The effect of methyldopa treatment on uterine, umblical and fetal middle cerebral artery blood flows in preeclamptic patients

The impact of anti-hypertensive treatment on foetal growth and haemodynamics in pregnant women with pre-existing diabetes - An explorative study

OBJECTIVES

To explore the impact of anti-hypertensive treatment of pregnancy-induced hypertension on foetal growth and hemodynamics in women with pre-existing diabetes.

METHODS

A prospective cohort study of 247 consecutive pregnant women with pre-existing diabetes (152 type 1 diabetes; 95 type 2 diabetes), where tight anti-hypertensive treatment was initiated and intensified (mainly with methyldopa) when office blood pressure (BP) ≥135/85 mmHg and home BP ≥130/80 mmHg. Foetal growth was assessed by ultrasound at 27, 33 and 36 weeks and foetal hemodynamics were assessed by ultrasound Doppler before and 1-2 weeks after initiation of anti-hypertensive treatment.

RESULTS

In 215 initially normotensive women, anti-hypertensive treatment for pregnancy-induced hypertensive disorders was initiated in 42 (20%), whilst 173 were left untreated. Chronic hypertension was present in 32 (13%). Anti-hypertensive treatment for pregnancy-induced hypertensive disorders was not associated with foetal growth deviation (linear mixed model, p = 0.681). At 27 weeks, mainly before initiation of anti-hypertensive treatment, the prevalence of small foetuses with an estimated foetal weight <10th percentile was 12% in women initiating anti-hypertensive treatment compared with 4% in untreated women (p = 0.054). These numbers were close to the prevalence of birth weight ≤10th percentile (small for gestational age (SGA)) (17% vs. 4%, p = 0.003). Pulsatility index in the umbilical and middle cerebral artery remained stable after the onset of anti-hypertensive treatment in a representative subgroup (n = 12, p = 0.941 and p = 0.799, respectively).

CONCLUSION

There is no clear indication that antihypertensive treatment causes harm in this particular at-high-risk group of pregnant women with diabetes, such that a larger well-designed study to determine the value of tight antihypertensive control would be worthwhile.

Economic evaluation of Community Level Interventions for Pre-eclampsia (CLIP) in South Asian and African countries: a study protocol

BACKGROUND

Globally, hypertensive disorders of pregnancy, particularly pre-eclampsia and eclampsia, are the leading cause of maternal and neonatal mortality, and impose substantial burdens on the families of pregnant women, their communities, and healthcare systems. The Community Level Interventions for Pre-eclampsia (CLIP) Trial evaluates a package of care applied at both community and primary health centres to reduce maternal and perinatal disabilities and deaths resulting from the failure to identify and manage pre-eclampsia at the community level. Economic evaluation of health interventions can play a pivotal role in priority setting and inform policy decisions for scale-up. At present, there is a paucity of published literature on the methodology of economic evaluation of large, multi-country, community-based interventions in the area of maternal and perinatal health. This study protocol describes the application of methodology for economic evaluation of the CLIP in South Asia and Africa.

METHODS

A mixed-design approach i.e. cost-effectiveness analysis (CEA) and qualitative thematic analysis will be used alongside the trial to prospectively evaluate the economic impact of CLIP from a societal perspective. Data on health resource utilization, costs, and pregnancy outcomes will be collected through structured questionnaires embedded into the pregnancy surveillance, cross-sectional survey and budgetary reviews. Qualitative data will be collected through focus groups (FGs) with pregnant women, household male-decision makers, care providers, and district level health decision makers. The incremental cost-effectiveness ratio will be calculated for healthcare system and societal perspectives, taking into account the country-specific model inputs (costs and outcome) from the CLIP Trial. Emerging themes from FGs will inform the design of the model, and help to interpret findings of the CEA.

