Uterine artery Doppler velocimetry at 11-14 weeks in singleton pregnancies conceived by assisted reproductive technology

Fetal Growth Velocity according to the Mode of Assisted Conception

INTRODUCTION

Pregnancies conceived through assisted reproductive techniques (ARTs) are on the rise worldwide and have been associated with a higher risk of placental-related disease in the third trimester.

METHODS

A cohort was created of singleton pregnancies after assisted reproduction, admitted at our institution for delivery, between January 2020 and August 2022. Fetal growth velocity from the second trimester to delivery was compared against a gestational-age-matched group of pregnancies spontaneously conceived according to the origin of the selected oocyte (i.e., autologous vs. donated).

RESULTS

125 singleton pregnancies conceived through ART were compared to 315 singleton spontaneous conceptions. Overall, after adjusting for possible confounders, multivariate analysis demonstrated that ART pregnancies had a significantly lower estimated fetal weight (EFW) z-velocity from the second trimester to delivery (adjusted mean difference = -0.002; p = 0.035) and a higher frequency of EFW z-velocity in the lowest decile (adjusted OR = 2.32 [95% CI, 1.15-4.68]). Also, when ART pregnancies were compared according to the type of oocyte, those conceived with donated oocytes showed a significantly lower EFW z-velocity from the second trimester to delivery (adjusted mean difference = -0.008; p = 0.001) and a higher frequency of EFW z-velocity in the lowest decile (adjusted OR = 5.33 [95% CI, 1.34-21.5]).

CONCLUSIONS

Pregnancies achieved through ART exhibit a pattern of lower growth velocity across the third trimester, especially those conceived with donated oocytes. The former represents a sub-group at the highest risk of placental dysfunction that may warrant closer follow-up.

The association between assisted reproductive technology and cardiac remodeling in fetuses and early infants: a prospective cohort study

BACKGROUND

Limited data exist regarding the potential impact of assisted reproductive technology (ART) on cardiac remodeling. In particular, whether different ART techniques are related to different cardiac alterations remains unclear. We aimed to evaluate cardiac changes in fetuses and infants arising from ART and fetal cardiac alterations in fetuses conceived by specific ART procedures.

METHODS

This prospective and observational cohort study recruited 111 fetuses conceived by ART and 106 spontaneously conceived controls between December 2017 and April 2019. Echocardiography was performed between 28⁺⁰ and 32⁺⁶ weeks-of-gestation and at 0-2 and 6 months after birth.

RESULTS

A total of 88 ART fetuses and 85 controls were included in the final analysis. Compared to controls, ART fetuses demonstrated a globular enlarged left ventricle (LV) (LV sphericity index of mid-section, 2.29 ± 0.34 vs. 2.45 ± 0.39, P = 0.006; LV area, 262.33 ± 45.96 mm² vs. 244.25 ± 47.13 mm², P = 0.002), a larger right ventricle (RV) (RV area, 236.10 ± 38.63 mm² vs. 221.14 ± 42.60 mm², P = 0.003) and reduced LV systolic deformation (LV global longitudinal strain (GLS), -19.56% ± 1.90% vs. -20.65% ± 1.88%, P = 0.013; LV GLS rate S, -3.32 ± 0.36 s^-1 vs. -3.58 ± 0.39 s^-1, P = 0.023). There were no significant differences between the ART and control groups at postnatal follow-ups. Furthermore, we found fetal cardiac morphometry and function were comparable between different ART procedures. Compared to controls, the fetuses derived from various ART procedures all exhibited impairments in the LV GLS and the LV GLS rate S.

CONCLUSIONS

Our analysis demonstrated that subclinical cardiac remodeling and dysfunction were evident in ART fetuses, although these alterations did not persist in early infancy. In addition, various ART procedures may cause the same unfavorable changes in the fetal heart.

TRIAL REGISTRATION

This trial was registered at the Chinese Clinical Trial Registry ( www.chictr.org.cn ) ( ChiCTR1900021672 ) on March 4, 2019, retrospectively registered.

Prospective longitudinal cohort study of uterine arteries Doppler in singleton pregnancies obtained by IVF/ICSI with oocyte donation or natural conception

STUDY QUESTION

Do uterine arteries Doppler studies show different pulsatility index (UtA-PI) measurements in IVF/ICSI pregnancies with oocyte donation (OD) as compared to natural conceptions?

SUMMARY ANSWER

In IVF/ICSI pregnancies with OD, UtA-PI is reduced by an average of about 40% as compared to pregnancies with natural conception.

