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PubMed2002

Management of vaginal birth after cesarean.

OBJECTIVE: To raise the success rate of vaginal birth after cesarean (VBAC) without increasing maternal or perinatal morbidity and mortality rates. METHODS: Of 468 women with a prior scar, 365 gave valid informed consent for our management of VBAC at Akashi Municipal Hospital during 1986-1999. Trials of labor (TOL) were attempted in 322 cases principally by waiting for spontaneous labor onset and teaching the patients a breathing method to avoid straining until expulsion by vacuum extraction become possible, controlling the intrauterine pressure. Our selection criteria for TOL changed during the trial; from 1991-1999 patients with a prior scar extending into fundus were excluded. RESULTS: Of the 322 TOL, 88.2% were successful, and VBAC was successful in 77.8% (284 of the 365 patients). Uterine rupture was observed in 2 cases (0.62%). Fetal death occurred in 1 case. Three women gave birth to neonates with a 1-minute Apgar score < or = 6. CONCLUSION: The rate of VBAC was 77.8% in all women with a prior scar. During our management of VBAC, maternal or perinatal morbidity and mortality rates did not increase significantly.

Adult↗
PubMed1990

Steroid sulfohydrolase in human chorion and decidua: studies using pregnenolone sulfate and dehydroepiandrosterone sulfate as substrate.

Human chorion and decidua use pregnenolone sulfate (P5S) and dehydroepiandrosterone sulfate (DHAS) as substrates for local estrogen and progesterone synthesis. We hypothesized that the local estrogen/progesterone ratio may influence contractility of the adjacent myometrium and hence effect the timing of parturition. Thus, we studied steroid sulfohydrolase activity for P5S in these tissues and investigated the potential interaction of other steroids on the rates of hydrolysis of P5S and DHAS. The enzyme was present in both tissues, predominantly in the microsomal fraction. With P5S as substrate, the Michaelis-Menten constant (Km) was similar in chorion (1.3 +/- 0.2 mumol/L, mean +/- SEM) and decidua (0.9 +/- 0.1 mumol/L) but the maximum velocity (Vmax) was significantly greater in chorion (2.6 +/- 0.4 vs. 1.1 +/- 0.3 nmol/mg protein/15 min, P less than 0.05). In both tissues there was a tendency towards greater activity in tissues obtained before labor compared to tissues obtained after spontaneous labor onset. Using either DHAS or P5S as substrate, there was significant inhibition of sulfohydrolase activity by other steroids at concentrations similar to those in late pregnancy fetal and maternal plasma. In microsomal preparations using DHAS as substrate, activity was inhibited by equimolar concentrations of estrone sulfate (E1S, by 38 +/- 2%), P5S (by 74 +/- 2%), and cholesterol sulfate (C27S, by 38 +/- 3%). With P5S as substrate, equimolar concentrations of E1S, DHAS, and C27S caused inhibition of sulfohydrolase activity by 19 +/- 5%, 16 +/- 4%, and 18 +/- 2%, respectively. These inhibitory effects also were observed using a tissue explant system with intact cells. In kinetic inhibition studies using DHAS as substrate, E1S and P5S were competitive inhibitors with inhibition constants (Ki) of 4.8 +/- 1.3 and 0.7 +/- 0.1 mumol/L, respectively. Using P5S as substrate, E1S and DHAS also were competitive inhibitors with Ki values of 8.2 +/- 2.1 and 9.6 +/- 1.2 mumol/L, respectively. For both substrates, the pattern of inhibition by C27S was complex. Preliminary experiments to distinguish, on the basis of differing physical-chemical properties, separate enzymes for different substrates were inconclusive. We conclude that human chorion and decidua can hydrolyze several steroid sulfoconjugates and this activity may regulate local estrogen and progesterone synthesis. There are significant interactions among steroid sulfoconjugates in regulating this activity. These activities may be important components of a paracrine system that determines myometrial contractility and the timing of parturition.

Arylsulfatases↗
PubMed2006

Prediction of labor and delivery by transperineal ultrasound in pregnancies with prelabor rupture of membranes at term.

