Decreased amniotic fluid index in low-risk pregnancy.

OBJECTIVE: To evaluate the perinatal outcomes of pregnancies complicated by isolated decreased amniotic fluid volume (AFI) after 30 weeks' gestation (AFI < or = 5 or > 5 cm but < 2.5th percentile). STUDY DESIGN: We retrospectively studied 150 low-risk singleton pregnancies > 30 weeks' gestation with decreased AFI. We also compared the outcomes of 57 pregnancies with AFI < or = 5 cm to those of 93 pregnancies with AFI > 5 cm but < 2.5th percentile (borderline AFI). Pregnancy outcome was assessed with respect to antepartum, intrapartum and neonatal measures. Statistical significance (P < .05) between groups was determined by means of the Student t test and chi 2 analysis. RESULTS: There were no statistically significant differences between pregnancies with AFI < or = 5 cm and those with AFI > 5 cm but < 2.5th percentile with respect to labor induction for an abnormal nonstress test (7.0% vs. 7.5%, overall 7.3%), cesarean sections for fetal heart rate abnormalities (7.0% vs. 7.5%, overall 7.3%), presence of meconium (16.1% vs. 15.7%, overall 16%) and Apgar score < 7 at five minutes (0 vs. 1.1%, overall 0.66%). There were no perinatal deaths in either group. Antepartum variable decelerations were more common in pregnancies with AFI < or = 5 cm as compared to those with AFI > 5 cm but < 2.5th percentile (63.1% vs. 45.1%, P = .007; overall 53.3%). CONCLUSION: With antepartum monitoring, perinatal outcome in low-risk pregnancies with an isolated decreased AFI after 30 weeks' gestation (< or = 5 or > 5 cm but < 2.5th percentile) appears to be good.

Placental IGF-I in severe intrauterine growth retardation.

IGF-I, which is produced by intrauterine tissues including the placenta, has been implicated as a possible factor in intrauterine growth retardation (IUGR). We hypothesized that placental IGF-I production may be aberrant in pregnancies affected by IUGR. A placental perifusion system was utilized to study the release of IGF-I in placentas from normotensive severe IUGR (birthweight < 5%, (n = 9)) and normal control pregnancies (n = 5). For each placenta, tissues were perifused and samples were collected from hour 5 to hour 10. IGF-I was measured by radioimmunoassay after acid extraction. The cumulative release of total IGF-I from the control placentas from hour 5 to hour 10 of perifusion was 15,417 +/- 1,337 pg/g (mean +/- SEM), and decreased approximately 45% from hour 5 through hour 10 of perifusion. The pattern of IGF-I release, as well as the absolute mass of IGF-I, from six of the nine IUGR placentas was similar to the controls. However, three of the nine IUGR placentas demonstrated a significantly different IGF-I release pattern, i.e., IGF-I release did not decrease throughout the perifusion period. These three placentas also had abnormal absolute production rates of IGF-I, i.e., significantly elevated in one and significantly decreased in two. IGF-I production and release were normal in some IUGR placentas, although in certain cases of IUGR, the placental production and release pattern were aberrant. We conclude that abnormal regulation and production of IGF-I by the placenta may be a factor affecting certain pregnancies complicated by IUGR.

Effect of excessive GnRH-binding substance on circulating maternal hCG in human pregnancy.

Gonadotropin-releasing hormone (GnRH) can stimulate the release of placental human chorionic gonadotropin (hCG). Thus, at the onset of these studies it was the objective to define the relationship of hCG to GnRH in the maternal circulation throughout pregnancy, focusing on early pregnancy. Blood samples were collected at 8, 10, 12, 14, 16, 28 and 36 weeks of gestation during labor and the GnRH and hCG levels were determined by radioimmunoassay. Of 39 pregnancies, a GnRH-binding substance was found in the maternal circulation of three. This GnRH-binding substance resulted in erroneous GnRH levels, due to the very high non-specific binding. In the pregnant women without this GnRH-binding substance, GnRH attained highest concentrations at 12-14 weeks. The typical peak of hCG at 8-10 weeks of gestation was observed in this group, while the group of patients having the GnRH-binding substance had significantly lower hCG levels. Each of the patients with circulating GnRH-binding substance had prior pregnancy(s) and two of the three had a prior pregnancy loss. The nature of this GnRH-binding substance was investigated using gel chromatography. After incubation of [125I]GnRH with patient plasma for 3 days this substance was shown to be of high molecular weight which was ethanol precipitable. This binding substance may therefore be an antibody, since it appears to be a high molecular weight protein requiring a number of days to bind the [125I] GnRH. This GnRH-binding substance may be of physiological importance, since the circulating hCG level was significantly less in the group of patients with this substance than in those without.

