Obstetrics and gynecology
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Obstetrics and gynecology · Jul 1991
Effect of maternal carbon dioxide inhalation on human fetal breathing movements in term and preterm labor.
Induced maternal hypercapnia is a potent stimulus to fetal breathing movements in nonlaboring pregnant women. To determine the effect of maternal CO2 administration on fetal breathing movements during spontaneous labor, 14 healthy pregnant volunteers at term and 34 in preterm labor were recruited. ⋯ Among women with suspected preterm labor, initial absence of fetal breathing movements and failure to evoke this response by maternal hypercapnia predicted delivery within 48 hours with a sensitivity of 80% and specificity of 95.5%. Induced maternal hypercapnia fails to stimulate fetal breathing movements in true term and preterm labor and may assist in distinguishing between true and false preterm labor.
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Obstetrics and gynecology · Jul 1991
Changes in calcium homeostasis over the first year postpartum: effect of lactation and weaning.
There is little information on the effect of lactation on maternal mineral and calcitropic hormone status. Therefore, we prospectively compared 26 lactating women with 32 nonlactating postpartum controls over the first year postpartum. Nineteen of the 26 women breast-fed their infants for fewer than 12 months and seven breast-fed for at least 12 months. ⋯ At 12 months, women who were weaning had significantly higher mean serum calcium (10.11 mg/dL) and magnesium (2.36 mg/dL) concentrations than those who had weaned (8.79 and 2.03 mg/dL, respectively) or who had never lactated (8.90 and 1.95 mg/dL, respectively). Serum phosphorus, PTH, and 1,25-dihydroxyvitamin D were similar among women who were weaning (4.02 mg/dL, 1.46 ng/mL, and 54 pg/mL, respectively) and those who had weaned (3.94 mg/dL, 1.68 ng/mL, and 55 pg/mL), and were significantly higher than concentrations in women who had never lactated (3.25 mg/dL, 0.92 ng/mL, and 39 pg/mL). Our findings during lactation and the persistent differences observed during and after weaning are consistent with bone mobilization during lactation and a recovery of bone mass during and after weaning.
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Obstetrics and gynecology · May 1991
Randomized Controlled Trial Comparative Study Clinical TrialLabor induction with continuous low-dose oxytocin infusion: a randomized trial.
One hundred twenty-three women were randomized to receive either of two regimens of oxytocin for labor induction. Sixty-one received a low-dose regimen, with oxytocin increases at intervals of not less than 60 minutes. Patients with unripe cervices received prolonged low-dose oxytocin priming before membrane rupture. ⋯ Cesarean delivery and cesareans for fetal distress were more frequent in the traditional protocol group. This study demonstrates that a continuous low-dose protocol for oxytocin induction of labor is effective in establishing active labor and achieving vaginal delivery in women with both ripe and unripe cervices. It is also associated with fewer episodes of uterine hyperstimulation requiring adjustments of oxytocin infusion than is the traditional protocol of this institution.
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Obstetrics and gynecology · Apr 1991
Indwelling epidural catheters for pain control in gynecologic cancer patients.
Seven patients with severe pain caused by an advanced, incurable gynecologic malignancy were treated with an indwelling epidural catheter connected to an implantable subcutaneous port through which morphine was infused. There were few major complications associated with insertion or maintenance of the system. The average usage was 60 days, although the system functioned continuously for 6 months in one patient. ⋯ All patients, including one with liver metastases, reported good to excellent pain control with the epidural narcotics. Two subjects with upper abdominal pain occasionally required supplemental oral oxycodone, but the other five patients had adequate pain relief with the epidural system alone. The indwelling epidural system provides excellent analgesia for patients with advanced, incurable gynecologic cancer.
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Obstetrics and gynecology · Apr 1991
Peripheral arterial vasodilation hypothesis of sodium and water retention in pregnancy: implications for pathogenesis of preeclampsia-eclampsia.
Primary peripheral arterial vasodilation with relative underfilling of the arterial circulation occurs in early pregnancy and leads to several consequences, including decreased systolic and diastolic blood pressures, enhanced cardiac output secondary to afterload reduction, stimulation of the renin-angiotensin-aldosterone axis, nonosmotic stimulation of thirst and vasopressin release, and renal sodium and water retention with expansion of the extracellular fluid and plasma volume compartments. These are events known to occur in all states of arterial vasodilation. Pregnancy has, however, several unique features. ⋯ The increased glomerular filtration rate and filtered sodium load with enhanced distal tubular sodium delivery allows escape from aldosterone, an effect not observed in other states of arterial underfilling. This vasodilator may also account, at least in part, for the vascular resistance to angiotensin known to occur in normal pregnancy. This hypothesis for the normal physiology of pregnancy sets the stage for understanding the pathogenesis of preeclampsia-eclampsia.(ABSTRACT TRUNCATED AT 250 WORDS)