Perinatal morbidity among women with a previous caesarean delivery (PRISMA trial): a cluster-randomised trial.

BACKGROUND: Women with a previous caesarean delivery face a difficult choice in their next pregnancy: planning another caesarean or attempting vaginal delivery, both of which are associated with potential maternal and perinatal complications. This trial aimed to assess whether a multifaceted intervention, which promoted person-centred decision making and best practices, would reduce the risk of major perinatal morbidity among women with one previous caesarean delivery. METHODS: We conducted an open, multicentre, cluster-randomised, controlled trial of a multifaceted 2-year intervention in 40 hospitals in Quebec among women with one previous caesarean delivery, in which hospitals were the units of randomisation and women the units of analysis. Randomisation was stratified according to level of care, using blocked randomisation. Hospitals were randomly assigned (1:1) to the intervention group (implementation of best practices and provision of tools that aimed to support decision making about mode of delivery, including an estimation of the probability of vaginal delivery and an ultrasound estimation of the risk of uterine rupture), or the control group (no intervention). The primary outcome was a composite risk of major perinatal morbidity. This trial was registered with ISRCTN, ISRCTN15346559. FINDINGS: 21 281 eligible women delivered during the study period, from April 1, 2016 to Dec 13, 2019 (10 514 in the intervention group and 10 767 in the control group). None were lost to follow-up. There was a significant reduction in the rate of major perinatal morbidity from the baseline period to the intervention period in the intervention group as compared with the control group (adjusted odds ratio [OR] for incremental change over time, 0·72 [95% CI 0·52-0·99]; p=0·042; adjusted risk difference -1·2% [95% CI -2·0 to -0·1]). Major maternal morbidity was significantly reduced in the intervention group as compared with the control group (adjusted OR 0·54 [95% CI 0·33-0·89]; p=0·016). Minor perinatal and maternal morbidity, caesarean delivery, and uterine rupture rates did not differ significantly between groups. INTERPRETATION: A multifaceted intervention supporting women in their choice of mode of delivery and promoting best practices resulted in a significant reduction in rates of major perinatal and maternal morbidity, without an increase in the rate of caesarean or uterine rupture. FUNDING: Canadian Institutes of Health Research (CIHR, MOP-142448).

First-trimester screening for Down syndrome using quadruple maternal biochemical markers.

OBJECTIVES: Placental growth factor (PlGF) is used for first-trimester preeclampsia screening and could be combined with other biochemical markers for Down syndrome screening. We aim to estimate the predictive value of the combination of pregnancy-associated plasma protein (PAPP-A), free ß-human chorionic gonadotropin (free ß-hCG), placental growth factor (PlGF) and α-fetoprotein (AFP) with and without nuchal translucency. METHODS: Singleton pregnancies recruited at 11-14 weeks and followed until delivery. The four maternal markers were measured using Kryptor (ThermoFisher-BRAHMS) and adjusted for gestational age and maternal characteristics. The risk of Down syndrome was calculated using the Fetal Medicine Foundation algorithm and multivariate linear regression analyses in all cases and in 2,200 controls. Receiver-operator characteristic (ROC) curves were used to calculate the detection and false-positive rates. RESULTS: Twenty-six (0.2%) cases of Down syndrome were diagnosed among 13,386 participants. The combination of the four biomarkers could have detected 88% (95% CI: 72-97%) of the cases at a false-positive rate of 13% (95% CI: 12-15%). The addition of nuchal translucency would have increased the detection rate to 96% (95% CI: 82-99%) at a false-positive rate of 4% (95% CI: 4-5%) using a 1:300 cut-off and to 100% (95% CI: 89-100%) at a false-positive rate of 6% (95% CI: 5-8%) using a 1:500 cut-off. CONCLUSIONS: First-trimester screening using biochemical markers allows the identification of approximately 88% of Down syndrome cases for a false-positive rate of 13%. The addition of nuchal translucency raises the detection rate above 95% with a false-positive rate below 5%.

Measurement of Lower Uterine Segment Thickness to Detect Uterine Scar Defect: Comparison of Transabdominal and Transvaginal Ultrasound.

