Comprehensive assessment of fetal wellbeing: which Doppler tests should be performed?

PURPOSE OF REVIEW: Doppler applications in pregnancy are expanding exponentially. Flow velocity waveforms provide important information 12 weeks to term, from maternal vessels, placental circulation and fetal systemic vessels, with implications for both mother and fetus. As applications proliferate, awareness of the complexity of fetal and placental circulations, in normal pregnancy and in sequential responses to compromise, has also grown. The necessary data are now available to establish core values in Doppler evaluation for at-risk pregnancies. RECENT FINDINGS: Uterine arteries depict maternal vascular effects of the invading placenta, predicting the frequency and severity of pre-eclampsia and intrauterine growth restriction. New evidence suggests early treatment based on this principle, significantly reduces these impacts. Umbilical artery Doppler reflects downstream placental vascular resistance, strongly correlated with intrauterine growth restriction and the multisystem effects of placental deficiency. Abnormalities are progressive, with reduction, loss, and finally a reversal of diastolic flow. When umbilical arteries become abnormal, the differentiation of fetal status requires Doppler information from systemic vessels. Middle cerebral artery changes begin when the redistribution of cardiac output reflects rising placental resistance, demonstrating 'brain sparing' when cerebrovascular dilation occurs. In the compromised intrauterine growth retarded fetus, precordial veins illustrate fetal cardiac function, changing as the respiratory status declines. This Doppler information is combined with biophysical profile scoring to determine the need for and timing of intervention. SUMMARY: Doppler evaluation of at-risk pregnancies provides crucial prognostic and diagnostic detail about placentation and fetal adaptation. What has been research detail is now becoming the standard of care, in comprehensive fetal-maternal assessment.     

Pregnancy in women with type 1 diabetes: Have the goals of St. Vincent declaration been met concerning foetal and neonatal complications?

Abstract

Objective: In 1989 the St. Vincent declaration set a five-year target for approximating outcomes of pregnancies in women with diabetes to those of the background population. We investigated and quantified the risk of adverse pregnancy outcomes in pregnant women with type 1 diabetes (T1DM) to evaluate if the goals of the 1989 St. Vincent Declaration have been obtained concerning foetal and neonatal complications.

Methods: Twelve population-based studies published within the last 10 years with in total 14?099 women with T1DM and 4?035?373 women from the background population were identified. The prevalence of four foetal and neonatal complications was compared.

Results: In women with T1DM versus the background population, congenital malformations occurred in 5.0% (2.2–9.0) (weighted mean and range) versus 2.1% (1.5–2.9), relative risk (RR)?=?2.4, perinatal mortality in 2.7% (2.0–6.6) versus 0.72% (0.48–0.9), RR?=?3.7, preterm delivery in 25.2% (13.0–41.7) versus 6.0% (4.7–7.1), RR?=?4.2 and delivery of large for gestational infants in 54.2% (45.1–62.5) versus 10.0%, RR?=?4.5. Early pregnancy HbA_1c was positively associated with adverse pregnancy outcomes.

Conclusion: The risk of adverse pregnancy outcomes was two to five times increased in women with T1DM compared with the general population. The goals of the St. Vincent declaration have not been achieved.     

Pregnancy risk factors for very premature delivery: what role do hypertension, obesity and diabetes play?

Purpose

Very premature delivery is a major cause of infant morbidity and mortality. Obesity, diabetes and pregnancy hypertension are known risk factors for pregnancy complications. The study aimed to scrutinize differences of pregnancy complications in a cohort of very premature deliveries compared to a national group.

Methods

In a multicenter study performed between January 2009 and December 2010 including 1,577 very low birth weight (VLBW) infants, we compared parental reported pregnancy problems of VLBW infants with a national cohort (KIGGS). We compared reported pregnancy complications to reasons for premature delivery and neonatal outcome within the group of VLBW infants.

Results

While parents of the national cohort reported pregnancy-induced hypertension in 8 %, parents of VLBW infants reported this complication more frequently (27 %). Mothers of the national cohort were significantly younger (1 year), suffered less from obesity, anaemia, diabetes. Regression analysis showed that hypertension (OR = 5.11) and advanced maternal age (OR = 1.03) increased the risk for premature birth. Women with hypertension were likely to experience a clinically indicated premature delivery, had more VLBW infants with a moderate growth restriction, but less multiples and their infants had less intraventricular haemorrhages grade 3 or 4. Otherwise, neonatal outcome was correlated with gestational age but not with the pregnancy complications diabetes, hypertension or obesity.

Conclusion

Premature birth seems to be correlated to gestational hypertension and associated problems in about ¼ of VLBW infants. Further studies should focus on preventing and treating gestational hypertension to avoid premature delivery and associated neonatal morbidity.     

GDM women in good glycemic control: which meal-related measure enhances fetal well-being?

