Outcomes during delivery hospitalisations with inflammatory bowel disease.

OBJECTIVE: To characterise inflammatory bowel disease (IBD) trends and associated risk during delivery hospitalisations. DESIGN: Cross-sectional. SETTING: US delivery hospitalisations. POPULATION: Delivery hospitalisations in the 2000-2018 National Inpatient Sample. METHODS: This study analysed a nationally representative hospital discharge database based on the presence of IBD. Temporal trends in IBD were analysed using joinpoint regression to estimate the average annual percent change (AAPC). IBD severity was characterised by the presence of diagnoses such as penetrating and stricturing disease and history of bowel resection. Risks for adverse outcomes were analysed based on presence of IBD. Poisson regression models were performed with unadjusted and adjusted risk ratios (aRR) as measures of effect. MAIN OUTCOME MEASURE: Prevalence of IBD and associated adverse outcomes. RESULTS: Of 73 109 790 delivery hospitalisations, 89 965 had a diagnosis of IBD. IBD rose from 0.06% in 2000 to 0.21% in 2018 (AAPC 7.3%, 95% CI 6.7-7.9%). Among deliveries with IBD, IBD severity diagnoses increased from 4.1% to 8.1% from 2000 to 2018. In adjusted analysis, IBD was associated with increased risk for preterm delivery (aRR 1.50, 95% CI 1.47-1.53), severe maternal morbidity (aRR 1.93, 95% CI 1.83-2.04), venous thrombo-embolism (aRR 2.76, 95% CI 2.39-3.18) and surgical injury during caesarean delivery hospitalisation (aRR 5.03, 95% CI 4.76-5.31). In the presence of a severe IBD diagnosis, risk was further increased for all adverse outcomes. CONCLUSION: IBD is increasing in the obstetric population and is associated with adverse outcomes. Risk is increased in the presence of a severe IBD diagnosis. TWEETABLE ABSTRACT: Deliveries among women with inflammatory bowel disease are increasing. Disease severity is associated with adverse outcomes.

Population risk factors for nulliparous, term, singleton, vertex caesarean birth: a national cross-sectional study.

OBJECTIVE: To characterise medical, obstetric and demographic risk factors associated with nulliparous, term, singleton, vertex (NTSV) caesarean birth. STUDY DESIGN: Cross-sectional study. SETTING: United States delivery hospitalisations. POPULATION: NTSV births in 2016-18 US natality data. METHODS: This study analysed a national sample of natality data generated by the United States National Vital Statistics System. NTSV deliveries were identified. The primary outcome was caesarean birth. Risk factors including maternal age, body mass index (BMI) and pregestational diabetes were analysed. Multivariable log-linear regression models analysed factors associated with NTSV caesarean with adjusted risk ratios (aRR) as measures of effect. RESULTS: Of 11 622 400 deliveries, 3 764 707 met NTSV criteria, and their caesarean section rate was 25.9%. Maternal age 35-39 years (aRR 1.51, 95% CI 1.50-1.52) and 40-54 years (aRR 2.03, 95% 2.00-2.05) compared with age 19-34 years; BMI 25 to <30 kg/m2 (aRR 1.32, 95% CI 1.31-1.33), 30 to <35 kg/m2 (aRR 1.57 95% CI 1.56-1.58), 35 to <40 kg/m2 (aRR 1.82, 95% CI 1.80-1.83) and ≥40 kg/m2 (aRR 2.17, 95% CI 2.15-2.19) compared with BMI 18.5-24.9 kg/m2; and pregestational diabetes (aRR 1.54, 95% CI 1.51-1.57) were all associated with increased risk. Risk factors allowed stratification of patients into high-risk versus low-risk groups. The NTSV caesarean rate was 37.9% in women who had one or more of the following characteristics: age ≥35 years, BMI ≥30 kg/m2 or pregestational diabetes. In comparison, the NTSV caesarean rate was 20.8% among women without any of these three risk factors (P < 0.01). CONCLUSION: Among NTSV births, BMI, maternal age and medical conditions are important risk factors for caesarean delivery.

