Prenatal Diagnosis in Twin Gestations Vink, Joy, MD; Wapner, Ronald, MD; D'Alton, Mary E., MD
Seminars in perinatology,
06/2012, Letnik:
36, Številka:
3
Journal Article
Recenzirano
Twin gestations face an increased risk of structural abnormalities compared with singleton gestations, as well as an increased risk of aneuploidy. Accordingly, there is a need for accurate prenatal ...diagnosis of fetal genetic disorders and structural anomalies in twin gestations. Given the increased risk of congenital anomalies, a detailed sonographic survey of fetal anatomy is recommended in the early second trimester of twin gestations. In addition, fetal echocardiography should be considered in monochorionic twin gestations and in dichorionic twin pregnancies conceived using assisted reproductive technologies given the increased risk of congenital heart disease in these populations. Although first- and second-trimester aneuploidy screening in twin gestations is available, screening is less accurate than in singleton gestations. Invasive prenatal diagnosis in twin pregnancies is associated with a risk of pregnancy loss that is higher than the baseline risk of loss among twin gestations. Precise procedure-related loss rates in twin gestations undergoing chorionic villus sampling or amniocentesis, however, remain unclear because of methodological differences between published studies investigating diagnostic procedures in twins.
Pulmonary embolus in pregnancy Donnelly, Jennifer C., MD; D'Alton, Mary E., MD
Seminars in perinatology,
08/2013, Letnik:
37, Številka:
4
Journal Article
Recenzirano
Abstract Venous thromboembolism remains in the top three leading causes of maternal death in the US, representing 10.2% of pregnancy-related deaths. Risk of developing a pulmonary embolus appears to ...increase throughout pregnancy, with a peak in incidence in the early postpartum period. Overall the incidence of VTE is 0.6–1.8 VTEs per 1000 deliveries. Diagnosis and management of pulmonary embolus can prove challenging, but the aim should be to optimize maternal outcome while minimizing hemorrhagic complications. Low-molecular-weight heparin is a safe and effective treatment for the majority of cases of pregnancy-related pulmonary embolus.
Objective The purpose of this study was to compare strategies for delivery timing of uncomplicated monochorionic diamniotic twin pregnancies. Study Design A decision tree compared 9 strategies that ...included scheduled delivery between 32 and 38 weeks' gestation, with or without confirmation of fetal lung maturity. Outcomes in the model included fetal death, infant death, respiratory distress syndrome, mental retardation, and cerebral palsy. Results A scheduled delivery at 38 weeks' gestation was the preferred strategy, which resulted in the highest quality adjusted life years under base-case assumptions. Decreased, but comparable, quality adjusted life years estimates resulted from scheduled deliveries at 36 and 37 weeks' gestation, with or without amniocentesis. Sensitivity analyses demonstrated that the optimal gestational age for delivery was always ≥36 weeks' gestation. Conclusion This decision analysis suggests that, for women with uncomplicated monochorionic twins, delivery between 36 and 38 weeks' gestation is the preferred strategy for timing of delivery.
Objective To develop and evaluate a method of estimating patient-specific risk for fetal loss by combining maternal characteristics with serum markers. Study Design Data were obtained on 36,014 women ...from the FaSTER trial. Separate likelihood ratios were estimated for significant maternal characteristics and serum markers. Patient-specific risk was calculated by multiplying the incidence of fetal loss by the likelihood ratios for each maternal characteristic and for different serum marker combinations. Results Three hundred eighteen women had fetal loss < 24 weeks (early) and 103 > 24 weeks (late). Clinical characteristics evaluated included maternal age, body mass index, race, parity, threatened abortion, previous preterm delivery, and previous early loss. Serum markers studied as possible predictors of early loss included first-trimester pregnancy-associated plasma protein A and second-trimester alpha-fetoprotein, and unconjugated estriol. A risk assessment for early loss based on all of these factors yielded a 46% detection rate, for a fixed 10% false-positive rate, 39% for 5% and 28% for 1%. The only significant marker for late loss was inhibin A. The detection rate was 27% for a fixed 10% false-positive rate and only increased slightly when clinical characteristics were added to the model. Conclusion Patient-specific risk assessment for early fetal loss using serum markers, with or without maternal characteristics, has a moderately high detection. Patient-specific risk assessment for late fetal loss has low detection rates.
Growth abnormalities which include intrauterine growth restriction and weight discordance between twins are common in pregnancies complicated by multiple gestations and may be associated with poor ...perinatal outcomes. Knowledge of chorionicity is paramount when managing a multiple pregnancy. Monochorionic twins are at greater risk than dichorionic twins for growth issues, which may result in long-term complications including adverse neurological sequelae for the offspring. The purpose of the following article is to define normal and abnormal growth in multiples. In addition, the management of growth abnormalities in relationship to chorionicity will be discussed.
Objective The purpose of this study was to examine how closely hypothyroidism management in the general pregnancy population satisfies recently issued guidelines and to determine whether improvements ...are indicated. Study Design This was an observational study in which women at 5 recruitment centers in the first- and second-trimester evaluation of risk for aneuploidy trial allowed the use of sequentially obtained first- and second-trimester sera for additional research. Three hundred eighty-nine women had hypothyroidism by self-report. Thyroid-related measurements were performed on all samples between July 2004 and May 2005. Results Forty-three percent of the thyroid-stimulating hormone (TSH) values are at or above recently recommended guidelines in the first trimester (2.5 mU/L), as opposed to 33% of the values in the second trimester (3.0 mU/L). Twenty percent of the TSH values are at or above a less restrictive 98th percentile of normal in the first trimester, as opposed to 23% of the values in the second trimester. Mean TSH levels are higher in women with antibodies. Free thyroxine values are unremarkable. Conclusion Future strategies should focus on more effectively treating women with hypothyroidism who have persistently elevated TSH values.
Mothers should be counseled that the most concerning risks related to maternal request cesarean delivery are neonatal respiratory morbidity and those that may affect the mother's future reproductive ...health, including life-threatening conditions, such as placenta accreta. The literature suggests that overall risks of maternal complications with cesarean delivery on maternal request are slightly lower than a trial of vaginal delivery and are primarily driven by the avoidance of unplanned or emergent cesarean deliveries and their associated increased rate of complications. When addressing risks and benefits with patients, there are three areas of importance. First, the risks for neonatal respiratory morbidity and abnormal placentation with future pregnancies should be emphasized. Secondly, there are many areas on which studies are lacking. Finally, numerous factors can alter the risks and benefits--such as culture, maternal obesity, and provider background--and should be acknowledged.