DISCUSSION

The World Health Organization (WHO) strongly recommends cost-effective interventions as a key aspect of achieving Millennium Development Goal (MDG)-5 (i.e. 75 % reduction in maternal mortality from 1990 levels by 2015). To date, most cost-effectiveness studies in this field have focused specifically on the diagnostic and clinical management of pre-eclampsia, yet rarely on community-based interventions in low-and-middle-income countries (LMICs). This study protocol will be of interest to public health scientists and health economists undertaking community-based trials in the area of maternal and perinatal health, particularly in LMICs.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01911494.

Predictive value of middle cerebral artery to uterine artery pulsatility index ratio in hypertensive disorders of pregnancy

Aims and Objectives. (i) To determine the predictive value of cerebrouterine (CU) ratio (middle cerebral artery to uterine artery pulsatility index, MCA/UT PI) in assessing perinatal outcome among hypertensive disorders of pregnancy. (ii) To compare between CU ratio and CP ratio (MCA/Umbilical artery PI) as a predictor of adverse perinatal outcome. Methods. A prospective observational study was done in a tertiary medical college hospital, from September 2012 to August 2013. One hundred singleton pregnancies complicated by hypertension peculiar to pregnancy were enrolled. Both CU and CP ratios were estimated. The perinatal outcomes were studied. Results. Both cerebrouterine and cerebroplacental ratios had a better negative predictive value in predicting adverse perinatal outcome. However, both CU and CP ratios when applied together were able to predict adverse outcomes better than individual ratios. The sensitivity, specificity, positive predictive value, and the negative predictive values for an adverse neonatal outcome with CU ratio were 61.3%, 70.3%, 56%, and 78.9%, respectively, compared to 42%, 57.5%, 62%, and 76% as with CP ratio. Conclusion. Cerebrouterine ratio and cerebroplacental ratio were complementary to each other in predicting the adverse perinatal outcomes. Individually, both ratios were reassuring for favorable perinatal outcome with high negative predictive value.

Assessment of fetal cardiac function in mild preeclampsia

This study investigated cardiac function in 65 fetuses of mildly preeclamptic mothers and 55 fetuses of healthy mothers at 26-40 weeks of gestation. Fetuses with intrauterine growth restriction were excluded. Cardiac functions were evaluated by M-mode, pulsed-wave, and tissue Doppler echocardiography. The two groups were similar in terms of maternal age, gravidity, parity, and gestational age. Peak systolic aortic and pulmonary artery velocities were significantly lower in the fetuses of the preeclamptic mothers than in the fetuses of the healthy mothers. The two groups did not differ significantly in terms of shortening fraction or with regard to mitral or tricuspid annular plane systolic excursion. Pulsed-wave Doppler-derived E/A ratios in the mitral and tricuspid valves were similar in the two groups. The deceleration time of early mitral inflow was prolonged in the fetuses of the preeclamptic mothers. The Ea, Aa, and Ea/Aa ratios in the interventricular septum, left ventricle posterior wall, and right ventricle free wall were lower in the preeclampsia group than in the control group. The E/Ea ratio was higher in the preeclampsia group than in the control group. The isovolumic relaxation time and the right and left myocardial performance indices were higher in the fetuses of the preeclamptic mothers than in the fetuses of the healthy mothers. An increased ductus venosus pulsatility index (PI) and a decreased middle cerebral artery (MCA) PI were found in the fetuses of the preeclamptic mothers. All the fetuses were asymptomatic. The results suggest that the increase in fetal cardiac afterload in mild preeclampsia may have caused early subclinical changes in fetal systolic and diastolic cardiac function. In addition, the decrease in MCA-PI may have been caused by redistribution of fetal cardiac output in favor of the left ventricle, secondary to increased placental vascular resistance.

Beyond the placental bed: placental and systemic determinants of the uterine artery Doppler waveform

The uterine artery Doppler waveform has been extensively investigated, though its widespread clinical use as a predictor of adverse pregnancy outcome remains under debate. The determinants of the waveform have classically been ascribed to transformation of the spiral arteries and the development of a low resistance uteroplacental circulation, failure of which predisposes to pre-eclampsia, fetal growth restriction and other adverse outcomes. It has become increasingly evident that although spiral artery transformation determines in some part the characteristics of the Doppler waveform, factors pertaining to maternal vascular and endothelial function are also important.