Trends in operative vaginal delivery, 2005-2013: a population-based study.

OBJECTIVE: The objectives of this study were to determine temporal trends in forceps and vacuum delivery and factors associated with operative vaginal delivery. DESIGN: Retrospective cohort. SETTING: Population-based study of US birth records. POPULATION: US births from 2005 to 2013. METHODS: This study evaluated forceps and vacuum extraction during vaginal delivery in live-born, non-anomalous singleton gestations from ≥ 36 to < 42 weeks of gestation. The primary outcomes were vacuum, forceps and overall operative delivery. Obstetric, medical and demographic characteristics associated with operative vaginal delivery were analysed. Multivariable logistic regression models were developed to determine factors associated with forceps/vacuum use. RESULTS: A total of 22 598 971 vaginal deliveries between 2005 and 2013 were included in the analysis. In all, 1 083 318 (4.8%) were vacuum-assisted and 237 792 (1.1%) were by forceps. Both vacuum and forceps deliveries decreased over the study period; vacuum deliveries decreased from 5.8% in 2005 to 4.1% in 2013, and forceps deliveries decreased from 1.4% to 0.9% during the same period. The adjusted odds ratio for forceps delivery was 0.70 (95% CI 0.69-0.72) in 2013 with 2005 as a reference. For vacuum delivery the odds ratio was 0.68 (95% CI 0.67-0.69) comparing the same years. CONCLUSION: Forceps and vacuum deliveries decreased during the study period. Low rates of operative delivery pose a challenge for resident education and may limit the degree to which women have access to alternatives to caesarean delivery. Initiatives that allow future generations of obstetricians to develop expertise in performing operative deliveries in the setting of decreased volume are an urgent resident education priority. TWEETABLE ABSTRACT: Forceps and vacuum delivery decreased significantly in the USA from 2005 to 2013.

Infant mortality in the United States.

The infant mortality rate (IMR) of 6.0 per 1000 live births in the United States in 2013 is nearly the highest among developed countries. Moreover, the IMR among blacks is >twice that among whites-11.11 versus 5.06 deaths per 1000 live births.This higher IMR and racial disparity in IMR is due to a higher preterm birth rate (11.4% of live births in 2013) and higher IMR among term infants. The United States also ranks near the bottom for maternal mortality and life expectancy among the developed nations-despite ranking highest in the proportion of gross national product spent on health care. This suggests that factors other than health care contribute to the higher IMR and racial disparity in IMR. One factor is disadvantaged socioeconomic status. All of the actionable determinates that negatively impact health-personal behavior, social factors, heath-care access and quality and the environment-disproportionately affect the poor. Addressing disadvantaged socioeconomic status by improving access to quality health care and increasing social expenditures would have the greatest impact on the USA's IMR and racial disparity in IMR.

A comparison of recommendations for pharmacologic thromboembolism prophylaxis after caesarean delivery from three major guidelines.

