The placental transcriptome of the first-trimester placenta is affected by in vitro fertilization and embryo transfer

Upregulation of miR-181a-5p and miR-125b-2-3p in the Maternal Circulation of Fetuses with Rh-Negative Hemolytic Disease of the Fetus and Newborn Could Be Related to Dysfunction of Placental Function

The transplacental transfer of maternal antibodies to the fetus is a critical mechanism for infant protection and perinatal disease. Hemolytic disease of the fetus and newborn (HDFN) is a representative fetal disease caused by transplacental transfer of maternal IgG antibodies. However, it is unclear whether placental-related miRNAs are expressed in Rh-HDFN. Through the investigation of the miR-181a-5p and miR-125b-2-3p levels in maternal plasma using qPCR, we found that both miR-181a-5p and miR-125b-2-3p were highly expressed in maternal plasma of newborns with Rh-HDFN compared with healthy controls, indicating the potential roles of these two miRNAs in Rh-HDFN. To demonstrate whether dysregulation of miR-125b-2-3p and miR-181a-5p contributes to Rh-HDFN development, we analyze the placental miRNA-/mRNA sequencing data (GSE73714) using weighted gene coexpression network analysis (WGCNA), miRNA target predictive databases, and DAVID (Database for Annotation, Visualization, and Integrated Discovery). The results showed that miR-125b-2-3p and miR-181a-5p could regulate several biological processes including cytoplasmic microtubule organization and angiogenesis. Moreover, core promoter sequence-specific DNA binding and protein binding were highly enriched molecular functions, indicating the potential roles of transcriptional regulation. Further pathway enrichment showed that miR-181a-5p and miR-125b-2-3p could regulate several biological pathways that were closely related to placental function, including the FoxO signaling pathway, focal adhesion, mTOR signaling pathway, and central carbon metabolism in cancer. In conclusion, the present results first revealed miRNA expression in the maternal circulation of newborns with Rh-HDFN, which could be caused by dysfunction of the placenta.

The Consequences of Assisted Reproduction Technologies on the Offspring Health Throughout Life: A Placental Contribution

The use of assisted reproductive technologies (ART) worldwide has led to the conception and birth of over eight million babies since being implemented in 1978. ART use is currently on the rise, given growing infertility and the increase in conception age among men and women in industrialized countries. Though obstetric and perinatal outcomes have improved over the years, pregnancies achieved by ART still bear increased risks for the mother and the unborn child. Moreover, given that the first generation of ART offspring is now only reaching their forties, the long-term effects of ART are currently unknown. This is important, as there is a wealth of data showing that life-long health can be predetermined by poor conditions during intrauterine development, including irregularities in the structure and functioning of the placenta. In the current review, we aim to summarize the latest available findings examining the effects of ART on the cardiometabolic, cognitive/neurodevelopmental, and behavioral outcomes in the perinatal period, childhood and adolescence/adulthood; and to examine placental intrinsic factors that may contribute to the developmental outcomes of ART offspring. Altogether, the latest knowledge about life outcomes beyond adolescence for those conceived by ART appears to suggest a better long-term outcome than previously predicted. There are also changes in placenta structure and functional capacity with ART. However, more work in this area is critically required, since the potential consequences of ART may still emerge as the offspring gets older. In addition, knowledge of the placenta may help to foresee and mitigate any adverse outcomes in the offspring.

Obstetric and Perinatal Outcomes After Assisted Reproductive Technology in Women With Cesarean Scar

Introduction

Assisted reproductive technology (ART) and previous Cesarean section (CS) are independently associated with the risk of adverse obstetric and perinatal outcomes in general. Few studies have focused on the association between adverse obstetric and perinatal outcomes and ART used in the high-risk population of women with previous CS.

Materials and Methods

A retrospective cohort study including 14,099 women with a previous delivery and a subsequent delivery between April 2014 and April 2020 was conducted at our hospital. We assessed the risk of adverse obstetric and perinatal outcomes in pregnancies conceived by ART in women with previous CS, using log-binomial regression models.