Effect of IGF-I on placental thromboxane and prostacyclin release in severe intrauterine growth retardation.

Our recent findings that IGF-I inhibits placental thromboxane (TxB2) release (1, 2) and that prostanoid release from placentas or certain pregnancies complicated by intrauterine growth retardation (IUGR) is decreased [Sorem KA, Siler-Khodr TM, Placenta, 16:503-515, 1995] led us to investigate the effect of IGF-I on prostanoid release from placentas of IUGR pregnancies. The placental response of 6-keto-prostaglandin F1a (6-keto-PGF1a) and thromboxane (TxB2) to IGF-I in severe IUGR (n = 5) was compared with the response in normal pregnancies (n = 6). Placentas were perifused with medium containing IGF-I at doses of 0, 5.2, 10.4, 20.8, and 83.3 ng/ml. In three of the five IUGR placentas (responsive group), incubation with IGF-I resulted in an inhibition of TxB2, attaining significantly greater inhibition at a lower dose of IGF-I than the normal placental response. However, in two of the five IUGR placentas (non-responsive group), the TxB2 was insensitive to the normal inhibitory action of IGF-I. The baseline production of prostanoids from the IUGR placentas was not predictive of their response to IGF-I. Moreover, 6-keto-PGF1a was not inhibited in any of the placentas, IUGRs, or normals. However, the ratio for TxB2 over 6-keto-PGF1a basal production rate from the zero treatment time to the fifth hour was significantly less in the nonresponsive IUGR placentas than for the responsive IUGR placentas or for the normal placentas. Certain IUGR placentas demonstrated a significant suppression of TxB2 with IGF-I, whereas other IUGR placentas were insensitive to exogenous IGF-I. A decreased and unchanging ratio of TxB2/6-keto-PGF1a production rate was characteristic of the nonresponders.

Physical and sexual abuse in a middle-class obstetric population.

To evaluate the prevalence of a history of physical and sexual abuse in pregnant, economically stable, middle-class women with access to comprehensive health care, we issued self-report questionnaires to prenatal orientation classes at Wilford Hall Medical Center from October 19, 1992, to March 15, 1993. After identifying women who had been physically or sexually abused, we identified the assailant, the number of occurrences, and injuries resulting from the abuse. Of the 563 women who responded, 100 (18%) reported previous physical or sexual abuse. Seven women (1%) stated that they were physically abused during the pregnancy. Women were more likely to be physically than sexually abused by a spouse or lover (46% versus 13%). To identify women who have a history of abuse and to address their needs, practitioners should incorporate taking a history of physical and sexual abuse during the routine new obstetric visit.

Circulating maternal corticotropin-releasing hormone and gonadotropin-releasing hormone in normal and abnormal pregnancies.

OBJECTIVE: Corticotropin-releasing hormone and gonadotropin-releasing hormone are produced by the human placenta and have been measured in the maternal circulation during pregnancy. Our objective was to determine concentrations of these substances in maternal plasma throughout normal pregnancies and in early pregnancy loss. STUDY DESIGN: Fifty-one pregnant women were followed up prospectively and plasma samples were drawn at 8, 10, 12, 14, 16, 28, and 36 weeks' gestation and during labor. Specific and sensitive radioimmunoassays were used to determine corticotropin-releasing hormone and gonadotropin-releasing hormone concentrations in these samples. RESULTS: Blood samples were drawn at all time points and outcome data were available from 33 women who completed their pregnancies at term without complications. In this normal group circulating corticotropin-releasing hormone concentrations increased from low or undetectable concentrations at 8 weeks (< or = 23.2 +/- 1.3 pg/ml, mean +/- SEM) to measurable values at 16 weeks (34.3 +/- 2.2 pg/ml). Thereafter there was a significant increase to 1294 +/- 113 pg/ml in labor. Gonadotropin-releasing hormone demonstrated a trimodal distribution, increasing significantly from 8 to 14 weeks, decreasing at 16 weeks, and increasing again by term. The ratio of corticotropin-releasing hormone to gonadotropin-releasing hormone in the normal group demonstrated a 30-fold increase from 8 weeks to term. In eight cases of early pregnancy loss corticotropin-releasing hormone and gonadotropin-releasing hormone concentrations were not significantly different from those of the normal group in early pregnancy. In two cases of premature delivery gonadotropin-releasing hormone concentrations and ratios were within the normal range; corticotropin-releasing hormone levels were normal in both cases of premature delivery. CONCLUSION: In this study we determined maternal concentrations of corticotropin-releasing hormone and gonadotropin-releasing hormone in normal pregnancies and in labor at term. Neither maternal concentrations of corticotropin-releasing hormone nor gonadotropin-releasing hormone were useful in identifying pregnant women at risk for early pregnancy loss.