OBJECTIVE: To determine which meal-related glucose measure maximizes perinatal outcome in gestational diabetes mellitus (GDM) women who have achieved established levels of glycemic control. METHODS: Two thousand two hundred and ninety-eight GDM women were stratified by meal-related blood glucose measures: fasting (<95 mg/dL); pre-meal (< or =90 mg/dL); 2-h post-meal (< or =120 mg/dL); mean (< or =100 mg/dL). The rates of unidentified adverse outcome for composite outcome, neonatal intensive care unit (NICU), metabolic and respiratory complications and cesarean section delivery within each meal-related glucose threshold were calculated. RESULTS: Overall, 25-69% of large-for-gestational-age (LGA)/macrosomic infants were not identified within the recommended meal-related glucose threshold measurements. The lowest rates of unidentified morbidity were found in the pre-meal and mean blood glucose categories while the highest rates were in the post-meal category despite subjects achieving recommended levels of glycemic control. The increased rate of LGA/macrosomia within 10 mg/dL increments for each meal-related glucose category revealed that regardless of the meal-related category, the rate of LGA was significantly higher (15-25%). Logistic regressions (dependent variable= composite outcome or LGA) showed that mean blood glucose was the only significant contributor. CONCLUSION: Currently recommended meal-related glucose measures do not preclude adverse fetal outcome.     

Fibroids and in-vitro fertilization: which comes first?

PURPOSE OF REVIEW: There is no consensus about the impact of uterine fibroids on fertility. This review explores past and recent studies that investigated the effects of submucosal, intramural, and subserosal fibroids on in-vitro fertilization (IVF) outcomes. We discuss the importance of proper evaluation of the uterus and endometrial cavity, and current options for optimal fibroid management in patients desiring fertility. RECENT FINDINGS: Several studies have reviewed the data on fibroids and infertility, further exploring this potential relationship. Two recent studies investigated reproductive outcomes before and after myomectomy, and IVF outcomes based on fibroid size and location. Both studies concluded that fibroids can impair reproductive outcomes. Several papers thoroughly reviewed medical and surgical management options for patients with fibroids and desired fertility. Although several medical therapies may reduce fibroid volume or decrease menorrhagia, myomectomy remains the standard of care for future fertility. Recent data identified an increased rate of pregnancy complications after uterine artery embolization compared with laparoscopic myomectomy. A new procedure, magnetic resonance imaging-guided focused ultrasound ablation, shows promise for the management of symptomatic fibroids, and possibly for the management of fibroids prior to pregnancy. As with embolization, more data are needed to evaluate postprocedure fertility and pregnancy outcomes. SUMMARY: Fibroid location, followed by size, is the most important factor determining the impact of fibroids on IVF outcomes. Any distortion of the endometrial cavity seriously affects IVF outcomes, and myomectomy is indicated in this situation. Myomectomy should also be considered for patients with large fibroids, and for patients with unexplained unsuccessful IVF cycles.     

Can ultrasound fetal biometry predict fetal hyperinsulinaemia at delivery in pregnancy complicated by maternal diabetes?

OBJECTIVE: The aim of this study was to determine whether there is an association between ultrasound fetal biometry and amniotic fluid insulin levels at delivery in women with pre-existing diabetes or impaired glucose tolerance in pregnancy. STUDY DESIGN: This retrospective cohort study identified 93 women who had amniotic fluid insulin levels measured at time of delivery. Standardised estimated fetal weight and fetal growth velocity were calculated from serial third trimester fetal ultrasound measurements. RESULTS: Women with pre-existing diabetes had significantly greater mean growth velocity [1.39 (95% CI: 0.43-2.23) versus 0.39 (95% CI: -01.7-0.95); p=0.04], significantly greater mean estimated fetal weight (EFW) Z score prior to delivery [2.36 (95% CI: 1.82-2.9) versus 1.38 (95% CI: 1.02-1.74); p=0.002] and greater mean birthweight centile [82 (95% CI: 0.74-0.89) versus 67 (95% CI: 58-76); p=0.02] than those with GDM/IGT. Amniotic fluid insulin levels demonstrated a similar significant difference between the pre-existing and GDM/IGT groups [20.5 (95% CI: 12.9-28.1) versus 8.5 (95% CI: 5.4-11.7); p=0.001]. An association between fetal growth and size and amniotic fluid insulin was observed in women with pre-existing diabetes. Positive likelihood ratios were 1.67 and 2.08, respectively, for the prediction of liquor insulin greater than the 95th centile in women with pre-existing diabetes. CONCLUSION: Ultrasound measures of fetal size and growth used in this study are not sufficiently accurate to predict those infants likely to be at risk from the adverse effects of fetal hyperinsulinaemia.     

Placental urocortin-2 and -3: Endocrine or Paracrine Functioning During Healthy Pregnancy?