OBJECTIVE: Guidelines for pharmacologic obstetric venous thromboembolism (VTE) prophylaxis from the American Congress of Obstetricians (ACOG), the Royal College of Obstetricians and Gynaecologists (RCOG), and the American College of Chest Physicians (Chest) vary significantly. The objective of this study was to determine the practical implications of these recommendations in terms of prophylaxis rates for a tertiary obstetric population. STUDY DESIGN: Cross-sectional. SETTING: Tertiary referral hospital. POPULATION: Patients post-operative day 1 after caesarean delivery. METHODS: This cross-sectional study evaluated rates of pharmacologic prophylaxis for women based on RCOG, ACOG, and Chest recommendations. Medical, obstetric, and demographic risk factors for thromboembolism were reviewed for individual patients. Rates of prophylaxis based on each of the guidelines with 95% confidence intervals were calculated. OUTCOME MEASURE: Recommended pharmacologic prophylaxis. RESULTS: About 293 patients were included in the analysis. Under RCOG guidelines, 85.0% of patients would receive post-caesarean pharmacologic prophylaxis [95% confidence interval (CI) 80.5-88.6%] compared with 1.0% of patients under ACOG guidelines (95% CI 0.3-3.0%) and 34.8% of patients under Chest guidelines (95% CI 29.6-40.4%). Caesarean during labour, obesity, advanced maternal age, pre-eclampsia, and multiple gestation were among the most commonrisk factors. CONCLUSION: Recommended prophylaxis differed significantly. Under ACOG recommendations a small minority of patients would receive prophylaxis, whereas under RCOG recommendations a large majority of patients would receive low-molecular-weight heparin. Given the large differences in prophylaxis rates for post-caesarean thromboprophylaxis based on different guidelines, further research is urgently needed to compare the risks and benefits of recommendations. TWEETABLE ABSTRACT: Recommendations from major society guidelines for post-caesarean thromboprophylaxis differ greatly.

Indications for caesarean sections at ≥34 weeks among nulliparous women and differential composite maternal and neonatal morbidity.

OBJECTIVE: To compare composite maternal and neonatal morbidities (CMM, CNM) among nulliparous women with primary indications for caesarean section (CS) as acute clinical emergency (group I; ACE), non-reassuring fetal heart rate (group II) and arrest disorder (group III). DESIGN: A multicentre prospective study. SETTING: Nineteen academic centres in the USA, with deliveries in 1999-2002. POPULATION: Nulliparous women (n = 9829) that had CS. METHODS: Nulliparous women undergoing CS for three categories of indications were compared using logistic regression model, adjusted for five variables. MAIN OUTCOME MEASURES: CMM was defined as the presence of any of the following: intrapartum or postpartum transfusion, uterine rupture, hysterectomy, cystotomy, ureteral or bowel injury or death; CNM was defined as the presence of any of the following: umbilical arterial pH <7.00, neonatal seizure, cardiac, hepatic, renal dysfunction, hypoxic ischaemic encephalopathy or neonatal death. RESULTS: The primary reasons for CS were ACE in 1% (group I, n = 114) non-reassuring FHR in 29% (group II; n = 2822) and failed induction/dystocia in the remaining 70% (group III; n = 6893). The overall risks of CMM and CNM were 2.5% (95% confidence intervals, CI, 2.2-2.8%) and 1.9% (95% CI 1.7-2.2), respectively. The risk of CMM was higher in group I than in group II (RR 4.1, 95% CI 3.1, 5.3), and group III (RR 3.2, 95% CI 2.7, 3.7). The risk of CNM was also higher in group I than in group II (RR 2.8, 95% CI 2.3, 3.4) and group III (RR 14.1, 95% CI 10.7, 18.7). CONCLUSIONS: Nulliparous women who have acute clinically emergent caesarean sections are at the highest risks of both composite maternal and neonatal morbidity and mortality.

Maintaining quality assurance for sonographic nuchal translucency measurement: lessons from the FASTER Trial.

OBJECTIVE: To evaluate nuchal translucency measurement quality assurance techniques in a large-scale study. METHODS: From 1999 to 2001, unselected patients with singleton gestations between 10 + 3 weeks and 13 + 6 weeks were recruited from 15 centers. Sonographic nuchal translucency measurement was performed by trained technicians. Four levels of quality assurance were employed: (1) a standardized protocol utilized by each sonographer; (2) local-image review by a second sonographer; (3) central-image scoring by a single physician; and (4) epidemiological monitoring of all accepted nuchal translucency measurements cross-sectionally and over time. RESULTS: Detailed quality assessment was available for 37 018 patients. Nuchal translucency measurement was successful in 96.3% of women. Local reviewers rejected 0.8% of images, and the single central physician reviewer rejected a further 2.9%. Multivariate analysis indicated that higher body mass index, earlier gestational age and transvaginal probe use were predictors of failure of nuchal translucency measurement and central image rejection (P = 0.001). Epidemiological monitoring identified a drift in measurements over time. CONCLUSION: Despite initial training and continuous image review, changes in nuchal translucency measurements occur over time. To maintain screening accuracy, ongoing quality assessment is needed.

