Re: "Labor and delivery events and risk of sudden infant death syndrome (SIDS)".
Explore the source record for details and available documents.
Breech Presentation↗
Biomedical subjects
D E Hickok
Publications and source records attributed to D E Hickok.
The frequency of breech presentation by gestational age at birth: a large population-based study.
From a study of birth records, breech presentation at delivery for each gestational age was found to be less frequent as compared with other reports about antenatal ultrasonographic examination. Selection bias or the effect of labor may account for the observed difference.
Birth Certificates↗
Percutaneous umbilical blood sampling: results from a multicenter collaborative registry. The Western Collaborative Perinatal Group.
Percutaneous umbilical blood sampling has become an important diagnostic tool in the evaluation of fetal health. Although recent reports have established the safety of this procedure, most have arisen from single centers with extensive experience. The Western Perinatal Collaborative Group has maintained a continuous registry of percutaneous umbilical blood sampling performed at the 13 member institutions for the years 1986 through 1990. During this period 302 procedures were performed. Primary indications for percutaneous umbilical blood sampling included Rh and non-Rh isoimmunization, intrauterine growth retardation, nonimmune hydrops, fetal anomalies, immune thrombocytopenia purpura, and rapid fetal chromosome analysis. Percutaneous umbilical blood sampling was successfully performed in 93.7% of cases with a sample withdrawn by a single puncture in 80.5% of attempts. In the majority of cases a 22-gauge needle was used. Postprocedural fetal death resulted in six cases (2.1%) and was most often associated with fetal anomalies or an abnormal karyotype. In conclusion, evaluation of the fetal state by percutaneous umbilical blood sampling is a safe and easily performed procedure, as demonstrated by a collaborative multicenter study.
Blood Specimen Collection↗
Elevated maternal serum alpha-fetoprotein levels and midtrimester placental abnormalities in relation to subsequent adverse pregnancy outcomes.
OBJECTIVE: Unexplained elevations of maternal serum alpha-fetoprotein levels in the second trimester of pregnancy are associated with adverse pregnancy outcomes, including intrauterine growth retardation, preterm delivery, preeclampsia, and abruptio placentae. In addition, elevations of maternal serum alpha-fetoprotein have been associated with placental lesions detected during second-trimester ultrasonographic evaluations. We examined the relationship between adverse pregnancy outcomes and unexplained elevations of maternal serum alpha-fetoprotein and placental abnormalities in the second trimester of pregnancy. STUDY DESIGN: During the period from January 1989 to March 1991 we conducted a cohort study of 201 women with an elevated maternal serum alpha-fetoprotein (> or = 2.0 multiples of the median) and a second-trimester ultrasonographic evaluation at Swedish Hospital Medical Center and 211 women with normal maternal serum alpha-fetoprotein levels who had also undergone ultrasonographic evaluation at the same institution. All women in this investigation had singleton pregnancies without fetal anomalies. RESULTS: Elevated maternal serum alpha-fetoprotein was associated with the following adverse pregnancy outcomes: low birth weight (adjusted risk ratio 3.7), preterm delivery (adjusted risk ratio 3.6), intrauterine growth retardation (adjusted risk ratio 4.0), preeclampsia (adjusted risk ratio 3.8) and abruptio placentae (adjusted risk ratio 4.8). Placental abnormalities detected during second-trimester ultrasonographic evaluations were also associated with adverse pregnancy outcomes: low birth weight (adjusted risk ratio 2.0), preterm delivery (adjusted risk ratio 2.3), intrauterine growth retardation (adjusted risk ratio 1.4), and abruptio placentae (adjusted risk ratio 9.0). A joint positive history of second-trimester elevations of maternal serum alpha-fetoprotein and placental abnormalities was more strongly associated with the following adverse infant outcomes: low birth weight (adjusted risk ratio 6.9), preterm delivery (adjusted risk ratio 5.6), and intrauterine growth retardation (adjusted risk ratio 5.3). CONCLUSIONS: Unexplained elevated levels of maternal serum alpha-fetoprotein and placental abnormalities detected in the second trimester of pregnancy are associated with particularly poor pregnancy outcome. Careful examination for placental abnormalities should be part of the evaluation of elevated maternal serum alpha-fetoprotein.