WHAT IS KNOWN ALREADY

OD pregnancies present worse pregnancy outcomes as compared to natural conception, particularly for increased incidence of pre-eclampsia (PE). Recent evidence shows that IVF/ICSI pregnancies with frozen blastocyst transfer also present higher prevalence of PE and 15% lower UtA-PI as compared to pregnancies after fresh blastocyst transfers.

STUDY DESIGN, SIZE, DURATION

Prospective, longitudinal matched cohort study performed in the Fetal Medicine and Obstetric Departments of San Raffaele Hospital in Milan, between 2013 and 2018. The analysis is based on 584 Doppler observations collected from 296 women with different method of conception (OD n = 122; natural conception n = 174).

PARTICIPANTS/MATERIALS, SETTING, METHODS

IVF/ICSI viable singleton pregnancies with OD and natural conception control pregnancies matched for BMI and smoking, performing repeated UtA-PI measurements at 11-34 weeks. Miscarriages, abnormalities, twins, significant maternal diseases and other types of ARTs were excluded. Log mean left-right UtA-PI was used for analysis with linear mixed model (LMM) and correction for significant confounders. Pregnancy outcome was also analyzed.

MAIN RESULTS AND THE ROLE OF CHANCE

Participants after OD were older and more frequently nulliparous (mean age: OD 43.4, 95% CI from 42.3 to 44.6; natural conception 35.1, 95% CI from 34.5 to 35.7; P-value < 0.001; nulliparous: OD 96.6%; natural conception 56.2%; P-value < 0.001). Mean pulsatility index was lower in OD (UtA-PI: natural conception 1.22; 95% CI from 1.11 to 1.28; OD 1.04; 95% CI from 0.96 to 1.12; P-value < 0.001). A significant effect of parity, gestational age (GA) modeled with a cubic polynomial and BMI was described in the LMM. The mean Log UtA-PI was on average 37% lower in OD as compared to natural conception pregnancies at LMM (P-value < 0.001). We also found a significant interaction between longitudinal UtA-PI Doppler and GA. Therefore, at 11 weeks' gestation the Log UtA-PI was 42% lower and, at 34 weeks, the differences reduced to 32%. GA at delivery and birth weight were statistically lower in OD group; however, birthweight centile was not statistically different. Preeclampsia was 11-fold more common in the OD group (0.6% and 6.6%, P-value = 0.003). No other significant difference in pregnancy outcome was shown in the study groups (gestational diabetes mellitus, small or large for GA).

LIMITATIONS, REASONS FOR CAUTION

It was not possible to properly match for maternal age and to blind the assessment given the major differences between cohorts; however, we did not find significant within-groups effects related to maternal age. Future research is needed to reassess outcomes and correct them for maternal characteristics (e.g. cardiovascular function).

WIDER IMPLICATIONS OF THE FINDINGS

This finding reproduces our previous discovery of lower UtA-PI in frozen as compared to fresh blastocyst transfer. The vast majority of OD is obtained by the use of cryopreservation. We speculate that increased uterine perfusion may be the physiological response to compensate dysfunctions both in the mother and in the placenta.

STUDY FUNDING/COMPETING INTEREST(S)

This is a non-funded study. The authors do not declare competing interest.

TRIAL REGISTRATION NUMBER

N/A.

Uterine artery Doppler in singleton pregnancies conceived after in-vitro fertilization or intracytoplasmic sperm injection with fresh vs frozen blastocyst transfer: longitudinal cohort study

OBJECTIVE

Pregnancies conceived by frozen blastocyst transfer (FBT) have higher gestational age and weight at birth as compared to those derived by fresh blastocyst transfer. The aim of this study was to evaluate uterine artery pulsatility index (UtA-PI) in pregnancies conceived by in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) techniques using fresh vs cryopreserved blastocysts.

METHODS

This was a prospective longitudinal study of viable singleton IVF/ICSI pregnancies conceived after FBT or fresh blastocyst transfer, that underwent serial ultrasound assessment at San Raffaele Hospital, Milan, Italy at 7-37 gestational weeks. We excluded pregnancies conceived using other assisted reproductive techniques such as egg donation, twin gestation, pregnancy with abnormality and those resulting in miscarriage. Pregnant women underwent ultrasound assessment at 7-10, 11-14, 18-25 and 26-37 weeks' gestation. Mean UtA-PI was measured using Doppler ultrasound according to The Fetal Medicine Foundation criteria. Pregnancy outcomes were recorded. The primary outcome was mean UtA-PI measurement and secondary outcomes were gestational age at birth, birth weight and fetal and maternal complications, including small-for-gestational age (SGA), pre-eclampsia and large-for-gestational age. UtA-PI values were made Gaussian after log₁₀ transformation. Analysis of repeated measures using a multilevel linear mixed model (fixed effects and random effects) was performed. The possible effect of other covariates on UtA-PI Doppler values, including body mass index, SGA and pre-eclampsia, was also evaluated.

