Lawrence Nathan
University of Texas Southwestern Medical Center
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Obstetrics & Gynecology | 1994
Robyn Horsager; Lawrence Nathan; Kenneth J. Leveno
Objective: To compare the measured volume of amniotic fluid (AF) in term gestations to the volume predicted sonographically. Methods: One hour before elective cesarean delivery, 40 women had sonographic measurement of the AF index and largest vertical pocket diameter. At surgery, a suction catheter was placed into a 1‐cm uterine incision and a second catheter was used to aspirate AF from the operative field. Hemoglobin concentration was measured in the collected AF to determine the extent of blood contamination. Results: The mean measured AF volume was 532 mL (range 40‐1692). The correlation cofficient between AF index and AF volume was 0.744 (P < .001). A similar value (r = 0.755, P < .001) was observed for the largest vertical pocket measured with ultrasound. Conclusion: Sonographic measurements of the largest vertical pocket and the AF index have similar positive correlations with measured AF volumes at term. Current methods of estimating AF volume have low sensitivity for detecting oligohydramnios. (Obstet Gynecol 1994;83: 955‐8)
American Journal of Obstetrics and Gynecology | 1993
Lawrence Nathan; Mark T. Peters; Annelle M. Ahmed; Kenneth J. Leveno
A dramatic decline in the prevalence of serious puerperal infection caused by group A beta-hemolytic streptococci has been observed throughout most of the twentieth century, and it is currently a very uncommon cause of maternal morbidity and mortality. We report on two term pregnancies complicated by profound multisystem organ failure caused by group A streptococcal puerperal sepsis. This report serves to highlight the apparent return of serious group A streptococcal puerperal sepsis and to emphasize the clinical implications and sequelae attributable to an old yet virulent enemy.
American Journal of Obstetrics and Gynecology | 2000
Jodi S. Dashe; Lawrence Nathan; Donald D. McIntire; Kenneth J. Leveno
OBJECTIVE Pregnancies complicated by diabetes are frequently characterized by an increased volume of amniotic fluid, and the pathophysiologic mechanism of this increase is not known. Our goal was to evaluate the relationship between amniotic fluid glucose concentration and the amniotic fluid index in pregnancies complicated by insulin-treated diabetes and to compare it with that seen in normal pregnancies. STUDY DESIGN Amniotic fluid index and amniotic fluid glucose levels were measured before elective repeated cesarean delivery in 41 women with insulin-treated diabetes and in 35 women without diabetes. Only singleton gestations without anomalous fetuses were included. Women with diabetes were hospitalized for approximately 4 weeks before delivery, during which time glycemic control was optimized. Amniotic fluid index and amniotic fluid glucose concentration were correlated with each other and were compared between the groups with and without diabetes. RESULTS The mean amniotic fluid index was significantly increased in the diabetes group (16.6 +/- 5.0 cm in the diabetes group vs 13.4 +/- 3.5 cm in the control group; P =.002). The amniotic fluid glucose concentration was also significantly greater in the diabetes group than in the control group (39 +/- 17 mg/dL in the diabetes group vs 24 +/- 11 mg/dL in the control group; P <.001). Among women with diabetes the amniotic fluid glucose concentration was significantly correlated with the amniotic fluid index (r = 0.32; P =.04), a correlation not found among the control women. The mean fasting blood glucose concentration among the women with diabetes for the week before amniocentesis was 82 +/- 11 mg/dL. CONCLUSION The amniotic fluid index parallels the amniotic fluid glucose level among women with diabetes. This finding raises the possibility that the hydramnios associated with diabetes is a result of increased amniotic fluid glucose concentration.
Journal of Ultrasound in Medicine | 1993
Lawrence Nathan; Diane M. Twickler; Mark T. Peters; Pablo J. Sánchez; George D. Wendel
Fetal syphilis is the presumed diagnosis when the sonographic findings of fetal hydrops are found in the presence of maternal syphilis. In the absence of fetal hydrops, the diagnosis of fetal infection is difficult. We hypothesized that intra‐amniotic infection would be accompanied by anatomic placental and fetal abnormalities that could be detected by ultrasonography. Rabbit infectivity testing (RIT), intratesticular inoculation of rabbits with amniotic fluid, can be used to confirm intra‐amniotic infection with Treponema pallidum. Twenty‐one gravidas with untreated early (primary, secondary, and early latent) syphilis underwent sonography and amniocentesis for RIT at 24 weeks of gestation or later. Antenatal sonographic findings were compared to their amniotic fluid RIT results. Hepatomegaly was significantly (P < 0.01) associated with amniotic fluid infection detected by RIT. Antenatal detection of hepatomegaly, which is probably the initial sonographic manifestation of hydrops fetalis, may ultimately identify the fetus affected with congenital syphilis.
Infectious Diseases in Obstetrics & Gynecology | 1994
Lawrence Nathan; Kenneth J. Leveno
There appears to be a resurgence of puerperal sepsis due to a historically important pathogen, group A β-hemolytic streptococcus.
Infectious Diseases in Obstetrics & Gynecology | 1995
Alex Allaire; Lawrence Nathan; Mark G. Martens
Chlamydia trachomatis is a sexually transmitted disease (STD) commonly diagnosed in pregnancy. C. trachomatis has been linked to several pregnancy complications including premature rupture of membranes (PROM), preterm labor and birth, low birth weight, intrauterine growth retardation, and postpartum endometritis. Infants born to mothers through an infected birth canal are at risk for acquiring C. trachomatis pneumonitis, conjunctivitis, and nasopharyngeal infection. The standard treatment of C. trachomatis in pregnancy is erythromycin. Recently, amoxicillin and clindamycin have been added as alternative regimens for those patients intolerant of erythromycin. This paper reviews the effectiveness and tolerance of the alternative regimens compared with erythromycin and the success of antepartum treatment of chlamydia in preventing the poor pregnancy outcome and neonatal morbidity associated with C. trachomatis.
Obstetrical & Gynecological Survey | 1993
Lawrence Nathan; Diane M. Twickler; Mark T. Peters; Pablo J. Sánchez; George D. Wendel
Fetal syphilis is the presumed diagnosis when the sonographic findings of fetal hydrops are found in the presence of maternal syphilis. In the absence of fetal hydrops, the diagnosis of fetal infection is difficult. We hypothesized that intra-amniotic infection would be accompanied by anatomic placental and fetal abnormalities that could be detected by ultrasonography. Rabbit infectivity testing (RIT), intratesticular inoculation of rabbits with amniotic fluid, can be used to confirm intra-amniotic infection with Treponema pallidum. Twenty-one gravidas with untreated early (primary, secondary, and early latent) syphilis underwent sonography and amniocentesis for RIT at 24 weeks of gestation or later. Antenatal sonographic findings were compared to their amniotic fluid RIT results. Hepatomegaly was significantly (P < 0.01) associated with amniotic fluid infection detected by RIT. Antenatal detection of hepatomegaly, which is probably the initial sonographic manifestation of hydrops fetalis, may ultimately identify the fetus affected with congenital syphilis.
Prenatal Diagnosis | 1997
Lawrence Nathan; Van R. Bohman; Pablo J. Sánchez; N. Kristine Leos; Diane M. Twickler; George D. Wendel
Obstetrics & Gynecology | 1993
Lawrence Nathan; Roger E. Bawdon; Sidawi Je; Stettler Rw; McIntire Dm; George D. Wendel
Journal of Reproductive Medicine for the Obstetrician and Gynecologist | 1995
Lawrence Nathan; Andrew J. Satin; Diane M. Twickler