The uterine tissue consists of unstriped muscle fibre and ganglia of the sympathetic system imbedded in it. The sacral roots and pelvic nerve do not enter into the composition of the uterine plexus. In the rabbit, irritation of the hypogastric nerve produces vasoconstriction and contraction of the uterus. In cats, stimulation of the hypogastric nerve produces at one time contraction and at othe...

Parturition is composed of five separate but integrated physiological events: fetal membrane rupture, cervical dilatation, myometrial contractility, placental separation and uterine involution. Prostaglandins (PGs) have central roles in each of these, but the most studied is myometrial contraction. Elevated uterine PGs or the enhanced sensitivity of the myometrium to PGs leads to contractions a...

This paper describes the use of the Morlet wavelet transform to investigate the difference in the time-frequency plane between uterine EMG signals recorded simultaneously on two different sites on women’s abdomen, both during pregnancy and in labor. The methods used are wavelet transform, cross wavelet transform, phase/amplitude correlation, and phase synchronization. We computed the linear rel...

That a physiologically active substance could be obtained from the pituitary body was first discovered by Oliver and Schafer1 in 1895. Some time afterwards (in 1906) Dale found that an extract of the posterior lobe could produce uterine contractions. This discovery was confirmed by Blair Bell3 in 1909; by experimental observations on rabbits he found that it caused powerful uterine contractions...

OBJECTIVE The diagnosis of labor is currently one of the most difficult problems encountered by obstetrical healthcare providers. A major health problem is the increase in the rate of preterm delivery, which is responsible for 75% of all deaths in newborns. In addition, preterm delivery is associated with several cognitive and health problems in later life and enormous costs for the health syst...

Abortifacients of vegetable origin are commonly used in rural areas for termination of pregnancy and inducing uterine contractions during postpartum period. Preliminary studies on five plants which are the ingredients of a commonly used herbal decoction, Dashmool, have alreadybeen reported from this laboratory (3 and 1). The present work embodies detailed observations on the pharmacological act...

Little is known about the adaptation of uterine artery smooth muscle contractile mechanisms to pregnancy. The present study tested the hypothesis that pregnancy differentially regulates thick- and thin-filament regulatory pathways in uterine arteries. Isometric tension, intracellular free Ca(2+) concentration, and phosphorylation of 20-kDa myosin light chain (MLC(20)) were measured simultaneous...

Preterm birth is associated with the majority of all death and chronic disability related to pregnancy, birth and the neonatal period. The costs to families and to the health care system are enormous. Current approaches to prevent or arrest preterm labour have been unsuccessful. This failure is largely based on our poor understanding of the regulation of the timing and maintenance of parturitio...