studied a small group of 47 women and found that increased uterine activity immediately after placental expulsion tended to correlate with a decrease in total blood loss; however, they recognized the limits of the small study and recommended larger studies to explore the strength of relationship as well as other potential influences that could impact the results. In general, these studies supported conventional wisdom that early uterine activity with early expulsion of the placenta tended to result in less overall blood loss.…”

Uterine Activity During the Third Stage of Labor

“…Other studies have used IUPCs following the expulsion of the placenta 7–10 . No cases were described in these studies that did not record contractions.…”

“…No cases were described in these studies that did not record contractions. The description of the insertion was the same as in this study 7–10 . The uterine activity was reported in a summative manner rather than providing contraction frequency and intensity, because sometimes uterine contractions following placental expulsion would be tetanic or hypertonic, such that return of the contraction curve to the baseline took several minutes 10 .…”