Birth Weight↗
Low birth weight and preterm delivery in relation to early-gestation vaginal bleeding and elevated maternal serum alpha-fetoprotein.
OBJECTIVE: To determine whether early-gestation vaginal bleeding and elevated maternal serum alpha-fetoprotein (MSAFP) are independent risk factors for adverse infant outcomes. METHODS: We conducted a cohort study of 201 women with an elevated MSAFP (at least 2.0 multiples of the median [MOM]) and a second-trimester ultrasound evaluation at Swedish Hospital Medical Center between January 1989 and March 1991, and 211 women with MSAFP levels below 2.0 MOM who had also undergone ultrasound evaluations during the same period. RESULTS: Stratified analyses demonstrated that early-gestation bleeding and elevated MSAFP were independent risk factors for the delivery of both preterm and low birth weight infants. Compared with women with no history of early-gestation bleeding or elevated MSAFP, women with early-gestation bleeding alone had a relative risk (RR) of preterm delivery of 4.3 (95% confidence interval [CI] 1.5-12.1); non-bleeders with elevated MSAFP had an RR of 4.6 (95% CI 1.9-10.9). A combined history of early-gestation bleeding and elevated MSAFP was associated with an almost sixfold increased risk of preterm delivery (RR 5.8; 95% CI 2.2-15.6). Analyses restricted to women with normal-appearing appearing placentas by second-trimester ultrasound evaluations yielded similar results. CONCLUSIONS: These findings support an earlier report documenting the independence of early-gestation bleeding and elevated MSAFP as predictors of adverse infant outcomes.
Cohort Studies↗
Cesarean section before the onset of labor and subsequent motor function in infants with meningomyelocele diagnosed antenatally.
Background. Meningomyelocele can now be detected before birth. Few data are available on its natural history, however, and optimal management at the time of delivery is controversial, although it has been suggested that labor and vaginal delivery may cause pressure on exposed nerve roots, resulting in additional loss of neural function. Methods. To assess the effect of labor and the type of delivery on the level of motor function in fetuses with uncomplicated meningomyelocele, we identified 200 cases of this disorder, accounting for 95 percent of the cases that occurred in the state of Washington during our 10-year study period. We compared the outcomes of 47 infants delivered by cesarean section before labor began, 35 delivered by cesarean section after a period of labor, and 78 who were delivered vaginally (another 40 were ineligible for the study). In cases of meningomyelocele detected prenatally, cesarean section was performed before the onset of labor if isolated meningomyelocele without severe hydrocephalus was present. The infants delivered in this manner were compared with those who were delivered either vaginally or by cesarean section after labor began. Results. At two years of age, the infants who had been exposed to labor were 2.2 times more likely to have severe paralysis than those delivered by cesarean section without labor (95 percent confidence interval, 1.7 to 2.8). Infants delivered by cesarean section before the beginning of labor had a mean (+/- SD) level of paralysis 3.3 +/- 3.0 segments below the anatomical level of the spinal lesion at two years of age, as compared with 1.1 +/- 2.3 for infants delivered vaginally and 0.9 +/- 4.1 for infants delivered by cesarean section after the beginning of labor (P less than 0.001 for both comparisons). Exposure to labor did not affect the frequency of neonatal complications or later intellectual performance. Conclusions. For the fetus with uncomplicated meningomyelocele, delivery by cesarean section before the onset of labor may result in better subsequent motor function than vaginal delivery or delivery by cesarean section after a period of labor.
Cesarean Section↗
Transcervical chorionic villus sampling and midtrimester oligohydramnios.