The impact of sexual abuse on job attrition in military recruits.

OBJECTIVE: To determine whether recruits entering the U.S. Air Force with a history of sexual abuse had a higher attrition rate from basic military training (BMT). METHODS: Retrospective, case-control study involving 28,918 recruits entering BMT from October 1, 1991, to September 30, 1992. Self-report questionnaires were given to all recruits on the second day of BMT. We compared recruits revealing a history of sexual abuse to all other recruits at the end of BMT and at the end of the next fiscal year. RESULTS: We found that victims of sexual abuse had a higher attrition rate from BMT than non-victims (10.6 versus 4.1%, p < 0.0001). Four and one-tenth percent of all recruits (1,289) reported a history of sexual abuse, and fewer male than female recruits reported a history of sexual abuse (1.5 versus 15.1%, p < 0.0001). However, after BMT there were no differences in any job performance indicators between victims and non-victims. CONCLUSION: We conclude that recruits with a history of sexual abuse had a higher attrition rate from BMT than those without a history of abuse; however, those recruits who did complete BMT were as successful as those who did not report a similar history of abuse.

Advanced triploid pregnancy and preeclampsia.

Triploidy, though unusual in advanced gestations, may be associated with preeclampsia. The increase in paternal genetic material associated with the triploid diandric placenta may support the role of immunologic factors in the development of preeclampsia.

Placental prostanoid release in severe intrauterine growth retardation.

Our objective was to evaluate prostanoid release from the placentae of pregnancies complicated by severe intrauterine growth retardation (IUGR) and without hypertension, compared with placentae from normal, uncomplicated term pregnancies. A perifusion system was utilized to study the release of prostanoids 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), thromboxane B2(TxB2), prostaglandin E2 (PGE2) and prostaglandin F2 alpha (PGF2 alpha) from human placentae from pregnancies complicated by normotensive severe IUGR (n = 9, five at term and four preterm) and normal control pregnancies (n = 6). For each placenta, triplicate chambers of tissue were perifused at a rate of 6 ml/h, and samples were collected from hours 5-10. Prostanoids were measured using specific and sensitive radioimmunoassays. In the IUGR group, the basal placental production of the vasoconstrictor thromboxane was not increased, nor was the ratio of cumulative TxB2 to 6-keto-PGF1 alpha elevated compared with normal term controls. In three term IUGR placentae, the ratio was significantly decreased compared with controls. The basal placental production of the vasoconstrictor PGF2 alpha was likewise not increased compared with controls, nor was the ratio of PGF2 alpha to PGE2 elevated. Two of the placentae in the term IUGR group demonstrated significant elevations of PGE2 and 6-keto-PGF1 alpha. Overall, the IUGR placentae released normal or low normal levels of the prostanoids studied. The pattern of placental prostanoid release over time was similar to that of the normal term placentae. The term and preterm placentae of pregnancies complicated by severe IUGR did not exhibit an excess production of vasoconstrictor prostanoids. Therefore, strategies designed to reduce thromboxane production in severe IUGR without hypertension may be unjustified.

Measuring quantitative serum human chorionic gonadotropin. Variations in levels between kits.