OBJECTIVES: Lower uterine segment (LUS) thickness measurement using transabdominal ultrasound (TA-US), transvaginal ultrasound (TV-US), or the combination of both methods can detect scar defect in women with prior cesarean. We aimed to compare the sensitivity of three approaches. METHODS: Women with prior cesarean underwent LUS thickness measurement at 34-38 weeks' gestation. Among those who underwent repeat cesarean before labor, we compared the accuracy of TA-US, TV-US, and the thinner of the two measurements (the "combined measurement") for uterine scar dehiscence using the area under the curve (AUC) of receiver operating curves with their 95% confidence intervals (CI). We calculated the sensitivity and specificity of the three approaches using a cut-off of 2.3 mm based on prior literature. RESULTS: We included 747 participants. The mean LUS thickness was greater with TA-US (3.8 ± 1.6 mm) compared with TV-US (3.5 ± 1.9 mm) or the combined measurement (3.2 ± 1.5 mm; P < .001). The AUC was 78% (95% CI: 69%-87%), 85% (95% CI: 79%-91%), and 88% (95% CI: 82%-93%), respectively (all with P < .001). The AUC difference between TA-US and the combined measurement was not significant (P = .057). A LUS below 2.3 mm would have predicted 9 (45%) of the 20 cases of uterine scar dehiscence using TA-US, 17 (85%) using TV-US, and 18 (90%) using the combined measurement (P < .01). CONCLUSION: The choice of ultrasound approach influences the measurement of the LUS thickness. The combination of the TA-US and TV-US seems to be superior for the detection of uterine dehiscence.

First-trimester diet quality in association with maternal subcutaneous and visceral adipose tissue thicknesses and glucose homeostasis during pregnancy.

We aimed to characterise the associations between first-trimester diet quality, adiposity, and glucose homeostasis measurements throughout pregnancy in a sample of 104 healthy pregnant women. Three Web-based 24-h recalls were completed, from which the Alternate Healthy Eating Index (AHEI) was calculated. At each trimester (12.5 ± 0.7, 22.8 ± 1.0, and 33.6 ± 1.3 weeks of gestation), fasting glucose and insulin were measured to compute an insulin resistance index (HOMA-IR). Subcutaneous and visceral adipose tissue thicknesses were estimated by ultrasound at the end of the first trimester. Inverse associations were observed between the first-trimester AHEI and first-trimester fasting insulin (r = 0.24; p < 0.05), and HOMA-IR (r = -0.22; p < 0.05), as well as third-trimester fasting insulin (r = -0.20; p < 0.05). A trend was also observed between first-trimester AHEI and first-trimester SAT thickness (r = -0.17; p < 0.1). Pre- and early-pregnancy adiposity measurements were identified as high predictors fasting insulin concentrations throughout pregnancy. Higher early-pregnancy diet quality is associated with more favourable metabolic measurements during pregnancy.

Midtrimester Cervical Length in Low-Risk Nulliparous Women for the Prediction of Spontaneous Preterm Birth: Should We Consider a New Definition of Short Cervix?

OBJECTIVE: The study aimed to estimate the predictive value of midtrimester cervical length (CL) and the optimal cut-off of CL that should be applied with asymptomatic nulliparous women for the prediction of spontaneous preterm birth (sPTB). STUDY DESIGN: This is a prospective cohort study of asymptomatic nulliparous women with a singleton gestation. Participants underwent CL measurement by transvaginal ultrasound between 20 and 24 weeks of gestation. The participants and their health care providers remained blinded to the results of CL measurement. The primary outcomes were sPTB before 35 weeks and sPTB before 37 weeks. Receiver operating characteristics (ROC) curve analyses were performed. Analyses were repeated by using multiples of median (MoM) of CL adjusted for gestational age. RESULTS: Of 796 participants, the mean midtrimester CL was 40 ± 6 mm with a 1st, 5th, and 10th percentile of 25, 29, and 32 mm, respectively. ROC curve analyses suggest that a cut-off of 30 mm was the optimal CL to predict sPTB before 35 weeks (area under the ROC curve [AUC]: 0.70, 95% confidence interval [CI]: 0.56-0.85) and before 37 weeks (AUC: 0.70, 95% CI: 0.59-0.80). Midtrimester CL <30 mm could detect 35% of all sPTB before 35 weeks at a false-positive rate of 5% (relative risk: 9.1, 95% CI: 3.5-23.5, p < 0.001). We observed similar results using a cut-off of CL <0.75 MoM adjusted for gestational age. CONCLUSION: A midtrimester CL cut-off of 30 mm (instead of 25 mm), or CL less than 0.75 MoM, should be used to identify nulliparous women at high risk of sPTB. KEY POINTS: · The optimal CL cut-off for the prediction of sPTB is 30 mm in nulliparous women.. · In nulliparous women, a midtrimester CL < 30 mm is highly associated with sPTB before 35 and 37 weeks.. · A midtrimester of CL <30 mm (5th percentile) should define a short cervix in asymptomatic nulliparous women..