To study the possible association between transcervical chorionic villus sampling and midtrimester oligohydramnios, we conducted a prospective cohort study of all women who were seen for genetic counseling in the first trimester during a 2-year period. Women who chose chorionic villus sampling were compared with women who chose traditional amniocentesis for incidence of midtrimester oligohydramnios. Of 442 women exposed to chorionic villus sampling with a normal fetal karyotype, severe oligohydramnios developed in 12 (2.7%) at 16 to 23 weeks' gestation. None of the 391 women with normal fetal karyotypes who were counseled at the same time in pregnancy but who chose amniocentesis had oligohydramnios at the time of amniocentesis (p = 0.01). A nested case-control analysis was performed within the chorionic villus sampling group to evaluate risk factors associated with midtrimester oligohydramnios. Midtrimester oligohydramnios occurring after chorionic villus sampling was associated with postprocedure bleeding and elevated maternal serum alpha-fetoprotein (p less than 0.01). There were no perinatal survivors with midtrimester oligohydramnios.
Adult↗
Maternal smoking and placenta previa.
We conducted a case-control study of the relation between smoking and placenta previa, using Washington State birth certificate data from 1984 through 1987. The study population was comprised of live, singleton births to women whose pregnancies were complicated by placenta previa (N = 598) and randomly selected controls (N = 2,422) from the same time period. We used logistic regression to estimate odds ratios (OR) and their 95% confidence intervals (CI). Maternal smoking approximately doubled the risk of placenta previa after adjustment for the confounding effect of maternal age (OR = 2.1, 95% CI: 1.7-2.5).
Adult↗
Femur length shortening in the detection of Down syndrome: is prenatal screening feasible?
The potential utility of screening for femur length shortening in prenatal detection of Down syndrome (trisomy 21) was evaluated by comparing 49 consecutive fetuses with Down syndrome with 572 chromosomally normal fetuses before genetic amniocentesis. Ratios of measured femur length/predicted femur length and biparietal diameter/femur length were calculated for each fetus. The predicted femur length was calculated from a regression equation relating the biparietal diameter and femur length derived from a sample control group. With this normal regression equation, 7 of 49 (14.3%) fetuses with Down syndrome had short femur lengths (measured femur length/predicted femur length ratio of less than or equal to 0.91) compared with 35 of 572 (6.1%) fetuses with a normal karyotype (p less than 0.05). However, the maximum positive predictive value for identification of Down syndrome based on short femur lengths was only 0.93% for a high-risk population (prevalence of Down syndrome, 1:250) and 0.33% for a low-risk population (prevalence of Down syndrome, 1:700). We conclude that ultrasonographic screening of short femur length is less effective for prenatal detection of Down syndrome than initially suggested.
Cephalometry↗
The "stuck twin" phenomenon: ultrasonographic findings, pregnancy outcome, and management with serial amniocenteses.
Thirteen consecutive twin pregnancies affected by the "stuck twin" phenomenon were reviewed to determine the potential benefit of serial amniocenteses. The fetal survival rate for the eight pregnancies that underwent serial amniocenteses was 69% (11 of 16 fetuses). This is significantly improved compared with a fetal survival rate of 20% among the five preceding pregnancies managed without serial amniocenteses at the same institution (p = 0.01). It is also markedly improved compared with a combined fetal survival rate of 16% among 48 previously reported pregnancies with the stuck twin phenomenon managed without serial amniocenteses (p less than 0.0001). Survival correlated with the absence of concomitant pregnancy complications (i.e., maternal hypertension or intractable labor) and with the absence of severe fetal structural abnormalities. Procedural complications occurred in three of eight pregnancies (37.5%) managed with serial amniocenteses and was attributed as a cause of fetal death in one case. Two of 11 survivors (18%) had complications after serial amniocenteses including brain infarction and renal tubular necrosis. Serial amniocenteses may significantly improve the survival rate of twin gestations affected by the stuck twin phenomenon but may be associated with complications among survivors.