Predictive value of middle cerebral artery to uterine artery pulsatility index ratio in preeclampsia

OBJECTIVE

To determine the predictive value of middle cerebral artery (MCA) to uterine artery pulsatility index (PI) ratio in preeclamptic patients.

METHODS

This prospective cross-sectional study was performed on 64 preeclamptic and 131 normal pregnancies at or beyond 26 weeks of gestation between June 2007-August 2008 in the high-risk pregnancy unit of Dr. Zekai Tahir Burak Women Health Teaching and Research Hospital, Ankara. Doppler blood flow velocimetry of the uterine and umbilical arteries and fetal MCA was measured. The ratios between the PI of MCA and the mean PI value of both uterine arteries were calculated and values below the fifth percentile were considered as brain-sparing. The ratios between the PI of MCA and PI of the umbilical artery were calculated and values lower than 1.08 were considered as brain-sparing and the results were related to perinatal outcome. Statistical analysis were performed using the SPSS Software (SPSS, Chicago, IL, USA) version 9.0 for Windows. Odds ratio with 95% confidence interval (95%) was also used for statistical analysis.

RESULTS

In 11 (42.3%) of the preeclamptic pregnancies that had abnormal MCA/uterine artery PI, 4 of them had severe preeclampsia and 7 had mild preeclampsia. In the low MCA/uterine artery PI ratio group, a statistically significantly higher rate of Cesarean section (66 vs. 88.46%), NICU admission (26.3 vs. 57.6%), preterm birth (52.6 vs. 92.3%) was found. Abnormal MCA/uterine artery PI ratio and abnormal MCA/umbilical artery PI ratio in the prediction of adverse outcome of pregnancy was compared. In the prediction of preterm birth, which was better for the MCA/uterine artery, there was a significant difference between the ratios (P = 0.005).

CONCLUSION

Our results suggest that MCA/uterine artery PI ratio is a good predictor of neonatal outcome in preeclamptic patients in the third trimester and could be used to identify fetuses at risk of morbidity and mortality.

[Fetal cerebral-umbilical Doppler ratio in prediction of fetal distress in patients with preeclampsia]

BACKGROUND/AIM

The use of color Doppler ultrasonography provides noninvasive observation, confirmation and quantification of pathophysiological processes in fetoplacental circulation in pregnant patients. By blood vessel mapping and the obtained waves spectral analysis it is posible to evaluate vascular resistency of the fetus blood vessels. The aim of the study was to evaluate cerebral-umbilical pulsatility index ratio in fetal circulation in prediction of fetal distress in patients with preeclampsia.

METHODS

By measurement of pulsatility indices in medial cerebral and umbilical arteries in 400 patients with uncomplicated pregnancy, normal values were calculated for fetuses from 15-40 weeks. In our study group 70 patients with preeclampsia were included. Cerebral-umbilical (C/U) ratio was calculated after pulsatility indices in medial cerebral artery and umbilical artery determining by the spectral Doppler analysis of flow velocity waveforms in these vessels. Fetal outcome was analyzed by measurement of the Apgar score at the 5th minute and fetal pH at birth.

RESULTS

The mean C/U ratio values in the third trimester of normal pregnancy were between 1.8 and 1.9. The mean C/U ratio values in the patients complicated with preeclampsia were significantly lower comparing to normal pregnancies (ANOVA, p < 0.05). The mean 5th minute Apgar score in the study group was 6.35 +/- 1.58, and the mean fetal pH at birth was 7.16 +/- 0.15. Linear regression test showed a highly significant correlation between low C/U ratio and fetal pH at birth in patients with preeclampsia (r = 0.49, p < 0.01).