First- and second-trimester Down syndrome screening markers in pregnancies achieved through assisted reproductive technologies (ART): a FASTER trial study.

OBJECTIVE: To determine whether first- and second-trimester Down syndrome screening markers and screen-positive rates are altered in pregnancies conceived using assisted reproductive technologies (ARTs). METHODS: ART pregnancies in the multicenter FASTER trial were identified. Marker levels were evaluated for five types of ART: in vitro fertilization with ovulation induction (IVF-OI), IVF with OI and egg donation (IVF-OI-ED), IVF with ED (IVF-ED), and intrauterine insemination with OI (IUI-OI) or without OI (IUI). Each group was compared to non-ART controls using Mann-Whitney U analysis. RESULTS: First-trimester marker levels were not significantly different between ART and control pregnancies, with the exception of reduced PAPP-A levels in the IUI-OI group. In contrast, second-trimester inhibin A levels were increased in all ART pregnancies, estriol was reduced and human chorionic gonadotropin (hCG) was increased in IVF and IUI pregnancies without ED, and alpha-fetoprotein (AFP) was increased in ED pregnancies. Second-trimester screen-positive rates were significantly higher than expected for ART pregnancies, except when ED was used. CONCLUSIONS: These data show that ART significantly impacts second-, but not first-, trimester markers and screen-positive rates. The type of adjustment needed in second-trimester screening depends on the particular type of ART used.

Maternal and neonatal outcome of 100 consecutive triplet pregnancies.

The objective of this study is to determine the maternal and neonatal outcome of a large group of triplet gestations. A retrospective review of 100 triplet gestations managed and delivered between January 1992 and September 1999 by a single perinatal group is examined. These pregnancies were managed on an outpatient basis. Prophylactic interventions were not utilized. Ninety-six percent of the pregnancies had at least one complication, with preterm labor the most common. The median gestational age at delivery was 33 weeks (range 20.4 to 37, SD 4.1 weeks) with 14% of pregnancies delivering prior to 28 weeks' gestation. The corrected perinatal mortality rate was 97/1000. Minimal long-term morbidity was seen with delivery after 27 weeks' gestation. Pregnancy outcome did not vary with birth order or mode of conception. Triplet pregnancy is associated with a high rate ofantenatal complications. Favorable neonatal outcome can be obtained without the use of prophylactic interventions.

Isolated clubfoot diagnosed prenatally: is karyotyping indicated?

OBJECTIVE: To evaluate the appropriateness of fetal karyotyping after prenatal sonographic diagnosis of isolated unilateral or bilateral clubfoot. METHODS: We retrospectively reviewed a database of fetal abnormalities diagnosed by ultrasound at a single tertiary referral center from July 1994 to March 1999 for cases of unilateral or bilateral clubfoot. Fetuses who had additional anomalies diagnosed prenatally, after targeted sonographic fetal anatomy surveys, were excluded. Outcome results included fetal karyotype diagnosed by amniocentesis, or newborn physical examination by a pediatrician. RESULTS: During the 5-year period, 5,731 fetal abnormalities were diagnosed from more than 27,000 targeted prenatal ultrasound examinations. There were 51 cases of isolated clubfoot. The mean maternal age at diagnosis was 30.5 years. The mean gestational age at diagnosis was 21.6 weeks. Twenty-three of the women (45%) were at increased risk of fetal aneuploidy, on the basis of advanced maternal age or abnormal maternal serum screening. Six women (12%) had positive family histories of clubfoot; however, no cases of aneuploidy were found by fetal karyotype evaluation or newborn physical examination. All cases of clubfoot diagnosed prenatally were confirmed at newborn physical examination, and no additional malformations were detected. CONCLUSION: After prenatal diagnosis of isolated unilateral or bilateral clubfoot, there appeared to be no indication to offer karyotyping, provided that a detailed sonographic fetal anatomy survey was normal and there were no additional indications for invasive prenatal diagnoses.