Ultrasonographic Transabdominal Measurement of Uterine Cervical Length for the Prediction of a Midtrimester Short Cervix.

OBJECTIVE: This study was aimed to estimate the value of transabdominal (TA) ultrasound measurement of cervical length (CL), as an alternative of transvaginal (TV) ultrasound, for universal screening of short cervix in the midtrimester. STUDY DESIGN: We conducted a prospective cohort study of nulliparous women with singleton pregnancy at 20 to 24 weeks of gestation. All participants underwent TA ultrasound followed by TV ultrasound with acquisitions of images and videos of the uterine cervix. A second sonographer, blinded to the participants' data and pregnancy outcomes, measured the CL using TA and TV images and videos. Pearson's correlation test and receiver operating characteristic (ROC) curve analyses were performed. RESULTS: A total of 805 participants were recruited, including 780 (97%) where TA CL measurement was feasible. We observed a strong correlation of CL between TA and TV (correlation coefficient: 0.57; p < 0.0001) with a mean TA measurement being 4 mm (95% confidence interval [CI]: -6 to 14 mm) below the mean TV measurement (mean of differences: 5 ± 4 mm). We observed that a TA CL <30 mm was highly predictive of a short cervix defined as a TV CL ≤25 mm (area under the ROC curve: 0.97; 95% CI: 0.95-0.99; p < 0.0001) with a sensitivity of 100% and a false-positive rate of 22%. CONCLUSION: Universal short cervix screening in nulliparous women could be performed using TA ultrasound, which could allow the avoidance of TV ultrasound in more than three quarter of women. In low-risk population, TV ultrasound could be reserved to women with TA CL <30 mm. KEY POINTS: · Cervical length (CL) measurement with transabdominal (TA) ultrasound is feasible in most cases and is strongly correlated with CL measured with transvaginal (TV) ultrasound.. · Using a cut-off of 30 mm for TA ultrasound as a first-step screening of short cervix in nulliparous women, three-quarter of TV ultrasound could have been avoided.. · Use of TA CL screening could alleviate some of the logistical challenges of universal TV CL screening..

A Pilot Randomized Trial Comparing the Effects of 80 versus 160 mg of Aspirin on Midtrimester Uterine Artery Pulsatility Index in Women with a History of Preeclampsia.

OBJECTIVE: To compare the effects of 80 mg and 160 mg of aspirin, initiated in the first trimester of pregnancy, on mid-trimester uterine artery pulsatility index (UtA-PI) in women with a history of preeclampsia. METHODS: We performed a pilot double-blind randomized controlled trial. Pregnant women with a history of preeclampsia were recruited between 100/7 and 136/7 weeks gestation and randomly assigned to take either 80 or 160 mg of aspirin daily at bedtime from randomization to 356/7 weeks gestation. The primary outcome was mean UtA-PI at 22-24 weeks. Secondary outcomes included the rate of fetal growth restriction and preeclampsia, stratified as term (≥37 weeks), preterm (<37 weeks), and early-onset (<34 weeks) preeclampsia. RESULTS: A total of 107 participants were randomized, including 41 (38%) with a history of preterm preeclampsia and 16 (15%) with a history of early-onset preeclampsia. We observed no significant difference in mean UtA-PI at 22-24 weeks between the 2 groups (0.97; 95% CI 0.88-1.05 vs. 0.97; 95% CI 0.88-1.07, P = 0.9). The rates of fetal growth restriction (8% vs. 2%; P = 0.20); preeclampsia (12% vs. 15%; P = 0.78), preterm preeclampsia (4% vs. 2%; P = 0.56), and early-onset preeclampsia (0% vs. 2%; P = 0.52) were similar in both groups. No serious adverse events associated with the study treatment were reported. CONCLUSION: We observed no significant difference in UtA-PI between the two doses of aspirin, but we observed low rates of fetal growth restriction and preterm and early-onset preeclampsia (all less than 5%). The benefits of aspirin for the prevention of preterm preeclampsia is probably not related to the improvement of deep placentation alone.