RESULTS

A total of 367 IVF/ICSI cycles, comprising 164 with fresh blastocyst transfer and 203 with FBT, were included and a total of 625 observations (median, 2.5 (range, 1-4)) were collected and analyzed. The FBT group had on average 14% lower UtA-PI compared with the fresh-blastocyst-transfer group. In pregnancies with SGA fetuses, UtA-PI was 18% higher compared to pregnancies without, irrespective of the study group. Pregnancies that underwent fresh blastocyst transfer had significantly lower birth-weight centile (43.4 ± 23.3 vs 50.0 ± 23.1; P = 0.007) and a higher rate of SGA (7.9% vs 2.0%; P = 0.008) compared to those that underwent FBT. No significant differences were found between the two groups with respect to gestational age at birth and rates of preterm birth, pre-eclampsia, gestational diabetes mellitus and large-for-gestational age.

CONCLUSION

UtA-PI and the proportion of SGA are lower in IVF/ICSI pregnancies conceived after FBT as compared to fresh blastocyst transfer. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

The Number of Circulating Fetal Extravillous Trophoblasts Varies from Gestational Week 6 to 20

Cell-based non-invasive prenatal testing (cbNIPT) based on circulating fetal extravillous trophoblasts (fEVTs) has shown to be possible in gestational week (GW) 10–13. Prenatal testing is relevant for a wider time period than GW 10–13, but it is unclear if fEVTs are present in sufficient numbers for cbNIPT at other time points during pregnancy. We present the first longitudinal study where the number of circulating fEVTs was determined from the mid first trimester to the mid second, specifically GW 6–8, 12–13, and 19–20. Blood samples from 13 women opting for assisted reproduction were collected at GW 6–8, 12–13, and 19–20. fEVTs were enriched using a magnetic-activated cell sorting system, stained with anti-cytokeratin antibodies, and fEVTs were identified with the use of a MetaSystem fluorescence microscope scanner. Blood samples drawn at GW 6–8 yielded an average of 5.5 fEVTs per 30 mL of blood. This increased significantly to an average of 11.8 in GW 12–13 (P value: 0.0070, Mann-Whitney test), and decreased significantly to an average of 5.3 in GW 19–20 (P value: 0.0063, Mann-Whitney test). In 9 out of 13 cases, the number of fEVTs peaked in GW 12–13 compared to GW 6–8 and GW 19–20. For the majority of cases, fEVTs can be identified at GW 6–8 and GW 19–20, but the highest number of fEVTs is observed at GW 12–13 indicating this is the optimal time point for cbNIPT.

IVF/ICSI treatment and the risk of iatrogenic preterm birth in singleton pregnancies: systematic review and meta-analysis of cohort studies

Objectives: Preterm birth (PTB) is more frequent among in vitro fertilization (IVF) as compared to natural conception and recent research in this group describes an increase of its spontaneous etiology. However, clear description and quantification of iatrogenic preterm birth (IPTB) was not determined in IVF/ICSI (intra-cytoplasmic sperm injection) conceptions. This study quantifies the risk of IPTB in singleton pregnancies resulting from IVF/ICSI as compared to spontaneous conceptions (SCs).Methods: Web-based databases search (PubMed/Medline, Scopus, Web of Science) from inception up to January 2019 looking for cohort studies comparing the risk of IPTB in singleton pregnancies obtained with IVF/ICSI (intervention group) or SC (control group). Only studies with clear distinction of spontaneous and indicated PTB were included. Primary outcome was IPTB before 37 weeks of gestation, defined as indicated delivery for any medical recommendation. All pertinent secondary outcomes were also included: IPTB <34/32/28 weeks, abnormal cardiotocography (CTG), abruptio, placenta previa, pre-eclampsia, fetal growth restriction, any other available indication to IPTB. A meta-analysis calculated the pooled odds ratio (OR) for IPTB in IVF/ICSI and SC, using random effects model. Sensitivity analysis for study quality, methodology of case counting, use of cryotransfer, and secondary analyses for available indications of IPTB were also performed. Prospero RN: CRD42019117672.Results: Pooled crude analysis showed a sample size of 9590 births with significant increase in IPTB <37 weeks in IVF/ICSI pregnancies (nine studies, pooled proportion IPTB IVF/ICSI 4.73% vs. SC 1.81%; OR = 2.47; 95% CI: 1.46-4.18; I² = 67%). Pooled analysis was impossible for most secondary outcomes due to lack of available data and failed to show statistical significance for abnormal CTG. The risk for IPTB due to abruptio placentae or placenta previa was significantly increased in IVF/ICSI pregnancies (two studies, 561 pregnancies; pooled proportion IPTB IVF/ICSI 2.12% vs. SC 1.06%; OR = 5.41; 95% CI: 1.26-23.25; I²: 0%).Conclusion: The risk of IPTB <37 weeks in singleton pregnancies achieved after IVF/ICSI is significantly greater than that occurring in SC. This is likely due to a multifactorial etiology, in which placental diseases are included. Full etiologic understanding of this association needs further clarification.Summary: The risk of IPTB below 37 weeks in singleton pregnancies achieved after IVF/ICSI is more than double than that occurring in natural conception.