Amniocentesis↗
Epidemiology and diagnosis of twin gestation.
Explore the source record for details and available documents.
Epidemiologic Factors↗
Translabial ultrasound of the third-trimester uterine cervix. Correlation with digital examination.
This prospective blinded study compared translabial ultrasound (TLU) and digital palpation of the cervix among women whose cervix could not be visualized adequately or at all with transabdominal ultrasound during the third trimester of pregnancy. The cervical canal and internal cervical os were adequately visualized during 109 of 113 TLUs (96%). The TLU was well tolerated by the patients; only two patients refused the TLU pending discussion of the technique with their obstetrician. Among 43 examinations of patients without clinical cervical effacement, TLU showed a cervical length of 2.5 to 4.2 cm (mean, 2.9 cm). An excellent correlation (R = 0.90) was noted between cervical length on TLU and percentage of cervical effacement on digital examination. The correlation between amount of cervical dilatation on TLU and on digital examination was not high (R = 0.58). We conclude that the measurements of cervical length on TLU correlate well with the amount of cervical effacement on digital examination and that TLU provides a rapid and well-tolerated alternative technique to visualize the third-trimester uterine cervix.
Cervix Uteri↗
Prenatal sonographic findings of Down syndrome: review of 94 cases.
Prenatal ultrasound findings were reviewed in 94 consecutive fetuses with proved Down syndrome (trisomy 21) during a 6-year period at a single institution. One or more abnormalities were found in 31 fetuses (33%), including two of 11 fetuses seen before 14 weeks, 17 of 68 fetuses seen between 14-24 weeks, and 12 of 15 fetuses seen after 24 weeks. Major anomalies detected included cardiac defects (five), duodenal atresia (four), cystic hygromas (four), omphalocele (two), hydrops (two), and hydrothorax (one). Nuchal thickening was observed in five fetuses, including four of 25 second-trimester fetuses evaluated prospectively during the last 2 years of the study. Mild cerebral ventricular dilatation (three) and hyperechogenic bowel (five) are new findings that have not been generally associated with Down syndrome. A variety of prenatal sonographic abnormalities may be associated with Down syndrome, and the frequency of detecting most abnormalities increases with menstrual age. Anomalies more frequently detected before 20 weeks include cystic hygromas, nuchal thickening, and hyperechogenic bowel. Awareness of the sonographic findings associated with Down syndrome should result in improved detection of this disorder.
Abnormalities, Multiple↗
The relationship of abruptio placentae with maternal smoking and small for gestational age infants.
A population-based case-control study was conducted to examine the relationship between maternal smoking and the occurrence of abruptio placentae and to assess the joint relationship of smoking and small for gestational age (SGA) status with abruption. Cases (N = 1089) reported on Washington state birth certificates from 1984-1986 were compared with randomly selected births (N = 2323) from the same period. The occurrence of placental abruption was associated with both smoking (relative risk = 1.6; 95% confidence interval 1.3-1.8) and SGA status (relative risk = 2.6; 95% confidence interval 2.0-3.3). The association with SGA status was identical for smokers and non-smokers. Thus, the increase of SGA infants in women whose pregnancies are complicated by abruption is not explained by maternal smoking, and in some cases may result from placental dysfunction induced by the process of placental separation.
Abruptio Placentae↗
The association between decreased amniotic fluid volume and treatment with nonsteroidal anti-inflammatory agents for preterm labor.
From a cohort of women treated for preterm labor at the Swedish Hospital Medical Center for a 1-year period, 58 patients were identified as receiving one or more tocolytic agents. Twenty-seven of the 58 patients met study criteria for the determination of the effects of tocolytic therapy on amniotic fluid volume both before and during treatment by means of ultrasound examination. Fourteen of 17 patients (82.3%) treated with nonsteroidal anti-inflammatory drugs demonstrated a decrease in amniotic fluid, whereas none of the 10 patients treated with other tocolytic agents experienced a decrease in fluid volume. Decreased amniotic fluid associated with nonsteroidal anti-inflammatory drug treatment was reversible in seven of eight patients when treatment was discontinued and ultrasound examinations were performed after treatment.