First and Third Trimester Uterine Scar Thickness in Women With Previous Caesarean: A Prospective Comparative Study.

BACKGROUND: Lower uterine segment (LUS) thickness in the third trimester of gestation is associated with the risk of uterine scar defect at delivery. It was suggested that first trimester residual myometrial thickness (RMT) could also predict uterine scar defect at delivery. OBJECTIVE: This study sought to correlate the RMT measured at the site of uterine scar in the first trimester with the LUS thickness measured in the third trimester. METHODS: This was a prospective cohort study of women with a singleton pregnancy and a single prior low-transverse CS. All participants underwent an evaluation of uterine scar by using transvaginal ultrasound at 11 to 13 weeks, including the presence of a scar defect and measurement of RMT; and a second evaluation at 35 to 38 weeks, combining both transvaginal and transabdominal ultrasound, for the measurement of LUS thickness. Spearman's correlation test was used to compare first and third trimester measurements. RESULTS: A total of 166 eligible participants were recruited at mean GA of 12.7 ± 0.5 weeks. We observed an absence of correlation between first trimester RMT and third trimester LUS thickness (correlation coefficient 0.10; P = 0.20). First trimester RMTs below 2.0 mm and below 2.85 mm are poor predictors of third trimester LUS thickness below 2.0 mm (sensitivity, 8% and 23%; specificity, 98% and 87%; positive predictive value, 25% and 14%, respectively). CONCLUSION: There is a poor correlation between first trimester RMT and third trimester LUS thickness in women with a previous CS. First trimester RMT should not be used to inform women on their risk of uterine rupture or to guide clinical management.

First-Trimester Uterine Artery Doppler for the Prediction of Preeclampsia in Nulliparous Women: The Great Obstetrical Syndrome Study.

OBJECTIVE: This study aimed to estimate the performance of first-trimester uterine artery (UtA) pulsatility index (PI) for the prediction of preeclampsia (PE). STUDY DESIGN: We conducted a prospective cohort study of nulliparous women with singleton gestation at 11 to 13 6/7 weeks. UtA-Doppler's was performed on both UtAs and the mean UtA-PI was reported in multiple of median (MoM) adjusted for gestational age. Using receiver operating characteristic curves and their area under the curves (AUC); we calculated the performance of UtA-PI for the prediction of PE. Proportional hazard models were used to develop prediction models combining UtA-PI and maternal characteristics. RESULTS: Out of 4,676 participants with completed follow-up, 232 (4.9%) developed PE, including 202 (4.3%) term and 30 (0.6%) preterm PE. Mean UtA-PI decreased with gestational age between 11 and 13 6/7 weeks (p < 0.001). First-trimester UtA-PI was associated with preterm (AUC: 0.69; 95% CI [confidence interval]: 0.57-0.80) but not with term (AUC: 0.52; 95% CI: 0.48-0.56) PE. UtA-PI combined with maternal characteristics could predict 45% of preterm PE at a false positive rate of 10%. CONCLUSION: First-trimester UtA-PI decreases with gestational age between 11 and 13 6/7 weeks and is associated with the risk of preterm but not term PE.

First-Trimester Abdominal Adipose Tissue Thickness to Predict Gestational Diabetes.

