Uterine artery impedance during the first eight postpartum weeks

Postpartum Uterine Artery Doppler Indices when Leaving the Placenta In Situ for Placenta Accreta Spectrum

This study aimed to evaluate longitudinal changes in uterine artery (UtA) Doppler velocimetry in patients with placenta accreta spectrum (PAS) managed by leaving the placenta in situ (LPIS) postpartum.This is a prospective cohort study of patients with PAS managed by LPIS for either planned interval hysterectomy or uterine preservation who underwent serial postpartum ultrasounds. We included patients who had Doppler velocimetry of the UtA obtained before delivery and postpartum. Left, right, and mean (m) peak systolic velocity (PSV), end-diastolic velocity (EDV), and pulsatility index (PI) were recorded. Our goal is to describe changes in these Doppler indices over time and to make comparisons with normal postpartum reference values.A total of 34 patients were included: 19 planned for uterine-sparing management and 15 planned for interval hysterectomy. No significant differences in mUtA PI, mPSV, and mEDV were documented between predelivery values and those obtained within the first eight weeks postpartum, however after 8 weeks there was a significant increase in mUtA PI (0.80-1.49; p < 0.001), while mUtA PSV (103.8-58.6 cm/s; p = 0.002) and mEDV (53.5-15.8 cm/s; p < 0.001) decreased significantly. Patients opting for uterine-sparing management who successfully retained their uterus showed a trend for higher mUtA PI, PSV, and EDV than those who underwent an interval hysterectomy. mUtA PI postpartum values were lower in our study group compared to those reported from postpartum patients without PAS.In comparison to patients without PAS, mUtA PI is markedly lower in LPIS patients in the first 8 weeks. In patients undergoing LPIS for PAS, UtA Doppler indices start to show significant changes at ≥ 8 weeks postpartum compared to predelivery values, with a significant increase in mUtA PI and a reduction in mUtA PSV and EDV. Future studies are needed to evaluate the clinical utility of these findings. · UtA PI is lower when the placenta is left in situ.. · UtA PI increases and velocities decrease after 8 weeks.. · Those who retain their uterus have higher UtA PI..

Pathophysiology of Maternal Obesity and Hypertension in Pregnancy

Obesity is one of the biggest health problems in the 21st century and the leading health disorder amongst women of fertile age. Maternal obesity is associated with several adverse maternal and fetal outcomes. In this group of women, the risk for the development of hypertensive disorders of pregnancy (HDPs), such as gestational hypertension (GH) and pre-eclampsia (PE), is increased. In fact, there is a linear association between an increase in pre-pregnancy body mass index (BMI) and PE. Excessive weight gain during pregnancy is also related to the development of PE and GH. The role of obesity in the pathophysiology of HDP is complex and is most likely due to an interaction between several factors that cause a state of poor maternal cardiometabolic health. Adipokines seem to have a central role in HDP development, especially for PE. Hypoadiponectinemia, hyperleptinemia, insulin resistance (IR), and a proinflammatory state are metabolic disturbances related to PE pathogenesis, contributing to its development by inducing a state of maternal endothelial dysfunction. Hypertriglyceridemia is suggested to also be a part of the disease mechanisms of HDP. Therefore, this review seeks to explore the scientific literature to assess the complications of maternal obesity and its association with the development of HDP.

Assessment of Uterine Blood Flow in Mild Primary Dysmenorrhea

Purpose

We aimed to assess uterine and arcuate artery Doppler indices in patients with mild primary dysmenorrhea.

Patients and Methods

A total of 55 patients were included, consisting of women without dysmenorrhea (n=26, group A) and women with mild primary dysmenorrhea (n=29, group B). Doppler measurements of the uterine and arcuate arteries were performed in both groups on the 1st-2nd days and 21st-24th days (midluteal phase) of the menstrual cycle using transvaginal ultrasound and compared between the groups. The severity of dysmenorrhea was assessed using visual analog scale scores.

Results

Doppler measurements of the uterine and arcuate arteries performed on the 1st-2nd days of the menstrual cycle and the midluteal phase were similar between the groups (p>0.05). There was a significant decrease in the intragroup measurements of uterine and arcuate arteries performed on the first day of menstruation and the luteal phase in both groups (p<0.01).