OBJECTIVE: To evaluate whether engagement of the fetal head or cervical length in women with premature rupture of membranes (PROM) at term, are associated with time from PROM to delivery or need for operative delivery. METHODS: A transperineal ultrasound examination was performed in 152 women with a single live fetus in cephalic presentation after PROM (at > 37 gestational weeks). The shortest distance from the outer bony limit of the fetal skull to the skin surface of the perineum was measured in a transverse view, and the cervical length was measured in a sagittal view. The time from PROM to delivery was tested in a Cox regression analysis with ultrasound measurements, parity, maternal age, body mass index and birth weight as possible predictive factors. RESULTS: The head-perineal distance was associated with the time from PROM to delivery (log rank test, P < 0.001). Thirty-six hours after PROM, 32% (95% CI, 15-49) of women with a short head-perineal distance (< 45 mm) and 43% (95% CI, 24-62) of women with a long distance (> or = 45 mm) were still in labor. Women with a short head-perineal distance had fewer Cesarean sections, less use of epidural analgesia and a shorter time in active labor, and their babies had a higher pH in the umbilical artery. The measured cervical length was not associated independently with time to delivery. CONCLUSION: Transperineal ultrasound measurements of fetal head engagement may help clinicians to predict the course of labor in women with PROM.

Cervix Uteri↗
PubMed1993

Identification and partial characterization of phospholipase D in the human amniotic membrane.

The enzymatic activity of phospholipase D and its characteristics have been examined in human amnion tissue. The phospholipase D activity was not Ca(2+)- or Mg(2+)-dependent and was activated by unsaturated fatty acids. The optimal pH of phospholipase D was 5.5. The phospholipase D activity in amnion tissue was highest in the microsomal fraction, and preferentially utilized phosphatidylcholine as a substrate. The phospholipase D activity of the microsomal fraction of amnion tissue obtained at term before labor onset (34.0 +/- 16.3 nmol/hour/mg protein, mean +/- SD, n = 11) was significantly (p < 0.05) higher than the activity in this tissue obtained from women in the mid-trimester (15.0 +/- 7.5 nmol/hour/mg protein, n = 9).

Amnion↗
PubMed2000

Cytokines and placental macrophages in regulation of birth activity.

The article reviews present notions on functional activity of cytokines of the fetoplacental complex. Particular emphasis is placed on the role of these molecules in the regulation of gestation processes and in pregnancy incompetence. The mechanism of the involvement of placental macrophages and their products in gestation and delivery is discussed.

Cytokines↗
PubMed2006

Characterization of abdominally acquired uterine electrical signals in humans, using a non-linear analytic method.

The present work seeks to determine if a particular non-linear analytic method is effective at quantifying uterine electromyography (EMG) data for estimating the onset of labor. Twenty-seven patients were included, and their uterine EMG was recorded non-invasively for 30 min. The patients were grouped into two sets: G1: labor, N = 14; G2: antepartum, N = 13. G1 patients all delivered spontaneously within 24 h of recording while G2 patients did not. The uterine electrical signals were analyzed offline by first isolating the uterine-specific frequency range and then randomly selecting "bursts" of uterine electrical activity (each associated with a uterine contraction) from every recording. Wavelet transform was subsequently applied to each of the bursts' traces, and then the fractal dimension (FD) of the resulting transformed EMG burst-trace was calculated (Benoit 1.3, Trusoft). Average burst FD was found for each patient. FD means for G1 and G2 were calculated and compared using t test. FD was significantly higher (P < 0.05) for G1: 1.27 +/- 0.03 versus G2: 1.25 +/- 0.02. The wavelet-decomposition-generated fractal dimension can be used to successfully discern between patients who will deliver spontaneously within 24 h and those who will not, and can be useful for the objective classification of antepartum versus labor patients.

Abdomen↗
PubMed1984

The use of breast stimulation to prevent postdate pregnancy.