OBJECTIVE: To estimate the discriminative capacity of first-trimester subcutaneous (SATT), visceral (VATT), and total (TATT) adipose tissue thickness in predicting gestational diabetes mellitus (GDM), including that requiring insulin. METHODS: We prospectively recruited a cohort of 1048 nulliparous women. Ultrasound images were used to determine abdominal SATT, VATT, and TATT at 11 to 14 weeks' gestation. Multivariate logistic regression models were used to predict GDM, as well as insulin-requiring GDM. Model discrimination was expressed as area under the curve (AUC). RESULTS: SATT (AUC 0.66, 95% CI 0.59-0.73), VATT (AUC 0.65, 95% CI 0.58-0.73), and TATT (AUC 0.68, 95% CI 0.61-0.76) were each associated with subsequent GDM. The respective AUC values for insulin-requiring GDM were 0.70 (95% CI 0.61-0.79), 0.73 (95% CI 0.65-0.82), and 0.76 (95% CI 0.67-0.84). At a false-positive rate of 10%, the detection rate for insulin-requiring GDM was 19% for maternal age ≥35 years, 31% for a BMI ≥31.6 kg/m2, and 31% for TATT ≥61 mm, increasing to 42% in the model comprising all three measures. CONCLUSION: First-trimester ultrasound measurement of adipose tissue is associated with a higher chance of developing GDM, especially insulin-requiring GDM.

Comparative Study of Abdominal Versus Transvaginal Ultrasound for Uterine Artery Doppler Velocimetry at 11 to 13 Weeks.

OBJECTIVES: To compare the first-trimester uterine artery pulsatility index (PI) measured by abdominal and transvaginal ultrasound (US). METHODS: We performed a prospective study of singleton pregnant women recruited at 11 to 13 weeks' gestation. The mean uterine artery PI was obtained by abdominal followed by transvaginal US. The mean of the left and right uterine artery PIs was used, and differences between approaches were computed. The intraclass correlation coefficient and a Bland-Altman plot were used to compare the two approaches. RESULTS: Data were available for 940 participants, including 928 (99%) with uterine artery PIs obtained on both uterine sides. The mean uterine artery PI decreased with gestational age in both approaches (P < .001). We observed a moderate correlation between abdominal and transvaginal mean uterine artery PIs (intraclass correlation coefficient, 0.72; 95% confidence interval, 0.69 to 0.75). Values obtained by abdominal US (median, 1.70, interquartile range, 1.35 to 2.09) were greater than those obtained by transvaginal US (median, 1.65; interquartile range, 1.37 to 1.99). There was a significant increase in differences as average measurements became higher (P < .01). CONCLUSIONS: The first-trimester mean uterine artery PI decreases with gestational age in both approaches. Abdominal US could be associated with greater uterine artery PI values than transvaginal US, especially at higher measurements. The first-trimester uterine artery PI for prediction of adverse perinatal outcomes should be adjusted for gestational age and possibly for the US approach.

First-trimester placental thickness and the risk of preeclampsia or SGA.

INTRODUCTION: Placental thickness in the second trimester of pregnancy has been associated with risks of placenta-mediated complications of pregnancy. We aimed to estimate the association between first-trimester maximum placental thickness and the subsequent risk of preeclampsia and/or the delivery of small-for-gestational-age (SGA) neonate. METHODS: Prospective cohort study of women recruited at 11-14 weeks gestation. Placental thickness was measured at its apparent center and reported in multiple of median (MoM) adjusted for gestational age. Participants were followed until delivery for pregnancy outcomes. Placental measurements of participants who developed preeclampsia and/or delivered SGA neonate (defined as birth weight below 10th percentile) were compared with those who did not using non-parametric statistical analyses. RESULTS: We recruited 991 participants at a mean gestational age of 12.7 ± 0.7 weeks of gestation. SGA (n = 52) was associated with reduced 1st trimester placental thickness (median: 0.89 MoM; interquartile (IQ): 0.75-1.02 vs 0.98 MoM; IQ: 0.84-1.15; p < 0.01). Pregnancies that developed preeclampsia (n = 20) tended to have greater placental thickness (median: 1.10 MoM; IQ: 0.93-1.25 vs 0.97 MoM; IQ: 0.84-1.14; p = 0.06) with values > 1.2 MoM significantly increasing the risk for preeclampsia (relative risk: 3.6; 95%CI: 1.5-8.6, p < 0.01). Pregnancies complicated by both SGA and preeclampsia (n = 5) had similar placental thickness in the first-trimester in comparison with uncomplicated pregnancies (median: 1.03 MoM; IQ: 0.89-1.42 vs 0.98 MoM; IQ: 0.84-1.14; p = 0.33). CONCLUSION: First-trimester placental thickness diverges in pregnancies at risk of preeclampsia (increased) or SGA (decreased), but remains within normal values in pregnancies at risk of both conditions, suggesting that the underlying pathologies have some opposing effects on early placental growth. The current findings should be validated in a larger cohort.