CONCLUSION

The C/U ratio values obtained from spectral Doppler analysis in fetal vessels showed a highly significant correlation with fetal pH at birth in the patients with preeclampsia. The results of our study confirmed the reliability of C/U ratio in estimation of fetal condition in preeclamptic patients. Very low C/U ratio values in patients with preeclampsia indicate that in these fetuses fetal acidosis and fetal distress may be expected.

Effect of antihypertensive therapy with alpha-methyldopa on uterine artery Doppler in pregnancies with hypertensive disorders

OBJECTIVES

Antihypertensive drugs lower blood pressure by direct vascular effects or central vasodilatory mechanisms. Their effect on uterine artery Doppler resistance indices in hypertensive disorders of pregnancy is uncertain. This study aimed to evaluate the impact of antihypertensive therapy with alpha-methyldopa on maternal uterine artery Doppler pulsatility index (PI) and resistance index (RI) in women presenting with hypertensive disorders of pregnancy.

METHODS

This was a cross-sectional study of 51 women with pre-eclampsia, 29 with gestational hypertension and 80 matched normotensive controls. Uterine artery PI and RI were measured at recruitment (between 24 and 40 weeks' gestation) and, in the hypertensive groups, 24-48 h after starting alpha-methyldopa. Differences between mild and severe, and between early- and late-onset pre-eclampsia were compared using the Mann-Whitney test. The Wilcoxon rank sum test was used to compare measurements before and after treatment.

RESULTS

Prior to treatment, uterine artery PI and RI were significantly higher in women with pre-eclampsia compared with those with gestational hypertension and controls (P < 0.0001). The median uterine artery PI multiple of the median (MoM) was significantly higher (P < 0.0001) in early-onset than in late-onset pre-eclampsia (1.83 (range, 0.88-3.65) vs. 1.19 (range, 0.91-1.72)) and in severe compared with mild disease (2.26 (range, 2.02-3.65) vs. 1.29 (range, 0.88-2.9)). Uterine artery PI- and RI-MoMs in both pre-eclampsia and gestational hypertension, before and after 34 weeks' gestation, were not affected by alpha-methyldopa treatment.

CONCLUSIONS

Antihypertensive therapy using alpha-methyldopa in women presenting with hypertensive disorders of pregnancy has no significant effect on uterine artery resistance to blood flow, suggesting that it does not impair uteroplacental circulation in these cases.

Medications in pregnancy and lactation: Part 2. Drugs with minimal or unknown human teratogenic effect

This is the second of a two-part series on the use of medication during pregnancy and lactation. Pregnancy risk factors together with an increased incidence of chronic diseases and the rise in mean maternal age predict an increase in medication use during gestation. However, as highlighted in the first installment of this series, relatively few medications have specifically been tested for safety and efficacy during pregnancy, and, therefore, responses to those inquiries can be uninformed and inaccurate. Whereas the first installment provided new insight into the nature of medications with known human teratogenic effects, this part concentrates on drugs with minimal or no known human teratogenic effect. It is important that clinicians become familiar with all of the aspects of the drugs they prescribe, in addition to the controversies surrounding them, through consultation with maternal-fetal medicine specialists and through references and Web sites providing up-to-date information in an effort to promote safer prescribing practices.

Pathophysiology and Medical Management of Systemic Hypertension in Pregnancy

Hypertension in pregnancy includes a group of distinct disorders that require special consideration in both prevention and pharmacologic treatment. In recent years, there have been few advances regarding the pathophysiology and prevention of preeclampsia or in the recommendations for first-line drug therapy for its hypertensive complications. Similarly, the recommendations for pharmacologic treatment of women with chronic hypertension antedating pregnancy have changed little primarily because first-line medications have the advantage of having had more extensive research experience. Recent clinical trials have demonstrated the efficacy and safety of various second-line drugs for the hypertensive disorders of pregnancy; whether these therapies can eventually replace the standard recommended medications will require more extensive long-term investigation.