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Congenital bilateral renal agenesis has been considered a uniformly fatal condition. However, the report of using serial amnioinfusions followed by the live birth in 2012 and ongoing survival of a child with bilateral renal agenesis has generated hope, but also considerable controversy over an array of complex clinical and ethical concerns. To assess the ethical concerns associated with using serial amnioinfusions for bilateral renal agenesis, we assembled a multidisciplinary group to map the ethical issues relevant to this novel intervention. The key ethical issues identified were related to 1) potential risks and benefits, 2) clinical care compared with innovation compared with research, 3) counseling of expectant parents, 4) consent, 5) outcome measures, 6) access and justice, 7) conflicts of interest, 8) effects on clinicians, 9) effects on institutions, and 10) long-term societal implications. These ethical issues should be addressed in conjunction with systematic efforts to examine whether this intervention is safe and effective. Future work should capture the experiences of expectant parents, women who undergo serial amnioinfusions, those born with bilateral renal agenesis and their families as well as clinicians confronted with making difficult choices related to it.

Doppler evaluation of the fetal ductus venosus has increased our depth of understanding of many fetal conditions. The ductus venosus has an important role in the regulation of nutrient partitioning in the fetus. Alterations in cardiac afterload, contractility compliance, intravascular volume status, and heart rate may significantly impact on the ductus venosus flow velocity waveform. Accordingly, ductus venosus Doppler is useful in the management of conditions that put the fetus at risk for cardiovascular deterioration. The application of DV Doppler in fetal growth restriction, complicated monochorionic multiple gestation, fetal hydrops, and arrhythmia are discussed in this review.

BACKGROUND Twin reversed arterial perfusion sequence is a rare complication of monochorionic twin gestations for which therapy involves the disruption of vascular anastomoses between the pump twin and acardiac twin and death of the acardius. CASE A 37-year-old woman, gravida 11 para 2, with a monochorionic twin pregnancy complicated by twin reversed arterial perfusion sequence who underwent umbilical cord occlusion at 24 weeks of gestation was admitted in preterm labor at 33 weeks of gestation. Maternal disseminated intravascular coagulation (DIC) was diagnosed and her labor was induced. She received multiple blood products to correct her coagulopathy and had an uncomplicated vaginal delivery of the viable pump twin. CONCLUSION Maternal DIC may complicate fetal death after umbilical cord occlusion.

UNLABELLED Normal fetal growth depends on the genetically predetermined growth potential and is modulated by fetal, placental, maternal, and external factors. Fetuses with intrauterine growth restriction (IUGR) are at high risk for poor short- and long-term outcome. Although there are many underlying etiologies, IUGR resulting from placental insufficiency is most relevant clinically because outcome could be altered by appropriate diagnosis and timely delivery. A diagnostic approach that aims to separate IUGR resulting from placental disease from constitutionally small fetuses and those with other underlying etiologies (e.g., aneuploidy, viral infection, nonaneuploid syndromes) needs to integrate multiple imaging modalities. In placental-based IUGR, cardiovascular and behavioral responses are interrelated with the disease severity. Ultrasound assessment of fetal anatomy, amniotic fluid volume, and growth is complementary to the Doppler investigation of fetoplacental blood flow dynamics. A diagnostic approach to IUGR combining these modalities is presented in this review. TARGET AUDIENCE Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES After completion of this article, the reader should be able to describe the development of the placental interface, to outline the mechanisms of placental insufficiency, and to list the manifestations of placental insufficiency and the tests that can be used to diagnose fetal growth restriction.

Babies who are small due to intrauterine growth restriction are at higher risk for poor perinatal and long-term outcome than those who are appropriately grown. Through multiple antenatal testing modalities a sequence of deteriorating fetal status can be documented in such cases. The nature of this compromise is best reflected by the combination of fetal biometry, biophysical profile scoring and arterial and venous Doppler. This combination accurately defines fetal states and therefore risk of stillbirth or poor transition to extrauterine life. In the preterm neonate, fetal factors, gestational age and neonatal course interact significantly to impact on short- and long-term outcomes. The potential for iatrogenic prematurity is great and ongoing appraisal of peripartum management is critical. An integrated management protocol accounting for these factors is examined in this review.

Interest in fetal intervention has become widespread in recent years. Laser therapy for the treatment of severe twin-twin transfusion alone has been the subject of more than 100 peer-reviewed articles in the past 3 years. Significant issues have arisen that affect the availability of these new therapies in the United States. Formal training fellowships have yet to be established. Questions as to the ultimate number of treatment centers that are required to provide reasonable access should be addressed. The establishment of research networks to evaluate new fetal therapies through randomized clinical trials would appear paramount to the advancement of the field.

It is likely that calcium channel blockers such as nifedipine will be increasingly used as tocolytic agents. Nifedipine, although an effective tocolytic with generally low toxicity, is reported to have cardiovascular sideeffects that could compromise both the mother and fetus. The investigators examined the acute effects of maternal nifedipine treatment on placental and fetal cerebral blood flow resistance and on fetal diastolic cardiac function. Doppler waveforms were recorded in 21 pairs of pregnant women diagnosed as having preterm labor at 24 to 34 weeks gestation and in their fetuses. The uterine arteries (UtA), umbilical artery (UA), middle cerebral arteries (MCA), and both atrioventricular valves were evaluated. Studies were repeated 3 hours after the first dose of nifedipine. The women had a median age of 29 years and were at a median of 30 weeks gestation. Their median gravidity was 2. Nifedipine treatment did not significantly alter the mother's heart rate or blood pressure. Flushing was the most common maternal aide effect related to nifedipine, present in 76% of women. The next most common effects were headache in 28.5% of the group and nausea in 14%. None of the women had tachycardia or hypotension, and liver enzymes were not elevated. On average, 31 days were gained in utero, and only 1 patient delivered within 48 hours. The mean gestational age at birth was 34.6 weeks and the mean birth weight was 2602 g. There were no changes in blood flow resistance in either the maternal or fetal compartment of the placental circulation. Neither the systolic-diastolic ratio nor the pulsatility index changed in the UtA, UA, or MCA, and the cerebroplacental ratio also was unaffected. Diastolic filling of the heart was not altered by nifedipine. There were no changes between pre- and posttreatment measurements of the E/A (E-wave/A-wave) ratio, the time-velocity integral (TVI) for either atrioventricular valve, or the product of TVI X fetal heart rate. These observations mean that women in preterm labor with otherwise normal pregnancies generally tolerate nifedipine loading well. Any transitory effects on the umbilical circulation resolve rapidly. Maternal nifedipine therapy also appears to be safe for the fetus. The choice of a tocolytic agent need not be based solely on clinical efficacy.