Single versus double-layer uterine closure at cesarean: impact on lower uterine segment thickness at next pregnancy.

BACKGROUND: Uterine rupture is a potential life-threatening complication during a trial of labor after cesarean delivery. Single-layer closure of the uterus at cesarean delivery has been associated with an increased risk of uterine rupture compared with double-layer closure. Lower uterine segment thickness measurement by ultrasound has been used to evaluate the quality of the uterine scar after cesarean delivery and is associated with the risk of uterine rupture. OBJECTIVE: To estimate the impact of previous uterine closure on lower uterine segment thickness. STUDY DESIGN: Women with a previous single low-transverse cesarean delivery were recruited at 34-38 weeks' gestation. Transabdominal and transvaginal ultrasound evaluation of the lower uterine segment thickness was performed by a sonographer blinded to clinical data. Previous operative reports were reviewed to obtain the type of previous uterine closure. Third-trimester lower uterine segment thickness at the next pregnancy was compared according to the number of layers sutured and according to the type of thread for uterine closure, using weighted mean differences and multivariate logistic regression analyses. RESULTS: Of 1613 women recruited, with operative reports available, 495 (31%) had a single-layer and 1118 (69%) had a double-layer closure. The mean third-trimester lower uterine segment thickness was 3.3 ± 1.3 mm and the proportion with lower uterine segment thickness <2.0 mm was 10.5%. Double-layer closure of the uterus was associated with a thicker lower uterine segment than single-layer closure (weighted mean difference: 0.11 mm; 95% confidence interval [CI], 0.02 to 0.21 mm). In multivariate logistic regression analyses, a double-layer closure also was associated with a reduced risk of lower uterine segment thickness <2.0 mm (odd ratio [OR], 0.68; 95% CI, 0.51 to 0.90). Compared with synthetic thread, the use of catgut for uterine closure had no significant impact on third-trimester lower uterine segment thickness (WMD: -0.10 mm; 95% CI, -0.22 to 0.02 mm) or on the risk of lower uterine segment thickness <2.0 mm (OR, 0.95; 95% CI, 0.67 to 1.33). Finally, double-layer closure was associated with a reduced risk of uterine scar defect (RR, 0.32; 95% CI, 0.17 to 0.61) at birth. CONCLUSION: Compared with single-layer closure, a double-layer closure of the uterus at previous cesarean delivery is associated with a thicker third-trimester lower uterine segment and a reduced risk of lower uterine segment thickness <2.0 mm in the next pregnancy. The type of thread for uterine closure has no significant impact on lower uterine segment thickness.

High-flavanol and high-theobromine versus low-flavanol and low-theobromine chocolate to improve uterine artery pulsatility index: a double blind randomized clinical trial.

OBJECTIVE: To evaluate the impact of high-flavanol and high-theobromine (HFHT) chocolate in women at risk of preeclampsia (PE). STUDY DESIGN: We conducted a single-center randomized controlled trial including women with singleton pregnancy between 11 and 14 weeks gestation who had bilateral abnormal uterine artery (UtA) waveforms (notching) and elevated pulsatility index (PI). Participants were randomized to either HFHT or low-flavanol and low-theobromine (LFLT) chocolate (30 grams daily for a total of 12 weeks). UtA PI, reported as multiple of medians (MoM) adjusted for gestational age, was assessed at baseline and 12 weeks after randomization. RESULTS: One hundred thirty-one women were randomized with mean gestational age of 12.4 ± 0.6 weeks and a mean UtA PI of 1.39 ± 0.31 MoM. UtA PI adjusted for gestational age significantly decreased from baseline to the second visit (12 weeks later) in the two groups (p < 0.0001) but no significant difference was observed between the groups (p = 0.16). CONCLUSIONS: Compared with LFLT chocolate, daily intake of HFHT chocolate was not associated with significant changes of UtA PI. Nevertheless, the improvement observed in both groups suggests that chocolate could improve placental function independently of flavanol and/or theobromine content.

