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.

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.

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.

Factors affecting fellowship satisfaction, thesis completion, and career direction among maternal-fetal medicine fellows.

OBJECTIVE: To determine fellowship satisfaction through a survey of maternal-fetal medicine fellows. METHODS: We constructed a survey using multiple choice, Likert scale, ordinal, and categorical scale questions. The questions focused on faculty involvement, mentorship, research time and productivity, education, fellowship selection, ultimate goals of fellows, and satisfaction. We sent the survey in two mailings to all maternal-fetal medicine fellows during April and May 1996. RESULTS: One hundred thirty-eight surveys were mailed, and 136 were returned (98.5% return rate). Twenty-seven percent of fellows did not believe they would complete their thesis by the end of their fellowship. No statistically significant relationship was noted between the fellows' predicted thesis completion and the availability of funding, support for statistical analysis, the presence of animal research facilities, age, number of dependents, or year of fellowship. The presence of a mentor on the maternal-fetal medicine faculty increased the likelihood of thesis completion from 52.3% to 83.5% (P < .001). Similarly, the presence of a faculty advisor increased the likelihood of thesis completion from 58.9% to 83.5% (P = .001). Thirty-two percent of the respondents did not have a mentor on the faculty, and 41% did not have a faculty advisor. Forty percent indicated that they were too involved in clinical pursuits to perform research. This group was significantly more likely to believe that their theses would not be completed (63% versus 80%, P = .029). Overall, 22% of the fellows would not recommend their fellowships. Fellows with a mentor (88.2% versus 55.8%; P < .001) or faculty advisor (87.3% versus 64.9%; P = .002) were more likely than those without to recommend their fellowship. CONCLUSION: A mentor or faculty advisor plays a significant role in the training of maternal-fetal medicine fellows and is associated with a higher incidence of satisfaction with the fellowship program, thesis completion, and entrance into academic practice.

Gender differences in twin-twin transfusion syndrome.

OBJECTIVE: To determine whether there is a gender discrepancy in severe twin-twin transfusion syndrome. METHODS: All cases of twin-twin transfusion syndrome evaluated between 1989 and 1996 were reviewed retrospectively. The following sonographic criteria were used: a single placenta, a thin membrane, the same gender, a combination of polyhydramnios-oligohydramnios, a stuck twin, and an estimated weight discordance exceeding 20%. At least five of six sonographic criteria were required for inclusion in the study. Only severe cases, which were defined as early onset (before 30 weeks' gestation), a combination of polyhydramnios and oligohydramnios, a stuck twin, fetal hydrops, fetal death, or the requirement of medical or invasive treatment, were included. Chorionicity was confirmed by placental examination when available. RESULTS: Thirty-seven twin pregnancies met the above criteria, of which 33 (89%) twin pairs were female. The median gestational age at presentation was 19 weeks (range, 15-29; standard deviation, 5.6). A single placenta, thin membrane, same gender, and polyhydramnios-oligohydramnios were present in every case. A stuck twin was noted in 34 of 37 cases (92%), and a growth discordance exceeding 20% was present in 26 of 36 (72%). Placental pathology, which was available in 31 (84%) cases, confirmed a monochorionic placentation in 29. Twenty-five (68%) cases had reduction amniocentesis, two were treated with indomethacin, one underwent a cord ligation, and in four cases, fetal death occurred before treatment was instituted. CONCLUSION: There is a significant female preponderance in pregnancies complicated by severe twin-twin transfusion syndrome. The reasons for this are nuclear, but they may be related to either placental or fetal gender-specific differences affecting a subset of monochorionic twin pregnancies.

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.

Lumbar disk disease in pregnancy.

BACKGROUND: Lumbar disk herniation is rare in pregnancy. We report on three pregnant women with this disorder seen over 2 years. CASES: Three women were seen with progressive back pain, paresthesias, and urinary retention. In all three cases, magnetic resonance imaging confirmed the diagnosis. All failed conservative treatment and required surgery. All did well postoperatively, with improvement of symptoms and delivery at or near term. CONCLUSION: Lumbar disk herniation should be considered in pregnant women presenting with considerable back or leg pain. Magnetic resonance imaging is a useful diagnostic tool. Most patients can be treated conservatively, but those with incapacitating pain, progressive neurologic deficits, or bowel or bladder dysfunction may require surgical treatment.