Adult↗
Unexplained second trimester oligohydramnios: a clinical-pathologic study.
The importance of oligohydramnios in the absence of fetal malformations has been recognized because of the associated high risk for adverse pregnancy outcome. Pathologic dissections were performed on four fresh fetuses whose mothers were identified by ultrasound as having oligohydramnios and had no clinical history or physical evidence of vaginal leakage of amniotic fluid. The fetuses were all normal except for hypoplasia of the lungs and varying degrees of Potter's facies. The kidneys were histologically normal but had increased weight. The more widespread use of ultrasound may have allowed us to detect an earlier stage of a previously present type of pregnancy failure.
Abortion, Induced↗
Weight gain patterns during twin gestation.
Few data are available about desirable weight gain during twin gestation. The present study addresses this issue through retrospective evaluation of 217 women pregnant with twins who delivered at Swedish Hospital Medical Center, Seattle, between 1982 and 1986. The purpose of the study was to identify an optimum total weight gain and an optimum weight gain pattern for normal twin gestation. A mean prenatal weight gain of 20 kg (44 lb) was associated with "optimum" outcome; optimum outcome was defined as a pregnancy lasting at least 37 weeks with the delivery of two living infants weighing greater than or equal to 2,500 gm each with 5-minute Apgar scores greater than or equal to 7. A weight gain curve for twin gestation was generated and compared with the standard curve for singleton pregnancy. While the weight gain curve during twin gestation was similar to the standard curve during the first half of pregnancy, increased weight gain began in the second trimester and continued to term. The weight gain pattern of twin gestations with less-than-optimum outcome paralleled that of the optimum outcome group until about 30 weeks' gestation, at which time weight gain slowed in women in the former group, whose mean total weight gain was 16.8 kg (37 lb).
Adult↗
Maternal serum alpha-fetoprotein is a marker for fetal anomalies in pediatric surgery.
Maternal serum alpha-fetoprotein (MS-AFP) screening has become part of routine obstetric care. Although elevated MS-AFP was originally associated with neural tube defects (NTD), it is also able to detect several fetal anomalies of interest to a pediatric surgeon, ie, ventral abdominal wall defects, intestinal atresias, and sacrococcygeal teratomas. Previously, decreased MS-AFP had only been associated with fetal trisomies, but not surgically correctable lesions. In the present study, we review our recent experience with both elevated and decreased MS-AFP as a marker to detect fetal anomalies of concern to the pediatric surgeon. Forty-one fetal anomalies were associated with 333 pregnancies referred for follow-up after abnormal MS-AFP screening results from November 1985 through November 1986. One hundred ninety-six were elevated and 139 were decreased. In most cases, evaluation included counseling, repeat MS-AFP, level II ultrasound, and amniocentesis. This revealed elevated MS-AFP to be associated with 32 (16.3%) anomalies (2 NTD, 5 anencephalics, 5 ventral abdominal wall defects, 1 stage IV-S neuroblastoma, 1 renal anomaly, 1 ventriculomegaly, 15 fetal demises, and 2 fetal-maternal bleeds). Decrease in MS-AFP was associated with nine (6.4%) anomalies (2 congenital diaphragmatic hernias, 3 Down's syndrome, 1 Turner's syndrome, 2 duodenal atresias, and 1 choroid plexus cyst). In this study, MS-AFP detected several fetal anomalies known to be associated with abnormal MS-AFP and three anomalies not previously described (congenital diaphragmatic hernia, neuroblastoma, and choroid plexus cyst). Elevated as well as decreased MS-AFP are significant and should be pursued by a full prenatal evaluation.(ABSTRACT TRUNCATED AT 250 WORDS)
Algorithms↗