Conclusion

Doppler findings of the uterine and arcuate arteries did not differ between patients with and without mild primary dysmenorrhea. The etiology of primary dysmenorrhea mainly involves ischemia and vasoconstriction, but mild primary dysmenorrhea appears to be associated with a different etiology other than decreased tissue perfusion.

Antepartum and postpartum uterine artery impedance in women with pre-eclampsia: a case control study

This is a cohort study which included 100 cases with pre-eclampsia (PE) and 100 controls, done to compare the antepartum and postpartum uterine artery (UtA) Doppler velocimetry between them. UtA PI and RI were measured before and within 48-72 h after delivery. There was a highly significant difference between the cases and controls, regarding the UtA RI (0.70 ± 0.10 and 0.72 ± 0.10, versus 0.59 ± 0.12 and 0.60 ± 0.11) and PI (1.41 ± 0.89 and 1.45 ± 0.90 versus 0.85 ± 0.30 and 0.90 ± 0.34) measured at the antepartum and postpartum periods, respectively. Age and gestational age were significantly related to the postpartum and changes in the UtA PI. The gestational age was also correlated to UtA RI changes. Both the antepartum and postpartum mean blood pressure were correlated with postpartum UtA RI and PI and PI changes after delivery. We concluded that uterine artery Doppler indices changes are more common in women with PE, than in normotensive women with significant correlations with age and gestational age. Impact statement What is already known on this subject? After delivery, the haemodynamic changes that occurred with pregnancy reverse. Both the heart rate and the cardiac output decreased to reach the non-pregnant state. Impedance to flow in the uterine artery rises as the nutritional needs are decreased abruptly. What do the results of this study add? Both the antepartum and postpartum measurement of uterine artery Doppler indices is significantly higher in women with PE when compared to control women. The persistent uterine artery impedance is a result of inadequate trophoblastic invasion within the basal part of the decidua basalis and myometrium or persistently increased maternal vascular tone. What are the implications of these findings for clinical practice and/or further research? The uterine artery Doppler parameters return to the non-pregnant values in normal pregnancies. Knowing such information may help in understanding the haemodynamics of the uterine vasculature during puerperium in hypertensive patients.

Uterine artery flow velocity waveforms before and after delivery in hypertensive disorders of pregnancy near term

OBJECTIVE

To compare the uterine artery pulsatility index (UtAPI-AP) before labor and immediate postpartum (UtAPI-PP) in hypertensive disorders of pregnancy (HTNP) and normotensives near term.

METHODS

Pregnancies ≥36 weeks admitted for labor induction in our institution from October 2015 to October 2017 were included. We excluded active labor, multiple gestations, fetal demise, and those with inadequate uterine artery sampling. Our primary outcome was to compare the UtAPI-AP and UtAPI-PP between subjects with HTNP (gestational hypertension, preeclampsia with and without severe features) and normotensive participants. Our secondary outcomes were to compare the UtAPI-AP and UtAPI-PP by subgroups (severe HNTP, non-severe HTNP, and controls) and the UtAPI-PP in participants while on MgSO₄ and after its discontinuation. A linear regression model was applied to test the above associations. A P < .05 was considered significant.

RESULTS

We included 108 women (HTNP = 71; controls = 37). The UtAPI-AP was higher in the HTNP group (.85 ± .3 vs. .71 ± .2; P < .001); however, the UtAPI-PP was not different between groups (1.11 ± .3 vs. 1.16 ± .4; P = .46). The UtAPI-AP was higher in the severe HTNP group than controls (P = .004), but there was no significant difference in the UtAPI-PP between subgroups. Our results remained unchanged after adjusting for confounders. The UtAPI while on MgSO₄ and after its discontinuation was similar (P =  >.99).

CONCLUSION

The increased UtAPI in patients with HTNP resolves soon after delivery. MgSO₄ does not seem to have an effect on the UtAPI postpartum.