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.

Acute fatty liver of pregnancy in triplet gestation.

BACKGROUND: Acute fatty liver is reported to be more common in twin than in singleton pregnancies. We report three cases of biopsy-proven acute fatty liver in triplet gestations. CASES: In all three cases of acute fatty liver complicating triplet pregnancies, the presenting features were vague abdominal complaints with elevated hepatic aminotransferase levels. A liver biopsy was performed in each case, and cesareans were performed immediately after the diagnosis was confirmed histologically. Clinical resolution occurred in all cases, and all infants did well in the neonatal period. CONCLUSION: Patients with triplet gestations should be monitored closely for the early signs of acute fatty liver. Triplet gestations may contribute to the onset of acute fatty liver by further stressing the fatty acid oxidation capabilities of the susceptible woman.

Prolonged labor in nulliparas: lessons from the active management of labor.

OBJECTIVE: To define factors causing prolonged labor in nulliparous women undergoing active management of labor. METHODS: We included all nulliparas delivered during 1990-1994 with spontaneous onset of labor lasting more than 12 hours, singleton gestation, cephalic presentation, and labor at greater than 37 weeks. Each patient was matched with the next nulliparous woman who delivered with a labor lasting less than 12 hours and who fulfilled the same inclusion criteria. Subjects were managed according to the previously described active management of labor protocol from The National Maternity Hospital, Dublin. RESULTS: In the 5-year period, 9018 nulliparas met inclusion criteria, with 147 (1.6%) having prolonged labor. Prolonged labor was due to inefficient uterine action in 65%, persistent occipitoposterior position in 24%, and cephalopelvic disproportion in 11% of cases. Univariate analysis showed statistically significant (P < .05) differences in maternal body mass index, cervical dilation on admission, oxytocin use, epidural use, placement of epidural at less than 2 cm of dilation, and birth weight between these study groups. On multivariate conditional logistic regression analysis, the following were significant independent predictors for having a prolonged labor (odds ratios with 95% confidence intervals presented): 3.1 (1.3-7.3) for cervical dilation less than 2 cm on admission, 42.7 (7.5-242.0) for early epidural placement, 5.1 (1.9-13.7) for epidural placement at greater than or equal to 2 cm, and 10.2 (3.6-29.4) for birth weight greater than 4000 g. CONCLUSION: Less-advanced cervical dilation on admission and epidural use, especially when placed early, are strongly associated with prolonged labor.

Outcome of twin gestations complicated by a single anomalous fetus.

OBJECTIVE: To compare the outcome of twin gestations complicated by a single anomalous fetus with twin gestations with no fetal anomalies. METHODS: The study included all patients with twin gestations diagnosed with a fetal anomaly in one fetus during 1990-1994, and excluded twin gestations with anomalies in both fetuses. The control twin group was composed of all other normal twin pregnancies followed and delivered at our center in the preceding 2 years. RESULTS: We reviewed 24 twin gestations with at least one anomalous fetus. Five cases were excluded because of anomalies in both fetuses, and a further five pregnancies had selective termination or termination of the entire pregnancy. There were 14 ongoing twin pregnancies with one anomalous fetus, and their median gestational age at diagnosis was 18 weeks (range 16-20). All twin anomalies were correctly diagnosed antenatally. Gestational age at delivery and birth weight were significantly lower for twins complicated by an anomaly compared with control twins (P = .008 and P = .001, respectively). The cesarean delivery and perinatal mortality rates of twin pregnancies with anomalies were significantly higher than those of normal twins (P = .01 and P < .001, respectively). CONCLUSION: The presence of a single anomalous fetus in a twin gestation significantly increases the risk of preterm delivery compared with nonanomalous twin gestations.

Validation of first-trimester telemedicine as an obstetric imaging technology: a feasibility study.

