Reproductive success is critical for survival of the species. The timely onset of labor and delivery is an important determinant of perinatal outcome. Preterm birth (defined as delivery before 37 weeks’ gestation) and post-term pregnancy (defined as pregnancy continuing beyond 42 weeks) are both associated with a significant increase in perinatal morbidity and mortality. The factors responsible...

The initial signal for triggering human parturition might be fetal but of trophoblastic origin. Concomitantly, this placental signal would have as its target not only the uterus but also the fetus by activating its hypothalamo-pituitary-adrenocortical axis. The latter would represent a second fetal signal which, at the fetomaternal interface, would amplify and define in time the mechanisms resp...

In the United States, the annual rate of preterm births (before 37 weeks of gestation) reached a peak of 12.8% in 2006 and was 11.7% in 2011.1 The rate in the United States remains nearly twice the rate in European nations.2 Premature birth in the United States accounts for 35% of deaths in the first year of life3,4 and estimated annual costs exceeding $26 billion.5 Rates of death in the first ...

The last few hours of human pregnancy are characterized by uterine contractions that effect dilatation of the cervix and force the fetus through the birth canal. The myometrial contractions of labor are painful, which is why the term labor pains is used to describe this process. Before these forceful, painful contractions begin, however, the uterus must be prepared for labor. During the first 3...

The objectives of the present study were to compare the effects of a protracted and a conventional induction of parturition on the incidence of retained placenta, and to evaluate the suitability of transrectal Doppler sonography of the uterine arteries as a noninvasive method for the assessment of placental maturation. Protracted induction of labor (PIP) was precipitated in 13 cows by the admin...