Reliability of First-Trimester Ultrasonic Biopsy for the Evaluation of Placental and Myometrial Blood Perfusion and the Prediction of Preeclampsia.

OBJECTIVE: Low placental vascularization measured by three-dimensional (3-D) ultrasound with power Doppler can predict preeclampsia. We evaluated the reliability and reproducibility of the ultrasonic sphere biopsy (USSB) technique to evaluate placental and subplacental myometrium vascularization in the first trimester. METHODS: We performed a secondary analysis of a case-control study nested in a prospective cohort of women with a singleton pregnancy undergoing ultrasound at 11 to 14 weeks' gestation. Women who developed preeclampsia (n = 20) and randomly selected controls (n = 60) were compared. Other controls (n = 60) were also randomly selected to evaluate intra- and inter-observer reproducibility. Using 3-D power Doppler, the vascularization index (VI), flow index (FI), and vascularization flow index (VFI) were measured from the volume of the whole placenta and the subplacental myometrium and from their respective USSB. Pearson's correlation coefficients (cc) with their P-values were calculated. RESULTS: We observed that USSB is reliable in estimating the vascularization of the whole placenta in the first trimester (cc of VI 0.83; of FI 0.62; and of VFI 0.78; P < 0.001 for all) but was not as reliable for estimating subplacental myometrium vascularization (cc of VI 0.71; of FI 0.35; and of VFI 0.73). Measurement of placental vascularization using USSB showed good to excellent intra- and inter-observer reproducibility (cc of VI 0.86 and 0.85, respectively; of FI 0.75 and 0.75, respectively; and of VFI 0.83 and 0.83, respectively; P < 0.001 for all). Finally, we observed that women who subsequently developed preeclampsia had lower placental USSB VI (2.1 vs 4.8, P = 0.02), FI (32.4 vs. 42.5, P = 0.002), and VFI (0.8 vs. 2.1, P = 0.01) than controls. CONCLUSION: First-trimester USSB of the placenta using 3-D power Doppler is a reliable and reproducible procedure for estimating placental vascularization and could be used to predict preeclampsia.

Could High Volume of Physical Activities in Early Pregnancy Interfere with Deep Placentation?

Background The impact of physical activity (PA) during pregnancy on obstetrical outcomes remains controversial. We followed pregnant women who reported more than 3 hours of sustained PA per week during the first trimester of pregnancy. Cases Total five eligible women were followed. We observed small placenta from the first trimester (median: 0.68; interquartile [IQ]: 0.62-0.97 multiples of median [MoM]) to delivery (median: 0.82; IQ: 0.71-0.94 MoM), high uterine artery pulsatility index in the first (median: 1.82; IQ: 1.68-1.99 MoM) and second trimesters (median: 1.33; IQ: 1.11-1.56 MoM) of pregnancy. Placenta pathology revealed deep vasculopathy in three (60%) cases. However, all participants delivered at term and none of them experienced preeclampsia. Conclusion This small case series suggest that high PA volume in first trimester could interfere with deep placentation.

Lower uterine segment thickness to prevent uterine rupture and adverse perinatal outcomes: a multicenter prospective study.

BACKGROUND: Choice of delivery route after previous cesarean delivery can be difficult because both trial of labor after cesarean delivery and elective repeat cesarean delivery are associated with risks. The major risk that is associated with trial of labor after cesarean delivery is uterine rupture that requires emergency laparotomy. OBJECTIVE: This study aimed to estimate the occurrence of uterine rupture during trial of labor after cesarean delivery when lower uterine segment thickness measurement is included in the decision-making process about the route of delivery. STUDY DESIGN: In 4 tertiary-care centers, we prospectively recruited women between 34 and 38 weeks of gestation who were contemplating a vaginal birth after a previous single low-transverse cesarean delivery. Lower uterine segment thickness was measured by ultrasound imaging and integrated in the decision of delivery route. According to lower uterine segment thickness, women were classified in 3 risk categories for uterine rupture: high risk (<2.0 mm), intermediate risk (2.0-2.4 mm), and low risk (≥2.5 mm). Our primary outcome was symptomatic uterine rupture, which was defined as requiring urgent laparotomy. We calculated that 942 women who were undergoing a trial of labor after cesarean delivery should be included to be able to show a risk of uterine rupture <0.8%. RESULTS: We recruited 1856 women, of whom 1849 (99%) had a complete follow-up data. Lower uterine segment thickness was <2.0 mm in 194 women (11%), 2.0-2.4 mm in 217 women (12%), and ≥2.5 mm in 1438 women (78%). Rate of trial of labor was 9%, 42%, and 61% in the 3 categories, respectively (P<.0001). Of 984 trials of labor, there were no symptomatic uterine ruptures, which is a rate that was lower than the 0.8% expected rate (P=.0001). CONCLUSION: The inclusion of lower uterine segment thickness measurement in the decision of the route of delivery allows a low risk of uterine rupture during trial of labor after cesarean delivery.