Results

In women with previous CS, ART singleton pregnancies were associated with an increased risk of maternal complications, such as pregnancy complications, placental anomalies of implantation, postpartum hemorrhage, and preterm birth (PTB), as compared to spontaneously conceived pregnancies. The implementation of ART and previous CS interacted in a synergistic manner to increase the likelihood of the placenta accreta spectrum in women with singleton pregnancies [adjusted relative risk (aRR) 5.30, 95% confidence interval (CI) 4.01–7.00; relative risk due to interaction: 1.41, 95%CI 0.07–2.75]. In women with previous CS who underwent ART, women with singletons conceived through intracytoplasmic sperm injection were at increased risk of velamentous placenta (aRR 2.46, 95%CI 1.35–4.48) compared with those with singletons conceived through in vitro fertilization (IVF), whereas women with singletons conceived through cleavage-stage embryo transfer (ET) were at increased risk of gestational diabetes mellitus (GDM) (aRR 1.74, 95%CI 1.16-2.60) than those with singletons conceived through blastocyst–stage ET.

Conclusion

Pregnancies conceived through ART were at increased risk for adverse obstetric and perinatal outcomes in women who had previously delivered by CS, particularly for placental anomalies of implantation. In women with previous CS undergoing ART, IVF and blastocyst–stage ET may be a relatively safe treatment.

Placental Dysfunction in Assisted Reproductive Pregnancies: Perinatal, Neonatal and Adult Life Outcomes

Obstetric and newborn outcomes of assisted reproductive technology (ART) pregnancies are associated with significative prevalence of maternal and neonatal adverse health conditions, such as cardiovascular and metabolic diseases. These data are interpreted as anomalies in placentation involving a dysregulation of several molecular factors and pathways. It is not clear which extent of the observed placental alterations are the result of ART and which originate from infertility itself. These two aspects probably act synergically for the final obstetric risk. Data show that mechanisms of inappropriate trophoblast invasion and consequent altered vascular remodeling sustain several clinical conditions, leading to obstetric and perinatal risks often found in ART pregnancies, such as preeclampsia, fetal growth restriction and placenta previa or accreta. The roles of factors such as VEGF, GATA3, PIGF, sFLT-1, sEndoglin, EGFL7, melatonin and of ART conditions, such as short or long embryo cultures, trophectoderm biopsy, embryo cryopreservation, and supraphysiologic endometrium preparation, are discussed. Inflammatory local conditions and epigenetic influence on embryos of ART procedures are important research topics since they may have important consequences on obstetric risk. Prevention and treatment of these conditions represent new frontiers for clinicians and biologists involved in ART, and synergic actions with researchers at molecular levels are advocated.

Placental Abnormalities and Placenta-Related Complications Following In-Vitro Fertilization: Based on National Hospitalized Data in China

INTRODUCTION

Emerging evidence has shown that in-vitro fertilization (IVF) is associated with higher risks of certain placental abnormalities or complications, such as placental abruption, preeclampsia, and preterm birth. However, there is a lack of large population-based analysis focusing on placental abnormalities or complications following IVF treatment. This study aimed to estimate the absolute risk of placental abnormalities or complications during IVF-conceived pregnancy.

METHODS

We conducted a retrospective cohort study of 16 535 852 singleton pregnancies with delivery outcomes in China between 2013 and 2018, based on the Hospital Quality Monitoring System databases. Main outcomes included placental abnormalities (placenta previa, placental abruption, placenta accrete, and abnormal morphology of placenta) and placenta-related complications (gestational hypertension, preeclampsia, eclampsia, preterm birth, fetal distress, and fetal growth restriction (FGR)). Poisson regression modeling with restricted cubic splines of exact maternal age was used to estimate the absolute risk in both the IVF and non-IVF groups.

RESULTS

The IVF group (n = 183 059) was more likely than the non-IVF group (n = 16 352 793) to present placenta previa (aRR: 1.87 [1.83-1.91]), placental abruption (aRR: 1.16 [1.11-1.21]), placenta accrete (aRR: 2.00 [1.96-2.04]), abnormal morphology of placenta (aRR: 2.12 [2.07 to 2.16]), gestational hypertension (aRR: 1.55 [1.51-1.59]), preeclampsia (aRR: 1.54 [1.51-1.57]), preterm birth (aRR: 1.48 [1.46-1.51]), fetal distress (aRR: 1.39 [1.37-1.42]), and FGR (aRR: 1.36 [1.30-1.42]), but no significant difference in eclampsia (aRR: 0.91 [0.80-1.04]) was found. The absolute risk of each outcome with increasing maternal age in both the IVF and non-IVF group presented two patterns: an upward curve showing in placenta previa, placenta accreta, abnormal morphology of placenta, and gestational hypertension; and a J-shape curve showing in placental abruption, preeclampsia, eclampsia, preterm birth, fetal distress, and FGR.