Assisted reproductive technology and the risk of preeclampsia: an updated systematic review and meta-analysis

Background

The objective of this systematic review and meta-analyses was to assess the risk of preeclampsia among women who conceived with assisted reproductive technology (ART).

Methods

We searched the ISI Web of Knowledge, Medline/PubMed, Scopus, and Embase (from inception to May 2017) for English language articles using a list of key words. In addition, reference lists from identified studies and relevant review articles were also searched. Data extraction was performed by two authors, and the study quality was assessed using the Newcastle–Ottawa Scale. Random-effects model meta-analysis was applied to pool the relative risks (RR) across studies.

Results

A total of 48 studies (5 case-control studies and 43 cohort studies) were included in this meta-analysis. The Cochran Q test and I² statistics revealed substantial heterogeneity (Q = 26,313.92, d.f. = 47, p < 0.001 and I² = 99.8%). Meta-analysis showed a significant increase in preeclampsia in women who conceived by ART compared with those who conceived spontaneously (RR = 1.71, 95% CI = 1.11–2.62, p = 0.015).

Conclusions

The findings of this systematic review indicate that the use of ART treatment is associated with a 1.71-fold increase in preeclampsia.

Placental volume and other first-trimester outcomes: are there differences between fresh embryo transfer, frozen-thawed embryo transfer and natural conception?

RESEARCH QUESTION

Does mode of conception influence placental volume and other first-trimester outcomes?

DESIGN

This retrospective single-centre case-control study led in Dijon University Hospital included 252 singleton pregnancies (84 IVF with either fresh embryo transfer or frozen-thawed embryo transfer [FET] and 168 natural conceptions). First-trimester placental volume, uterine artery pulsatility index and maternal serum PAPP-A and beta-HCG were measured. Statistical analyses were adjusted for gestational age, the newborn's gender, maternal age, parity, body mass index and smoking status.

RESULTS

Placental volume was significantly greater in the FET group than in the control group (P = 0.043) and fresh embryo transfer (P = 0.023) groups. At birth, fresh embryo transfer newborns were significantly smaller than controls (P = 0.01) and FET newborns (P = 0.008). Postpartum haemorrhage was far more frequent in FET than in controls and fresh embryo transfer group (38.1%, 2.6% and 1.9%, respectively; P < 0.0001). Placental volume positively correlated with PAPP-A, beta-HCG and the newborn's birth weight, and negatively correlated with uterine artery pulsatility index.

CONCLUSIONS

Placental volume and other first-trimester parameters are modified by IVF with fresh embryo transfer and FET compared with natural conception, but with opposite trends. Given the different protocols used for these techniques, hormonal treatment per se may have a major effect on pregnancy outcomes through the modification of placental invasiveness.

Uterine artery Doppler pulsatility index at 11-38 weeks in ICSI pregnancies with egg donation

BACKGROUND

Uterine artery Doppler pulsatility index (UtA-PI) may be different in pregnancies with egg donation (ICSI-ED) as compared to conceptions with autologous intra-cytoplasmatic sperm injection (autologous ICSI) and to spontaneous conceptions (SC).