First-trimester screening for aneuploidy: research or standard of care?

First-trimester screening for Down syndrome has been proposed as a significant improvement with respect to second-trimester serum screening programs, the current standard of care, because of apparently higher detection rates and an earlier gestational age at diagnosis. First-trimester nuchal translucency on ultrasonography forms the basis of this new form of screening, although studies of its efficacy have yielded widely conflicting results, with detection rates ranging from 29% to 91%. Studies of first-trimester serum screening with measurements of pregnancy-associated plasma protein A and free beta-human chorionic gonadotropin serum concentrations have been much more consistent, with Down syndrome detection rates of 55% to 63% at a 5% false-positive rate. The combination of first-trimester ultrasonographic and serum screening has the potential to yield a Down syndrome detection rate of 80% at a 5% false-positive rate, although this approach has not been adequately studied. There have been no studies performed to date to directly compare the performance of first-trimester and second-trimester methods of screening. Two major trials are underway that will address this issue, one in the United Kingdom and one in the United States. Until the results of these trials are available, the current standard of care with respect to Down syndrome screening should not be changed, and first-trimester screening should remain investigational.

Congenital heart disease: the impact of delivery in a tertiary care center on SNAP scores (scores for neonatal acute physiology).

OBJECTIVE: It has been hypothesized that delivery in a tertiary care center might improve the clinical condition and outcome of infants born with congenital heart disease. The purpose of this study was to determine the effect of delivery in a tertiary care center on SNAP scores (scores for neonatal acute physiology) of infants admitted to the neonatal intensive care unit with major structural cardiac defects. STUDY DESIGN: This retrospective cohort study included 195 infants with major congenital heart disease admitted to the neonatal intensive care unit at the New England Medical Center between July 1, 1992, and June 30, 1998. SNAP scores were abstracted from the medical record. The values of 97 neonates with major cardiac defects born at the New England Medical Center were compared with those of 98 neonates transferred to our center after delivery in a community setting. A 2-tailed Student t test for independent samples was used to compare the mean SNAP scores between the 2 cohorts. RESULTS: The SNAP scores for infants with major cardiac defects who were born at the New England Medical Center ranged from 0 to 41, with a mean of 10.6 +/- 8.8. The values for infants with congenital heart disease who were transferred to our center after birth in community-based hospitals ranged from 0 to 34, with a mean of 11.1 +/- 7.0. There was no significant difference between the 2 populations (P =.646). A comparison of the mean SNAP scores of infants with prenatally diagnosed disease who were delivered at our center versus infants with postnatally diagnosed disease who were delivered in community hospitals was also statistically not significant (P =.824). CONCLUSION: Delivery in a tertiary care center does not improve SNAP scores of infants with major structural cardiac defects.

Anomalies peculiar to multiple gestations.

Congenital anomalies occur twice as often in twin pregnancies as in singletons. In addition to the large range of structural malformations that are described in singleton fetuses, multiple gestations are at risk for additional anomalies that are unique to the twinning process. These unique anomalies include twin-twin transfusion syndrome, twin-reversed-arterial-perfusion syndrome, and conjoined twinning. This article reviews and describes each of these unique abnormal conditions in detail.

Impact of gestational age at delivery of the economics of triplet pregnancy.