CONCLUSION

IVF is an independent risk factor for placental abnormalities and placental-related complications, and the risk is associated with maternal age. Further research is needed to evaluate the long-term placenta-related chronic diseases of IVF patients and their offspring.

Gestational diabetes mellitus in in-vitro fertilization pregnancies - Clinical and placental histological characteristics

INTRODUCTION

We aimed to investigate obstetric and neonatal outcomes and placental histological findings in in vitro fertilization (IVF) pregnancies complicated by gestational diabetes mellitus (GDM) as compared to unassisted pregnancies.

METHODS

This was a retrospective cohort of deliveries at a single university affiliated center between 12/2008 and 01/2020. Included were singleton pregnancies complicated by GDM, for which placental histopathological examination was performed. Obstetric, neonatal and placental outcomes were compared between pregnancies following IVF and unassisted pregnancies. Placental lesions were categorized according to the "Amsterdam" criteria.

RESULTS

Included were 688 deliveries with a diagnosis of GDM with placental examination - 69 IVF pregnancies (IVF group) and 619 unassisted pregnancies (control group). The IVF group was characterized by a significantly higher maternal age and higher rate of nulliparous women - 60.8% vs. 32.9%, p < 0.001. There were no differences in GDM type between the study groups - about two thirds of cases were GDMA1 and on third GDMA2. A higher incidence of preeclampsia was noted in the IVF group - 17.3% vs. 9.3%, p = 0.03, with no difference in cesarean deliveries and birthweight. IVF deliveries were characterized by a significantly higher rate of adverse neonatal outcomes - 18.8% vs. 8.8%, p = 0.008, although this did not attain significance after adjustment to gestational age. No differences were noted in placental histology between the groups.

DISCUSSION

GDM in IVF is associated with a significantly higher rate of adverse neonatal outcomes, as compared with non-assisted pregnancies complicated by GDM. Placental histology does not shed light on these clinical associations.

Placental diseases associated with assisted reproductive technology

The placenta develops from the outer trophoblastic layer following the differentiation of the fertilized ovum and is therefore more susceptible to epigenetic regulatory changes caused by environmental interventions and influences during assisted reproductive technology. Furthermore, the placenta regulates the development of the fetal heart, brain, kidneys, bones, and other tissues and organs [1]. Placental dysplasia leads to poor perinatal outcomes as well as long-term health risks later in life, including neurodevelopmental disorders, tumors, and adult metabolic syndrome [2,3]. In view of the decisive role of the placenta during intrauterine fetal development, Graham J. Burton, an expert in placentology from the University of Cambridge, formally proposed the theory of "placenta-derived chronic diseases" in 2018 based on embryonic-derived diseases [4]. In this review, we summarized the changes in placental morphology and structure, growth dynamics, imprinted and non-imprinted genes, and other aspects attributable to assisted reproduction technology. Our review provides a theoretical basis for further research on placental changes caused by assisted reproductive technology that are most strongly associated with an increased risk of neonatal long-term diseases.

Obstetric and perinatal outcomes of in vitro fertilization and natural pregnancies in the same mother

OBJECTIVE

To compare obstetric and perinatal outcomes between pregnancies conceived using in vitro fertilization (IVF) and natural pregnancies of the same women.

DESIGN

This was a case-control study of deliveries between November 2008 and January 2020 in which each IVF pregnancy was matched to a natural pregnancy of the same woman (1:1 ratio).

SETTING

University hospital.

PATIENT(S)

We included women with consecutive live singleton deliveries (>24 weeks of gestation) at the Edith Wolfson Medical Center. We excluded IVF pregnancies attained using egg donation.

INTERVENTION(S)

In vitro fertilization-attained pregnancies (as compared with natural ones).