METHODS

One hundred and ninety-four pregnant women with different modes of conception (MC) were prospectively evaluated: 53 ICSI-ED, 36 autologous ICSI and 105 SC. To evaluate the effects of different MC on PI, multivariable linear regression (MLR) models predicting UtA-PI were fitted after adjustment for maternal age, body mass index, race, parity, smoking status and gestational age.

RESULTS

In the first trimester, at MLR, autologous ICSI was not associated with a significantly different UtA-PI [estimate (EST) 0.01; 95% confidence interval (CI) -0.19, 0.2; P=0.9] when compared to SC. Conversely, MC by ICSI-ED was associated with lower first trimester UtA-PI (EST -0.32; CI -0.55, -0.08; P=0.01) when compared to SC. At MLR, MC by autologous ICSI and by ICSI-ED were not associated with significant differences in the second and third trimester UtA-PI when compared to SC.

CONCLUSION

ICSI-ED conception presented lower UtA-PI when compared to SC at 11+0-13+6 weeks but not at later assessments. Correction of UtA-PI measurement specifying the origin of oocyte may be useful in first trimester screening.

Nuchal translucency measurement, free β-hCG and PAPP-A concentrations in IVF/ICSI pregnancies: systematic review and meta-analysis

So far, data on the effect of assisted reproductive technologies (ART) on the components of first trimester combined screening for Down syndrome are still controversial. A systematic search of the literature was performed in order to identify the effect of ART, particularly in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) with fresh embryo transfer, on the nuchal translucency, free beta-human chorionic gonadotrophin and pregnancy-associated plasma protein-A measurements. Moreover, a meta-analysis and a descriptive graphical representation of the ratios between ART and spontaneous pregnancies (controls) values of median of the multiple of median (m₀ MoM) were performed. Free beta-human chorionic gonadotrophin test showed slightly higher values in the ICSI group than controls (RR = 1.09, 95%CI: 1.03-1.16) but not in the IVF group (RR = 1.03, 95%CI: 0.94-1.12). Pregnancy-associated plasma protein-A values for IVF/ICSI, IVF and ICSI showed lower values in comparison with controls (RR, 95%CI 0.85, 0.80-0.90; 0.82, 0.74-0.89 and 0.83, 0.79-0.86, respectively). The nuchal translucency measurement did not show any statistical differences between study groups (IVF and ICSI) and controls (RR = 1.00, 95%CI: 0.94-1.08 and RR = 1.01, 95%CI: 0.97-1.05, respectively). These results may be due to alterations in the placentation of ART pregnancies. Differentiating further subgroups of ART pregnancies may explain the differences in biomarker concentrations, in prenatal behavior and in obstetric outcomes between ART and spontaneous pregnancies. © 2017 John Wiley & Sons, Ltd.

Are There Differences in Placental Volume and Uterine Artery Doppler in Pregnancies Resulting From the Transfer of Fresh Versus Frozen-Thawed Embryos Through In Vitro Fertilization

OBJECTIVE

To compare uterine artery pulsatility index (PI) and 3-dimensional (3D) placental volume values in first-trimester pregnancies conceived naturally or through in vitro fertilization (IVF) technique using either fresh or cryopreserved embryo and to relate these measurements with preeclampsia (PE) development.

METHODS

Uterine artery PI and placental volume were measured at 11 + 0 to 13 + 6 weeks of gestation in 266 IVF pregnancies (139 women with fresh embryo and 127 women with frozen-thawed embryo transfer) and in 266 spontaneously conceived pregnancies matched for maternal age. Nulliparous women with singleton pregnancies were recruited. The mean, highest, and lowest uterine artery PI and placental volume values measured were converted to multiples of the expected normal median (MoM) adjusted for gestational age. The MoM values of IVF pregnancies were compared with those of the naturally conceived group and related to PE development.

RESULTS

No differences were found in uterine artery PI MoM between the 3 groups. Placental volume was significantly lower than in both IVF groups when compared to the controls (fresh embryo IVF Z = 9.33; P ≤ .0001; frozen-thawed embryos IVF Z = 3.1; P = .04). The IVF pregnancies with fresh embryos showed placental volume MoM values significantly lower than in the frozen-thawed embryo IVF pregnancies (U = 5.4; P ≤ .0001). In fresh embryo IVF pregnancies developing PE placental volume values resulted lower than in the normotensive ones (U = 2.11; P = .03), while no differences were found for uterine artery PI values.

CONCLUSION

First-trimester placental volume, as assessed by 3D ultrasound, is reduced in IVF pregnancies, and these differences are more marked in those obtained with fresh embryos than those obtained with cryopreservation. This may explain the better obstetrical and perinatal outcomes occurring with the former technique.