OBJECTIVE: To establish whether first-trimester obstetric ultrasonography interpreted by a live video telemedicine link is comparable to an established videotape review network in a low-risk patient population. METHODS: An integrated services digital network was established from three satellite offices to our central prenatal diagnostic center. All patients had a sonographic evaluation of the uterus, adnexa, and gestational sac recorded onto videotape by a trained sonographer. A live, interactive video telemedicine link was established, and a perinatologist directed the sonographer through the scan. Subsequently, a different perinatologist, blinded to the telemedicine interpretation, reviewed the original videotaped examination. The reports generated from both modalities then were compared by means of a score of 12 sonographic characteristics. RESULTS: The first 100 patients were included. The mean gestational age (+/-standard deviation) was 8.9 +/- 2.3 weeks (range 5.7-14.4), and the mean duration for telemedicine scans was 7.8 +/- 2.9 minutes (range 3.8-20.1). Telemedicine and videotape review scores were the same in 95 cases, and the final diagnosis was identical in 98 cases. This study had 80% power to detect a 10% difference in diagnosis at a significance level of .05. The ability to detect abnormalities was equivalent using both systems. CONCLUSION: The interpretation of first-trimester obstetric ultrasonography using live video telemedicine is equivalent to a system of videotape review. Obstetric telemedicine may prove to be a useful tool for providing sonographic imaging for low-risk obstetric patients.

Neonatal morbidity and mortality associated with triplet pregnancy.

OBJECTIVE: To compare neonatal morbidity and mortality in a large cohort of triplet pregnancies with singleton and twin neonates managed at a single tertiary center over a short time. METHODS: Records from all triplet pregnancies managed and delivered from 1992 to 1996 were reviewed for neonatal outcome data. Pregnancies delivered before 20 weeks' gestation and neonates with lethal congenital anomalies were excluded. The comparison group comprised all singleton and twin neonates managed in the same neonatal intensive care unit (NICU) during the same period. RESULTS: During the 5-year period, 55 triplet pregnancies and their resulting 165 neonates were managed and delivered at this center. Their outcomes were compared with those of 959 singleton and 357 twin neonates born at similar gestational ages. The median gestational age at delivery for triplets was 32.1 weeks, and 149 of the 165 infants were admitted. Sixteen triplet neonates were not admitted to our neonatal intensive care unit, 12 because of previable gestational age, three because of stillbirth, and one because of a lethal congenital anomaly. The crude perinatal mortality rate in triplets was 121 per 1000 births, and there was no significant difference in outcome based on triplet birth order. There were no significant differences in survival rates between singleton, twin, and triplet neonates, with an overall neonatal survival of 95%, 95%, and 97%, respectively. The only significant differences in morbidity were an increased incidence of mild intraventricular hemorrhage (relative risk [RR] 6.20; 95% confidence interval [CI] 2.64, 14.61), mild retinopathy of prematurity (RR 20.05; 95% CI 3.59, 111.79), and severe retinopathy of prematurity (RR 46.69; 95% CI 6.25, 348.85) in triplets compared with singletons, and severe retinopathy of prematurity (RR 6.83; 95% CI 1.24, 37.56) in triplets compared with twins. CONCLUSION: When stratified by gestational age, triplet neonates delivered at 24-34 weeks' gestation have similar outcomes as singleton and twin neonates, with the only clinically significant difference being an increased incidence of retinopathy of prematurity in triplets.

Prenatal diagnostic procedures.

Invasive prenatal diagnostic techniques such as fetal skin sampling, fetal liver biopsy, and fetal muscle biopsy are now reserved for the diagnosis of congenital disorders not amenable to diagnosis using amniocentesis or CVS. In the next few years, many of these conditions will become detectable by DNA analysis, and the need for these procedures will decline even further.

Syndromes in twins.

There is a higher incidence of perinatal mortality and morbidity in twins than in singleton pregnancies. The main reason for this increase is the higher incidence of preterm delivery in twins. There are special conditions unique to twins that also contribute to this increased perinatal morbidity and mortality. These conditions include monoamniotic twins, congenital anomalies unique to twins, ie, conjoined twins and acardia, intrauterine fetal demise, and twin-to-twin transfusion syndrome. These conditions are the subject of this review. The prenatal determination of chorionicity is discussed first, because this assessment is key to the diagnosis and management of many of these conditions.