OBJECTIVE: To establish the charges associated with triplet pregnancies managed at a single tertiary center, over a 5-year time period, and to evaluate the impact of prematurity on these charges. METHODS: All triplet pregnancies that reached at least 20 weeks gestation and received prenatal and neonatal care at our center from 1992 to 1996 were included. Charges for these mothers and neonates were extracted from two separate hospital billing computer systems, encompassing all inpatient, outpatient, technical, and professional charges. Linear regression was used to evaluate the relationship between gestational age at delivery and total charges. RESULTS: Fifty-five triplet pregnancies were included, resulting in the admission of 149 liveborn neonates. The median gestational age at delivery was 32.1 weeks. The mean charges per triplet mother were: $6,899 (professional), $3,959 (hospital outpatient), and $32,686 (hospital inpatient). The mean charges per neonatal sibling set were: $20,107 (professional) and $124,163 (hospital inpatient). The mean charges per complete triplet pregnancy was $187,814 (maternal plus neonatal). There was a significant inverse relationship between gestational age at delivery and total charges per triplet family, with a decrease of $16,584 for each additional gestational week reached (P = 0.006). CONCLUSIONS: Triplet pregnancy charges averaged almost $190,000 each, which does not include charges associated with assisted reproductive technologies. These charges are almost all related to the expense of prolonged neonatal intensive care, and are significantly related to the gestational age at delivery. Efforts at containing these costs should focus on reducing the incidence of multiple gestation and preventing prematurity.

Latent class analysis applied to patterns of fetal sonographic abnormalities: definition of phenotypes associated with aneuploidy.

The aim of the present study was to generate different latent variables that classify the major chromosome aneuploidies using frequency and patterns of fetal sonographic abnormalities in a large database. A total of 1867 fetuses with sonographic abnormalities recorded in a database at New England Medical Center from January 1995 to March 1998 were available for the statistical analysis. Included within this group were 61 aneuploid fetuses, including 11 with 45,X, 30 with trisomy 21, 14 with trisomy 18 and 6 with trisomy 13, 40 structural malformations and/or sonographic markers were detected in these 61 aneuploid fetuses. The ability of malformations and sonographic markers to generate different groups of phenotypes was evaluated by means of latent class analysis, using the 61 affected cases. Four different classes were generated with the hypothetical assumption that each of them could satisfactorily identify a respective fetal aneuploidy represented in the study group. Among 40 fetal malformations and/or sonographic markers, the most important findings in generating specific karyotypic groups were cystic hygroma (class 1), duodenal atresia (class 2), holoprosencephaly (class 3) and omphalocele (class 4), respectively. Accuracy of the classification was 72 per cent for Turner syndrome (class 1), 74 per cent for Down syndrome (classes 1 and 2), 88 per cent for trisomy 13 (class 3) and 93 per cent for trisomy 18. The frequency of associated malformations detected sonographically can help to define a phenotype that is likely to be representative of a specific aneuploidy. Before the definitive karyotype is available or, in cases in which patients refuse an invasive prenatal diagnostic procedure, this may improve antenatal clinical management.

Antenatal therapy of Smith-Lemli-Opitz syndrome.

OBJECTIVES: Smith-Lemli-Opitz syndrome (SLOS) is a recessively inherited disorder caused by an inborn error of cholesterol metabolism that results in deficiency of cholesterol and accumulation of the cholesterol precursor, 7-dehydrocholesterol (DHC) and its epimer, 8-DHC. Affected patients present with congenital anomalies, growth restriction, and mental retardation. Postnatal treatment with cholesterol supplementation has been shown to improve plasma sterol levels and has resulted in improved growth and development in many patients. We hypothesized that prenatal supplementation of cholesterol could potentially arrest some of the adverse consequences of cholesterol deficiency at an earlier stage of development. METHODS: SLOS was diagnosed in the third trimester in a fetus initially identified by sonography with intrauterine growth restriction and ambiguous genitalia and confirmed by elevated levels of 7- and 8-DHC in amniotic fluid. Antenatal supplementation of cholesterol was provided by fetal intravenous and intraperitoneal transfusions of fresh frozen plasma (cholesterol level = 219 mg/dl). RESULTS: The in utero transfusions resulted in increased levels of fetal cholesterol, as measured in blood samples obtained by cordocentesis. In addition, fetal red cell mean corpuscular volume rose, which further indicated that the exogenous cholesterol was incorporated into the fetal erythrocytes. CONCLUSIONS: Antenatal treatment of SLOS by cholesterol supplementation is feasible and results in improvement in fetal plasma cholesterol levels and fetal red cell volume. SLOS may be added to the growing list of human genetic disorders for which prenatal diagnosis is available and therapeutic intervention may be possible.