Placental volume and uterine artery Doppler evaluation at 11 + 0 to 13 + 6 weeks' gestation in pregnancies conceived with in-vitro fertilization: comparison between autologous and donor oocyte recipients

OBJECTIVE

To compare first-trimester uterine artery pulsatility index (UtA-PI) and three-dimensional (3D) placental volume in pregnancies conceived through in-vitro fertilization (IVF) using autologous or donor oocytes and pregnancies conceived naturally, and to relate these measurements to the development of pre-eclampsia (PE).

METHODS

UtA-PI and placental volume were measured at 11 + 0 to 13 + 6 weeks of gestation in 416 IVF pregnancies (307 with autologous and 109 with donor oocytes) and in 498 spontaneously conceived pregnancies. We recruited nulliparous women with singleton pregnancy. The measured mean UtA-PI and placental volume values were converted to multiples of the expected normal median (MoM), adjusted for gestational age. MoM values of IVF pregnancies were compared with MoM values of the naturally conceived pregnancies and related to PE development.

RESULTS

Placental volume was significantly reduced in IVF pregnancies (K = 169.3; P < 0.0001) compared with natural pregnancies. No difference was found in UtA-PI MoM between the two groups. Among IVF pregnancies, significantly lower placental volumes were seen in those that received donor oocytes when compared with those with autologous oocytes (z = 3.89; P < 0.001). In IVF pregnancies that developed PE, lower values of placental volume were demonstrated with respect to normotensive pregnancies (donor: U = 6.8; P = 0.009; autologous: U = 5.1; P = 0.023), whereas no difference was found in UtA-PI. Multivariate logistic regression analysis demonstrated that placental volume (odds ratio (OR), 1.97 (95% CI, 1.33-2.27)) and donor oocytes in IVF pregnancy (OR, 2.24 (95% CI, 1.5-2.83)) were independent predictors of PE, whereas autologous oocytes in IVF pregnancy were not found to be significant in the model.

CONCLUSIONS

First-trimester placental volume, as assessed by 3D ultrasound, is reduced in IVF pregnancies and this reduction is more marked in those involving donor oocyte recipients. The relative decrease in placental volume in IVF pregnancies that developed PE suggests an etiological mechanism different from uterine perfusion in such patients. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Reproductive performance: at the cross-road of genetics, technologies and environment

Sexual reproduction depends on a negotiation between the sexes at the level of the cells (gametes), tissue (trophectoderm of the blastocyst and endometrium in the uterus) and organisms (to allow sexual intercourse). This review evaluates new questions linked to sexual reproduction in the biosphere in the context of the 21st century, in light of current knowledge in genetics and epigenetics. It presents the challenge of ‘forcing reproductive efficiency’ using ineffective gametes, or despite other fertility problems, through medically assisted reproduction and presents the reproductive challenge of high production farm animals, which are in a situation of chronically negative energy balance. It also analyses the situation created by the release of endocrine disruptors into the environment and discusses the possible transgenerational consequences of environmental modifications linked to these compounds.

First trimester trophoblast and placental bed vascular volume measurements in IVF or IVF/ICSI pregnancies

STUDY QUESTION

Are first trimester trophoblast volume (TV) and placental bed vascular volume (PBVV) different in IVF or IVF/ICSI pregnancies in comparison with spontaneously conceived pregnancies?

SUMMARY ANSWER

Any possible abnormal placentation in IVF or IVF/ICSI pregnancies in comparison with spontaneously conceived pregnancies is not detected by a difference in PBVV or TV at an early gestational age (GA).

WHAT IS KNOWN ALREADY

Assisted reproductive technology pregnancies have been associated with an increased risk of placenta-related adverse pregnancy outcomes. It is unclear whether these effects originate from infertility or from the technique itself.

STUDY DESIGN, SIZE, DURATION

We performed a retrospective cohort study in which 154 pregnant patients qualified for participation.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Out of 154 pregnant patients, 84 conceived spontaneously and 70 conceived after IVF or IVF/ICSI. We determined the TV at 10 weeks GA by Virtual Organ Computer-aided AnaLysis measuring application and the PBVV at 12 weeks GA by the virtual reality operating system of BARCO I-Space in both subgroups. The investigators were blinded to the mode of conception during the measurements. Analysis was limited to singleton pregnancies with only one sac ever detectable.