Impact of uterine closure on residual myometrial thickness after cesarean: a randomized controlled trial.

BACKGROUND: Incomplete healing of uterine scar after cesarean has been associated with adverse gynecological and obstetrical outcomes. Several studies reported that uterine closure at cesarean influences the healing of uterine scar and the risk of uterine rupture at subsequent pregnancies: the commonly used locked single-layer suture including the decidua being associated with a 4-fold increased risk of uterine rupture. However, data from randomized trials are lacking. OBJECTIVE: We sought to evaluate the impact of 3 techniques of uterine closure after cesarean delivery on uterine scar healing. STUDY DESIGN: This was a 3-arm 1:1:1 randomized study in women with singleton pregnancies undergoing elective primary cesarean delivery at ≥38 weeks' gestation. Closure of the uterine scar was carried out by locked single layer including the decidua, double layer with locked first layer including the decidua, or double layer with unlocked first layer excluding the decidua. Primary outcome was residual myometrial thickness (RMT) at the site of the scar, measured by transvaginal ultrasound 6 months after delivery. Secondary outcome was the RMT as a percentage of the myometrial thickness above the scar (healing ratio). Intent-to-treat analyses using Student t test were performed to compare each double-layer technique to the single-layer closure, and P < .025 was considered significant. RESULTS: Complete follow-up was obtained from 73 (90%) of the 81 participants. Compared to single-layer closure, double-layer closure with unlocked first layer was associated with thicker RMT (3.8 ± 1.6 mm vs 6.1 ± 2.2 mm; P < .001) and greater healing ratio (54 ± 20% vs 73 ± 23%; P = .004). In contrast, double-layer closure with locked first layer was not significantly different than single-layer closure in either RMT (4.8 ± 1.3; P = .032) or healing ratio (60 ± 21%; P = .287). CONCLUSION: Double-layer closure with unlocked first layer is associated with better uterine scar healing than locked single layer.

First-Trimester Placental and Myometrial Blood Perfusion Measured by Three-Dimensional Power Doppler in Preeclampsia.

OBJECTIVE: The study aims to evaluate first-trimester vascularization of the placenta and subplacental myometrium in women who subsequently develop preeclampsia. STUDY DESIGN: A case-control study nested in a prospective cohort was conducted in women with singleton pregnancy between 11 and 14 weeks' gestation. Three-dimensional standardized acquisition of the placenta and subplacental myometrium volumes with and without power Doppler was undertaken, and all participants were followed up until delivery. Each woman diagnosed with preeclampsia was matched with three controls who delivered at term without pregnancy complications. First-trimester volume, vascularization index (VI), flow index (FI), and vascular flow index (VFI) of the entire placenta and subplacental myometrium were measured separately. The results were stratified for preterm and term preeclampsia, respectively. RESULTS: A total of 1,034 women were recruited, including 16 (1.5%) who developed term preeclampsia and 4 (0.4%) who developed preterm preeclampsia. Preeclampsia was associated with a significantly lower placental VI, placental VFI, subplacental VI, and subplacental VFI in the first trimester than with the controls (all p < 0.05). All cases (4/4) of preterm preeclampsia, 56% (9/16) of term preeclampsia, and 28% (17/60) of the controls had a subplacental VI below 18% (p < 0.01). CONCLUSION: First-trimester placental and subplacental myometrium vascularizations are significantly reduced in women who subsequently develop preeclampsia.