Human chorionic gonadotropin (hCG) may be used in the monitoring of early pregnancy. It may also be used as a tumor marker in the diagnosis and follow-up of gestational trophoblastic disease, choriocarcinoma and testicular carcinoma. The combination of maternal serum unconjugated estriol, alpha-fetoprotein and quantitative hCG has shown promise as an antepartum screen for Down syndrome. In the quantitative assessment of hCG, the calibrators used by various kits are standardized to one of two different standards, either the Second International Standard or the First International Reference Preparation (IRP), established by the World Health Organization in 1968 and 1975, respectively. The IRP is now considered the Third International Standard, and both terms may be used interchangeably. Confusion may exist in clinical situations if quantitative hCG levels determined by assays in different laboratories using different standards are compared or used simultaneously. Practitioners are advised to be aware of which calibration standard is utilized in their laboratory and to interpret the results accordingly.

Dose-related effect of IGF-I on placental prostanoid release.

Prostanoids play an important role throughout all of pregnancy and during the initiation and progress of labor. The human placenta at term produces large quantities of prostanoids, yet little is known of the factors regulating their biosynthesis. In a previous study we observed that insulin-like growth factor I (IGF-I) specifically inhibits thromboxane B2 (TxB2) and prostaglandin F2 alpha (PGF2 alpha) from human term placental explants. In these studies we have defined the dose-related action of IGF-I on the release of placental prostanoids. With use of a perifusion system, the basal release of prostaglandin E2 (PGE2), PGF2 alpha, TxB2 and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) from human term placental explants increased from the fifth hour in culture, while the release of 13,14-dihydro-15-keto-PGF2 alpha (PGFM) remained constant. The addition of IGF-I (5.2-83.3 ng/mL) to the perifusing medium effected an inhibition of TxB2 and PGF2 alpha. The release of TxB2 was inhibited in a dose-related fashion from the initiation of IGF-I treatment and throughout the five hours of treatment, whereas the inhibition of PGF2 alpha was significant only at a dose of 83.3 ng/mL of IGF-I. Yet, the release of 6-keto-PGF1 alpha, PGE2, or PGFM was not altered by any dose of IGF-I studied. Because both TxB2 and PGF2 alpha are vasoconstrictors, we have proposed that IGF-I may enhance vasodilation in the placenta. Therefore, IGF-I may allow for increased blood flow, thus affecting the maintenance of pregnancy and the supply of nutrients available for the growth of the fetus.

Placenta increta complicating a first-trimester abortion. A case report.

Placenta increta complicating pregnancy in the first trimester is rare. A patient with risk factors for placenta increta required a hysterectomy to control a hemorrhage after a first-trimester abortion. Pathologic study confirmed the preoperative diagnosis of placenta increta.

Isolated fallopian tube torsion presenting in labor. A case report.

Isolated torsion of the fallopian tube was discovered during labor. Tubal torsion may occur in the absence of adnexal disease. Diagnosing this disorder is especially difficult in labor, when other causes, such as disruption of a prior uterine scar, may be considered.

Placenta membranacea with placenta increta: a case report and literature review.

The pregnancy of a patient with placenta membranacea associated with placenta increta and a live-born infant is described, and the literature covering placenta membranacea is reviewed. A total of 26 cases of placenta membranacea in the second and third trimesters have been reported. The condition appears to have an incidence of 1:20,000-40,000, and there have been 14 reported live births associated with this rare placental anomaly. Antepartum and postpartum hemorrhage were reported to complicate 83 and 50% of the cases, respectively. Approximately 30% of the cases involved some form of abnormal placental adherence.

Cancer incidence in the Zuni Indians of New Mexico.

The total age-adjusted incidence of cancer in the Zuni Indians of New Mexico was significantly lower than that of the New Mexico Anglo population during the period 1969-1982. Specific sites at which the Zunis had a significantly lower number of cases than expected, based on the rates for Anglos, are: colon, rectum and anus, lung, breast, endometrium, melanoma of the skin, pancreas, and the leukemias. Sites at which the Zunis had a higher number of cases than expected are stomach and gallbladder. The Zunis have a pattern of occurrence of cancer that is similar to other American Indians of New Mexico (Navajo, Apache, and Pueblo); however, rates of lung, colonic, and pancreatic cancer among the Zunis are significantly lower. The occurrence and anatomic distribution of cancer among the Zunis may be the result of cultural and environmental conditions or genetic influences. Further studies may clarify the risk factors which contribute to this pattern of disease.