Val Catanzarite

Oxytocin-associated rupture of an unscarred uterus in a primigravida.

BACKGROUND: Intrapartum rupture of the unscarred uterus is an uncommon event, usually associated with such risk factors as grand multiparity, malpresentation, history of gestational trophoblastic disease, or instrumented delivery. Rupture during first pregnancy is extremely rare. CASE: A 30-year-old primigravid woman was admitted for labor augmentation with oxytocin at 40.5 weeks of gestation. The oxytocin infusion rate was increased during the first and second stages of labor despite contractions occurring at a rate of 4–5 per 10 minutes. The uterus ruptured during second stage. Despite emergency cesarean delivery, the baby had evidence of severe asphyxia. CONCLUSION: This case of uterine rupture in a primigravida with no prior uterine surgery and a structurally normal uterus underscores the importance of careful contraction monitoring and judicious control of oxytocin infusion rates.

Second-trimester ultrasonography: determinants of visualization of fetal anatomic structures.

Little information has been published regarding rates of visualization of fetal anatomic structures or factors affecting visualization in unselected patients. We prospectively studied these points by scoring visualization of intracranial, spinal, cardiac, ventral wall, umbilical cord, stomach, bladder, and genital anatomy in 573 consecutive midtrimester scans in which no fetal anomalies were seen. Each feature was scored 0, 1, or 2, corresponding to poor, adequate, or optimal visualization, and these eight numbers were summed for an overall visualization score. Overall visualization fell abruptly beyond maternal weight 165 pounds (p less than 0.001) and rose with advancing gestational age (p less than 0.001). Placental location did not significantly influence visualization. Overall, an adequate screening scan, defined as adequate visualization of central nervous system, heart, stomach, ventral wall, bladder, and cord was obtained in 51% of scans, and optimal visualization of each of these in only 9% of cases. Factors that might improve anatomic visualization and the implications of these results for the use of ultrasonography in screening for congenital anomalies are discussed.

The N-terminal and C-terminal portions of the atrial natriuretic factor prohormone increase during preeclampsia

The influence of preeclampsia on the circulating concentrations of the 28-amino-acid carboxy terminus (C-terminus) (i.e., atrial natriuretic factor) and the amino terminus (N-terminus) of the 126-amino-acid atrial natriuretic factor prohormone (pro ANF) was studied in the third trimester with the use of three specific radioimmunoassays that recognize: (1) atrial natriuretic factor (i.e., amino acids 99 to 126), (2) the whole 98-amino-acid N-terminus, and (3) amino acids 31 to 67 from the midportion of the N-terminus of the prohormone. The C-terminus was significantly increased (p less than 0.001) in the third trimester in women with preeclampsia, the mean +/- SEM of 15 subjects was 150 +/- 7 pg/ml versus 89 +/- 7 pg/ml in the third trimester in 12 women during normal pregnancies and 65 +/- 2 pg/ml in 19 healthy nonpregnant women. The whole 98-amino-acid N-terminus, likewise, was significantly increased (p less than 0.001) in women with preeclampsia to 4706 +/- 629 pg/ml versus 2160 +/- 79 pg/ml in women in the third trimester of normal pregnancies and versus the circulating concentration of 1847 +/- 127 pg/ml in healthy nonpregnant women. ProANF 31 to 67 mean circulating concentration in preeclampsia was 4638 +/- 725 pg/ml, which was also significantly (p less than 0.001) increased compared with its mean circulating concentration in the third trimester of normal pregnancy of 1758 +/- 83 pg/ml or that in healthy nonpregnant women (1400 +/- 105 pg/ml). The circulating concentrations of both the N-terminus and C-terminus of the atrial natriuretic factor prohormone decreased within 24 hours after delivery in contrast to a normal pregnancy in which they both increase post partum. These results indicate a marked difference in the metabolism of both the N-terminus and the C-terminus of the atrial natriuretic factor prohormone in women with preeclampsia versus that in women with normal pregnancies or that in healthy nonpregnant women.

Prenatally Diagnosed Vasa Previa: A Single-institution Series of 96 Cases

OBJECTIVE: To describe outcomes for a large cohort of women with prenatally diagnosed vasa previa, determine the percentage in patients without risk factors, and compare delivery timing and indications for singletons and twins. METHODS: This was a retrospective case series of women with prenatally diagnosed vasa previa delivered at a single tertiary center over 12 years. Potential participants were identified using hospital records and perinatal databases. Patients were included if vasa previa was confirmed at delivery and by pathologic examination. Maternal and newborn data were gathered from medical records. RESULTS: There were 77 singleton and 19 twin pregnancies with a prenatal diagnosis of vasa previa. There was one neonatal death from congenital heart disease. Perinatal management of recommended elective hospitalizations with corticosteroid administration and elective early delivery resulted in average gestational age for delivery in singletons at 34.7±1.6 weeks and 32.8±2.2 weeks for twins. Among the 77 singletons, delivery was elective in 48, as a result of contractions or labor in 21, bleeding in four, nonreassuring tracing in two, asymptomatic cervical shortening in one, and preeclampsia in one. Among 19 twins, delivery was elective in six and for contractions or labor in 13. Sixty-eight percent of twins compared with 37% of singletons had nonelective delivery (P<.05). Delivery occurred by 32 weeks of gestation in 6.4% of singletons and 26% of twins (P<.05) and by 34 weeks of gestation in 11% of singletons and 58% of twins (P<.001). Six neonates (5.2%) had major anomalies, all prenatally detected. Respiratory distress syndrome occurred in 57.1% of singletons and 65.7% of twins. Nineteen singletons (24.7%) had no risk factors for vasa previa. CONCLUSION: Planned preterm delivery for women with prenatally diagnosed vasa previa resulted in elective delivery for singletons in 62% and for twins 32%. Gestational age at birth on average was 34.7 weeks for singletons and 32.8 weeks of gestation for twins. Major anomalies were frequent as was respiratory distress syndrome. Elective delivery between 34 and 35 weeks of gestation for singletons is reasonable. As a result of the high rate of nonelective delivery in twins, delivery at 32–34 weeks of gestation may be risk-beneficial. The high rate of singletons without risk factors for vasa previa reinforces the recommendation to screen routinely for cord insertion site.