Postdate pregnancy is estimated to occur in 3% to 12% of all gestations. Morbidity and mortality rates associated with this common obstetric problem are higher than those with term gestation. The incidence of fetal distress, birth injury, meconium aspiration, congenital malformations, macrosomia, and oligohydramnios is also greater in postdate pregnancy. We prospectively evaluated breast self-stimulation to determine its effect on the incidence of postdate pregnancy. Two hundred low-risk patients at 39 weeks' gestation were randomly assigned to either a control group or a breast-stimulation group. Results showed that breast stimulation reduced the number of pregnancies managed as postdates from 17 per 100 (17%) to five per 100 (5%) (p less than 0.01), a 70% reduction. It is concluded that breast stimulation in postdates pregnancies can decrease significantly the number of patients that must be monitored by biochemical or biophysical means.

Adult↗
PubMed1985

Inhibition of fetal membrane prostaglandin production by prolactin: relative importance in the initiation of labor.

Production of a biologically active prolactin by human decidual tissue and its influence on the permeability of amniochorion to water suggests a functional relationship between the polypeptide and fetal membrane metabolism. Under in vitro circumstances, we used ovine prolactin and the Ussing chamber technique to determine the role of prolactin in prostaglandin E2 production by human fetal membrane. Fresh reflected membranes obtained from elective cesarean sections were exposed to ovine prolactin (10 micrograms/ml). Aliquots of incubation media were sampled at 0, 30, 60, 120, and 240 minutes, quick-frozen, and later assayed for prostaglandin E2. Multifactorial analysis of variance revealed that ovine prolactin significantly reduced prostaglandin E2 production (f = 13.42, p less than 0.005). Prostaglandin E2 output was greatest by amnion (3581 +/- 596 pg/ml/gm declining to 1819 +/- 452 pg/ml/gm during 4 hours). Other combinations of fetal membranes including amnion-chorion-decidua produced only 12% to 15% prostaglandin E2 per gram compared with that produced by amnion alone. Those membranes similarly responded to prolactin with a reduction in prostaglandin E2 output of 34% to 59%. Correlation analysis identified a significant relationship between prostaglandin E2 production and time (r = 0.298; p less than 0.001), which was abolished by ovine prolactin (r = 0.115, p greater than 0.10). This model illustrates that ovine prolactin modifies the production of prostaglandin by fetal membranes in vitro. By analogy, endogenous prolactin by human decidual tissue might also inhibit the elaboration of prostaglandin E2 from its precursors residing within the fetal membranes.

Amnion↗
PubMed1989

Late maternal age and postdate pregnancy.

Charts of 443 postdate pregnancies were reviewed to determine the effect of late maternal age on pregnancy outcome. There were significantly more low 1-minute Apgar scores, intrapartum decelerations, and cesarean sections in the group of women greater than 35 years old. Use of oxytocin percentages and the results were similar with regard to both groups. Five-minute Apgar scores also were similar. Women greater than 35 years of age are less able to be delivered of postdate infants with optimal outcomes, but it is still safe to allow them to exceed 42 weeks' gestation.

Adult↗
PubMed1991

Maturation of the uterine cervix by repeated intracervical instillation of prostaglandin E2.

An attempt was made to ripen the uterine cervix in 100 high-risk pregnancy patients (pregnancy between 34 to 41 weeks' gestation), with the use of intracervical instillations of 0.25 mg of prostaglandin E2 mixed with a tylose gel. The maturation process was repeated every 48 hours. Forty-nine patients were delivered of infants after the first maturation and 51 patients required between two and nine instillations. In patients requiring multiple instillations, the mean delay between the first procedure and delivery was 9 +/- 4 days (range, 2.4 to 16 days). Among the 59 nulliparous women, only 23 were delivered of infants after a single maturation and 36 required multiple maturations (p less than 0.02). When the group of patients who were delivered of infants after a single maturation process was compared with the group requiring multiple maturations, no difference could be seen with regard to age, term of pregnancy, or Bishop cervical score at the time of inclusion in the study. The myometrial activity and the onset labor induced by prostaglandin E2, were similar in both groups. Fetal heart rate decelerations occurred in 16.3% (8/49) of the patients with single maturations and in 17.6% (9/51) of the patients who required multiple maturations. The outcome of the pregnancy and the rate of cesarean sections (24% and 27%) were similar in both groups. No patients required cesarean sections because of failed induction of labor. Cervical ripening after repeated applications of 0.25 mg of prostaglandin E2 seems to be safe for the fetus, providing that the patient is closely supervised.

Cervix Uteri↗