Cardiac dysfunction in twin-twin transfusion syndrome: a prospective, longitudinal study.

OBJECTIVE: To use serial echocardiography to evaluate prospectively the cardiac dysfunction in twin-twin transfusion syndrome and determine its clinical course and outcome. METHODS: Twin pregnancies presenting in the second trimester with sonographic evidence of twin-twin transfusion syndrome were managed with therapeutic reduction amniocenteses. Gestational age at diagnosis and delivery, number of amniocenteses performed, volume of amniotic fluid withdrawn, placentation, birth weight, hemoglobin at delivery, and perinatal outcome were recorded. Serial fetal echocardiography was carried out in a single tertiary center. Echocardiographic assessments included cardiac anatomy, chamber size, cardiothoracic ratio, interventricular septal thickness, ventricular systolic function, and the presence and severity of atrioventricular valve regurgitation. Postnatal echocardiograms were obtained on the surviving twins. RESULTS: Twelve cases of twin-twin transfusion syndrome were evaluated with serial echocardiography. Evidence of cardiac dysfunction was present prenatally in 10 recipient twins. All of the donor twins had normal fetal echocardiographic assessments. The most common abnormalities detected prenatally in recipient twins were decreased ventricular function, tricuspid regurgitation, and cardiac chamber enlargement. A deterioration of cardiac function was observed in seven recipient twins with increasing gestational age. Four of the eight surviving recipient twins had persistent postnatal echocardiographic abnormalities on follow-up examinations after the first 28 days of life. CONCLUSION: Prenatal cardiac dysfunction is common in recipient twins and can be transient, progressive, or persistent beyond the neonatal period.

Cost issues surrounding the use of computerized telemedicine for obstetric ultrasonography.

OBJECTIVE: The purpose of this study was to describe the cost implications of converting an established videotape review network for obstetric ultrasonography to one based on telemedicine technology. DESIGN: Retrospective review of fixed and non-fixed costs associated with interpreting obstetric ultrasound examinations using both videotape and telemedicine transmission. SUBJECTS: A network of three community offices transmitting 600 obstetric ultrasound examinations per month to a central tertiary level facility. METHODS: Sonographers at the community offices record ultrasound examinations onto videotape, which are then sent by courier to a central facility for interpretation. At the completion of this videotaped examination, sonographers repeat the ultrasound scan while transmitting real-time images over a telemedicine link to the central facility. Costs associated with the videotape review technique that can be avoided by converting to telemedicine interpretation were derived and compared with the fixed and non-fixed costs associated with establishing the telemedicine network. RESULTS: For this network, the fixed costs for establishing telemedicine are $101,750. Monthly non-fixed cost savings by eliminating videotape review include $1620 to $2700 for printing still images, $1200 for courier charges and $7000 for fewer repeat ultrasound examinations. Monthly non-fixed costs for the telemedicine network are $2415. Net monthly savings in non-fixed costs for a telemedicine network are therefore $7405 to $8585, which may pay for the initial fixed costs in 12 to 14 months. CONCLUSIONS: The high cost of a telemedicine network may be offset by possible savings in non-fixed costs compared with alternative systems for interpreting obstetric ultrasonography.