ObjectivesPlacental urocortins may affect uterine quiescence by modulating in an endocrine or paracrine way the estradiol secretion by the adjacent placenta. The aim of this study was to investigate the role of placental urocortin-2 and -3 as endocrine or as auto/paracrine messengers in concert with placental estradiol generation.Study designIn a cross-sectional study, plasma was obtained from healthy pregnant women, between 10 and 42 gestational weeks, and from nonpregnant women. Third trimester plasma pools were used for urocortin-2 and -3 peptide characterization by HPLC and RIA. Plasma samples (gestational age 10 and 42 wk) were analyzed using validated radioimmunoassays specific for urocortins and corticotropin-releasing factor (CRF). To reveal possible local actions of urocortins the influence of urcortin-2 on the estradiol secretion from placental tissue cultures was investigated.ResultsReversed-phase HPLC fractionation of plasma extracts revealed several peaks containing immunoreactive-like urocortin-2 or -3, of which the main peaks had the same retention time as the synthetic urocortin-2 or -3 peptides. In contrast to plasma CRF, no gestational age dependent changes in plasma urocortin-1, -2 and -3 levels occurred. The mean plasma urocortin levels during gestation did not differ from postpartum levels. In vitro, urocortin-2 stimulated dose-dependently the placental estradiol secretion, a stimulation inhibited by antisauvagine-30, a CRF-receptor 2 antagonist.ConclusionPlacentas of healthy pregnant women do not, or not to any great extent, secrete urocortin-2 and -3 in the plasma. We show that urocortins can regulate the estradiol secretion from placental tissue cultures via the CRF-R2 mediated pathway. Therefore, placental urocortin-2 and -3 peptides are more likely to function as auto/paracrine messengers during healthy pregnancy, than as endocrine messengers.     

Pregnancy and Medicine: sine qua non or non sequitur?

Pregnancy is intrinsically imperfect, with high rates of complications for mothers and babies. A minority of pregnancies is entirely uncomplicated. Medical disorders are frequent contributors to morbidity for mothers and babies, and have become the major source of maternal mortality. For these reasons, Medicine plays a central role in the care of pregnant women. Provision of resources to maternity services must recognise the changing demographics and clinical characteristics of pregnant women in Australia, and their increased medical risk status in recent years.     

Massive fetomaternal hemorrhage and fetal death: are they predictable?

OBJECTIVE: To report the incidence of massive fetomaternal hemorrhage (FMH) associated with fetal death and to test the hypothesis that FMH is more likely to occur in those with risk factors for FMH. STUDY DESIGN: All cases of fetal death of infants weighing > 500 gm between January 1, 1990 and December 31, 1994 were reviewed for evidence of massive FMH (> or = 2% fetal cells in the maternal circulation as measured by the Betke-Kleihauer test). Women with risk factors were compared with those without risk factors with respect to the occurrence of massive FMH. RESULTS: The prevalence of massive FMH was 14 of 319 (4.4%) cases, occurring in 4 of 102 (3.9%) of those with risk factors and 10 of 217 (4.6%) of patients without risk factors (p = 0.78). Otherwise unexplained fetal death was associated with massive FMH in 5 of 141 (3.5%). Major fetal anomalies were present in 5 of 14 (35.7%) cases of massive FMH. CONCLUSION: Clinical risk factors do not predict an increased likelihood of massive FMH. Massive FMH is associated with fetal anomalies. Betke-Kleihauer testing should be performed in all cases of fetal death, including those with anomalies regardless of the presence or absence of risk factors for FMH.     

Obesity or diabetes: which is more hazardous to the health of the offspring?

Objective: To examine impact on perinatal outcome of untreated gestational diabetes (GDM) and non-diabetics stratified by body mass index (BMI).

Research design and methods: This is a secondary analysis of our investigation of the consequences of not treating GDM. We evaluated 555 untreated GDMs matched to 1100 non-diabetics. BMI was determined using subjects’ recalled pre-pregnancy weight. A primary composite variable consisted of stillbirth, neonatal macrosomia/large-for-gestational-age (LGA), neonatal hypoglycemia, erythrocytosis and hyperbilirubinemia. Secondary outcomes included shoulder dystocia, respiratory complications, cesarean delivery and pregnancy-related hypertension.

Results: Untreated subjects in the normal weight category had an ～2-fold increase for composite outcome and LGA and a 7-fold increase in metabolic complications. The overweight untreated group showed composite outcome, LGA and metabolic complications 2–3-fold higher and induction of labor 5-fold higher. For obese untreated GDMs, significantly higher rates of composite outcome, LGA and metabolic complications, induction of labor and cesarean delivery were 10-, 3-, 5-, 4- and 9-fold, respectively. Perinatal outcome for normal weight untreated GDM was similar to obese non-diabetics.

Conclusions: Maternal obesity and GDM independently affect adverse pregnancy outcome. The combination has a greater impact than each one alone. However, glycemic level contributes a greater portion to the adverse pregnancy equation.