Physiological Uterine Involution in Primiparous and Multiparous Women: Ultrasound Study

PURPOSE

To examine the uterine involution period after uncomplicated delivery in primiparous and multiparous women.

METHODS

Longitudinal prospective study. Repeated parameters were measured and endometrial contents and diastolic notch were observed. Measurements of primiparous and multiparous women were carried out after labour on the 1st, 3rd, 10th, 30th, 42nd, and 60th postpartum days. The analysis was performed using SPSS version 21.

RESULTS

The median uterus parameters are bigger in multiparous group in physiological puerperium, but the decreasing trend is the same. The endometrial cavity on the 10th day was significantly wider in multiparous women and mainly echo-negative view of the uterine cavity was observed. The evaluation of the uterine angle deviation changes from an extremely retroverted position to a more anteverted position. RI of the uterine artery in both groups was low immediately after labour and significantly increased one month postpartum. Notching of the uterine artery undergoes changes, but diastolic notch does not appear in all postpartum women even after two months following labour.

CONCLUSIONS

The puerperium period after normal vaginal delivery depends on parity. The trend of involution in primiparous and multiparous women follows a similar pattern, yet, it lasts longer in the multiparous women. Ultrasound of uterine is certainly a useful tool after labour and may be important in facilitating an early detection of postpartum uterine complications.

Uterine artery pulsatility index in hypertensive pregnancies: When does the index normalize in the puerperium?

Objective

To investigate whether the uterine artery pulsatility index (UtA PI) of hypertensive pregnancies is higher than that of normal pregnancies in the puerperium, as well as in the antepartum period.

Methods

The UtA PI was measured in hypertensive (group 1) and normal pregnancies (group 2) during antepartum, immediate postpartum or late postpartum periods. Using the transvaginal approach, the bilateral uterine artery indices were measured.

Results

One hundred twenty-two women were enrolled: group 1, hypertensive disease in pregnancy (11 cases in antepartum, 13 cases in immediate postpartum and 10 cases in late postpartum period); group 2, normal pregnancies (32 cases in antepartum, 29 cases in immediate postpartum and 27 cases in late postpartum). In antepartum and immediate postpartum periods, the mean UtA PI and the proportion of cases with an early diastolic notch were higher in group 1 than in group 2 (antepartum mean UtA PI, 1.14 in group 1 vs. 0.68 in group 2, P<0.001; early diastolic notch, 46% vs. 9%, P<0.05; immediate postpartum mean UtA PI, 1.30 vs. 1.08, P<0.05; early diastolic notch, 85% vs. 48%, P<0.05). In late postpartum period, the mean value of UtA PI of group 1 was still higher than that of group 2, although the proportion of cases with an early diastolic notch was not different (mean UtA PI, 1.43 vs. 1.20, P<0.05; early diastolic notch, 60% vs. 52%, P=0.73).

Conclusion

The UtA PI in hypertensive pregnancies was still higher than normal pregnancies in puerperal periods, suggesting that more than several weeks are required to resolve increased uterine artery vascular impedance.

Postpartum uterine artery blood flow impedance following cesarean section or vaginal delivery

PURPOSE

To compare uterine arteries (UtA) blood flow after cesarean section (CS) or vaginal delivery (VD).

METHODS

We performed a prospective case-control study comparing UtA blood flow impedance in patients who delivered by CS or VD. The UtA pulsatility index (PI) was measured with Doppler ultrasound during post partum using a transabdominal convex probe. Maternal and gestational age, parity, gravidity, and delay between delivery and Doppler measurement were noted.

RESULTS

We examined 106 postnatal patients, of whom 35 had CS delivery and 71 had VD. The median delay from delivery to Doppler measurement was 35 hours for the CS group and 32 hours for the VD group. The mean PI following CS and VD was 1.62 ± 0.45 and 1.42 ± 0.47, respectively. Using a linear model, the regression coefficients for mean, right, and left PI were not significantly different depending on the mode of delivery. There was no difference between emergency and elective CS.

CONCLUSIONS

Early postpartum UtA blood flow impedance is not significantly different after CS or VD. © 2015 Wiley Periodicals, Inc. J Clin Ultrasound 44:278-283, 2016.