MAIN RESULTS AND THE ROLE OF CHANCE

There were no differences in TV (mean 42.7, SD 15.9 versus mean 41.2, SD 13.9, P = 0.70) and PBVV (mean 27.6, SD 16.9 versus mean 24.8, SD 19.9, P = 0.20) between IVF or IVF/ICSI pregnancies and spontaneously conceived pregnancies. There was a significant correlation between TV and PBVV (rs = 0.283, P = 0.004).

LIMITATIONS, REASONS FOR CAUTION

The limitations of the present study concern the small size of the study groups.

WIDER IMPLICATIONS OF THE FINDINGS

IVF or IVF/ICSI does not seem to be associated with abnormal placentation.

STUDY FUNDING/COMPETING INTERESTS

This study was financially supported by the Erasmus Trustfonds, the Meindert de Hoop foundation and the Fonds NutsOhra. No competing interests are declared.

First trimester screening can predict adverse pregnancy outcomes

There has been an increasing drive over the last two decades to push the detection of women at risk of adverse pregnancy outcomes into the first trimester. This has led to a plethora of techniques, risk assessments and biomarkers, both fascinating and bewildering in its breadth. Despite the vast amount of knowledge available, it is often difficult to determine what is practicable and valuable for clinical practice. This is especially true as earlier diagnosis does not necessarily equate to improved outcomes for mother and child. We suggest that, at least for preeclampsia, fetal growth restriction, spontaneous preterm birth and gestational diabetes, there are effective first trimester tests available to identify the women at risk of subsequently developing complications. Unfortunately, there are no currently reliable first trimester tests available for identifying women at risk of stillbirth. It is likely that this field will continue to develop over time, and we hope that new and better strategies will continue to emerge to target these clinically important pathologies.

Assisted conception and placental perfusion assessed by uterine artery Doppler at 11-13 weeks' gestation

BACKGROUND

Pregnancies conceived by IVF are at increased risk of pre-eclampsia (PE). This study examines the potential mechanism for such association by examining the effect of method of conception on placentation as assessed by uterine artery Doppler at 11-13 weeks' gestation.

METHODS

This prospective screening study at 11(+0)-13(+6) weeks for PE in singleton pregnancies used a combination of maternal history and uterine artery pulsatility index (PI). Regression analysis was performed to examine the association between the method of conception and both uterine artery PI and development of PE, after adjustment for maternal characteristics and obstetric history.

RESULTS

In the study population of 27 461 pregnancies, conception was spontaneous in 26 538 (96.6%), by IVF in 426 (1.6%) and by use of ovulation induction (OI) drugs in 497 (1.8%) pregnancies. Conception by IVF was associated with an increase in risk for early-PE, requiring delivery before 34 weeks [odds ratio 3.94, 95% confidence interval (CI) 1.51-10.27] but not for late-PE. In the OI group, the risk of early- and late-PE was not increased. In addition to IVF, other significant contributors to the prediction of early-PE were maternal weight, height, African and South Asian racial origin, previous and family history of PE and history of chronic hypertension. Significant contributions in explaining log(10) uterine artery PI were provided from maternal characteristics but not from the method of conception. The median uterine artery PI multiple of the median (MoM) in the IVF group (1.02 MoM) and in the OI group (1.03 MoM) were not significantly different from that of the spontaneous conception group (1.01 MoM; P= 0.870 and P= 0.296, respectively).

CONCLUSIONS

Conception by IVF substantially increases the risk for early-PE, through a mechanism unrelated to clinically measurable impairment in placental perfusion.

Risk factors and prediction of preeclampsia

Inadequate trophoblast invasion of the spiral arteries in early pregnancy, an increased inflammatory response and changes in the immune answer to paternal antigens are considered aetiological factors in preeclampsia. Searching for factors related to these angiogenic, anti-angiogenic, immunologic and inflammatory mechanisms may provide methods to determine which patient will develop preeclampsia predating the onset of the clinical manifestations of the disease. Screening for preeclampsia in the first trimester has had Limited success. Currently, maternal characteristics, clinical history, maternal serum biochemistry and uterine artery Doppler sonography before 14 weeks are being investigated. Preeclampsia in a previous pregnancy is still the strongest predictor. In the second trimester, uterine artery Doppler has a detection rate around 60% but also a high false positive rate of 25%. First trimester uterine artery Doppler studies have high sensitivity but poor specificity with a high false positive rate. Combination of first trimester uterine artery Doppler with patient characteristics and maternal serum biochemistry, specifically placental protein 13 holds promise but further evaluation is needed. Maternal serum markers including inhibin A, activin A, soluble FMS-Like tyrosine kinase 1, endoglin, pregnancy associated plasma protein A and others, when used alone have proved poor predictors of preeclampsia. Most studies have been performed by a limited group of researchers in a population with a high risk and no validation studies of any method in other populations are available. Results are difficult to compare due to differences in methodology, and differences in the end point studied.There are still no good methods of preventing preeclampsia once a high risk has been determined.