MAIN OUTCOME MEASURE(S)

Primary outcome: preterm birth (PTB).

SECONDARY OUTCOMES

small for gestational age (SGA) neonates and pregnancy-induced hypertension (PIH; gestational hypertension or pre-eclampsia).

RESULT(S)

A total of 544 IVF pregnancies were matched to 544 natural pregnancies, each in the same woman. In 292 women (53.7%), the natural pregnancy preceded the IVF pregnancy. Maternal age was significantly higher in IVF deliveries. Gestational age at delivery and the rates of PTB, PIH, instrumental delivery, cesarean delivery, and SGA neonates were comparable between IVF and natural pregnancies. Birth weight was slightly lower in IVF pregnancies. On multivariate analysis, IVF was not independently associated with PTB, SGA, or PIH after adjustment for confounders.

CONCLUSION(S)

When compared in a cohort of the same women, natural and IVF-attained pregnancies did not differ with regard to obstetric and perinatal outcomes.

Complications of the third stage of labor in in vitro fertilization pregnancies: an additional expression of abnormal placentation?

OBJECTIVE

To assess the correlation between in vitro fertilization (IVF) and complications of the third stage of labor.

DESIGN

Retrospective cohort of vaginal deliveries from November 2008 to January 2020. Maternal and obstetric outcomes of singleton deliveries were compared between IVF and non-IVF pregnancies.

SETTING

University hospital.

PATIENT(S)

Women with live singleton vaginal deliveries at >24 weeks of gestation.

INTERVENTION(S)

In vitro fertilization-attained pregnancies (compared with spontaneous ones).

MAIN OUTCOME MEASURE(S)

Complications of the third stage of labor, defined as manual placental removal (either entire removal due to nonseparation or exploration of the uterine cavity due to suspected retained products of conception).

RESULT(S)

Overall, 1,264 IVF pregnancies and 34,166 non-IVF pregnancies were included. Deliveries in the IVF group were characterized by an older maternal age, lower parity, higher rate of diabetes and hypertensive disorders, higher rate of placental abnormalities, earlier gestational age, higher rate of labor induction, chorioamnionitis, and instrumental delivery. Complications of the third stage of labor occurred in 5.9% of IVF deliveries and in 2.8% of controls, and blood transfusion was more prevalent in IVF deliveries. The rate of complications of the third stage were higher in both fresh and frozen transfer cycles as compared with spontaneous pregnancies (5.8%, 8.8%, and 2.8%, respectively), although no difference was noted between fresh and frozen transfers. In vitro fertilization was associated independently with complications of the third stage of labor after adjustment for potential confounders.

CONCLUSION(S)

In vitro fertilization is associated independently with an increased risk of complications of the third stage of labor.

Placental disorders of pregnancy in subsequent IVF pregnancies - a sibling cohort

RESEARCH QUESTION

To assess whether the incidence of placental disorders of pregnancy decreases with increasing parity in repeat IVF pregnancies, in the same way as natural pregnancies.

DESIGN

This was a retrospective cohort of deliveries between November 2008 and January 2020, in a single university-affiliated medical centre. The study included women with only IVF-attained singleton pregnancies (no natural conception) with at least two deliveries, and compared the obstetric and perinatal outcomes between first, second and third deliveries. Each woman served as her own control. The primary outcome was the incidence of placental-related disorders of pregnancy, defined as small for gestational age (SGA) neonates and/or pre-eclampsia.

RESULTS

A total of 307 first deliveries, 307 second deliveries and 49 third deliveries by the same women were compared. A trend for a decreased rate of pre-eclampsia was noted with increased parity (P = 0.06) and a significant decrease in the rate of SGA: 11.7% for first delivery, 7.8% for second delivery and 2.0% for third (P = 0.04). This difference in SGA incidence was maintained in a matched sub-analysis of the 49 women with three deliveries (P = 0.04), and after adjustment for fresh/frozen embryo transfer (P = 0.03). Although SGA and pre-eclampsia were generally more common in IVF than natural pregnancies, their decrease with increasing parity mimicked that in natural pregnancies.

CONCLUSION

IVF pregnancies are associated with an increased risk of placental disorders of pregnancy. However, they exhibit a decrease in incidence with increasing parity.