Assisted reproductive technology and placenta-mediated adverse pregnancy outcomes

OBJECTIVE

To estimate whether the use of specific types of assisted reproductive technology (ART) is associated with an increased risk of placenta-mediated pregnancy complications, which include preeclampsia, stillbirth, small for gestational age at birth, and placental abruption.

METHODS

A population-based retrospective cohort study was conducted on singleton pregnancies conceived by different types of ART based on the 2004-2007 Ontario Niday Perinatal Database. Patients with fetal anomalies and maternal health problems were excluded as important confounders. Three exposed groups were created by the subtype of ART, including in vitro fertilization with or without intracytoplasmic sperm injection, intrauterine insemination, and ovulation induction. The nonexposed groups were the singleton pregnancies conceived naturally. For each exposed woman, four women from the nonexposed group were randomly matched by maternal age and parity.

RESULTS

There were 2,118 exposed participants and 8,420 matched nonexposed participants in the study. The sample size provided 80% power for a relative risk of 2.0 of placenta-mediated adverse pregnancy outcomes with ART. After adjustment of potential confounders, including smoking, delivery hospital level, initiating time of prenatal care, average neighborhood income, fetal sex, and previous cesarean delivery, there was no association observed between different types of ART groups and the composite of placenta-mediated pregnancy complications. Intrauterine insemination was associated with a significantly increased risk of preeclampsia (12 [2.67%] odds ratio 2.2, 95% confidence interval 1.04-5.04) compared with the corresponding control group (23 [1.29%]).

CONCLUSION

Assisted reproductive technology is not associated with an increased risk of the composite outcome of placenta-mediated pregnancy complications among singleton pregnancies.

LEVEL OF EVIDENCE

II.

Uterine Artery Doppler and Its Value in Predicting Preeclampsia

Prematurity is the leading cause of fetal morbidity and mortality. One of the most common reasons for women to have preterm delivery is due to a condition called preeclampsia. Early detection of preeclampsia is key to providing the best obstetric care and lessening the chance of maternal or fetal demise. The problem has been finding accurate ways to detect or predict women who will develop preeclampsia so that they can be closely monitored before the actual symptoms occur. Uterine artery Doppler has been shown to predict pregnancy complications such as preeclampsia. Investigators have shown that many women who develop preeclampsia have abnormal Doppler waveforms. Alone, uterine artery Doppler shows promise but is more accurate when combined with maternal factors such as maternal health history and first-trimester pregnancy-associated plasma protein—A values.

Ultrasound of the placenta: a systematic approach. Part II: functional assessment (Doppler)

Doppler velocimetry is the ideal clinical tool to assess placental performance in high-risk pregnancies. It also has value in predicting later complications and outcome in pregnancies which appear uncomplicated. All three circulations (fetal, placental and maternal) may be interrogated by Doppler technology. In the following review, we present basic physics aspects of Doppler and discuss mainly Doppler investigation of the fetal-placental circulation (umbilical artery, intraplacental circulation) as well as the uterine arteries. The assessment of umbilical blood flow provides information on blood perfusion of the fetal-placental unit. The diastolic blood flow velocity component in umbilical artery increases with advancing gestation. In pregnancies complicated by placental dysfunction, there may be a reduction in the number of functional villi and/or small blood vessels with, as a result, increased impedance, reflected, mainly, by a decrease in end-diastolic velocity. When the resistance increases even more, there is no diastolic forward velocity (absent end-diastolic velocity). Further increase in the resistance causes reversed end-diastolic velocity, which is considered a late step in the cascade of events leading to intrauterine fetal demise. Doppler assessment of the umbilical arteries was found to improve outcome of high-risk pregnancies, and reduce hospital admissions. On the contrary, routine Doppler ultrasound in low risk or unselected populations does not seem to confer benefit on mother or newborn. Uterine artery Doppler is a useful test in predicting pregnancies at high risk of developing complications related to uteroplacental insufficiency. It identifies women who may benefit from increased antenatal surveillance or prophylactic therapy. Three-dimensional power Doppler sonography can provide new insights into placental pathophysiology.