Assisted Reproductive Technology Surveillance - United States, 2016

Maternal C-reactive protein and in vitro fertilization (IVF) cycles

Embryo implantation is accompanied by a potent inflammatory response, and a gradient of cytokines and chemokines produced by endometrial cells supports the embryo-endometrial interaction. C-reactive protein (CRP) serves as an early marker of inflammation and recent studies have illustrated that controlled ovarian hyperstimulation (COH) could increase its levels. Interestingly, a high chance of pregnancy has been reported in women who had an elevated CRP level on the day of embryo transfer. It seems an elevated systemic inflammation in the in vitro fertilization (IVF) cycle can increase the implantation and pregnancy rates. However, the results regarding the association of CRP with ART outcomes are controversial. Therefore, in this review, we aimed to describe how CRP levels change during a cycle of IVF treatment and which factors can potentially affect this pattern of change. Furthermore, the association of CRP with ART outcomes has been discussed.

Timing of exposure to gonadotropins has differential effects on the conceptus: evidence from a mouse model†

Superovulation with gonadotropins alters the hormonal milieu during early embryo development and placentation, and may be responsible for fetal and placental changes observed after in vitro fertilization (IVF). We hypothesized that superovulation has differential effects depending on timing of exposure. To test our hypothesis, we isolated the effect of superovulation on pre- and peri-implantation mouse embryos. Blastocysts were obtained from either natural mating or following superovulation and mating, and were transferred into naturally mated or superovulated pseudopregnant recipient mice. Fetal weight was significantly lower after peri-implantation exposure to superovulation, regardless of preimplantation exposure (p = 0.006). Placentas derived from blastocysts exposed to superovulation pre- and peri-implantation were larger than placentas derived from natural blastocysts that are transferred into a natural or superovulated environment (p < 0.05). Fetal-to-placental weight ratio decreased following superovulation during the pre- or peri-implantation period (p = 0.05, 0.01, respectively) and these effects were additive. Peg3 DNA methylation levels were decreased in placentas derived from exposure to superovulation both pre- and peri-implantation compared with unexposed embryos and exposure of the preimplantation embryo only. Through RNA sequencing on placental tissue, changes were identified in genes involved in immune system regulation, specifically interferon signaling, which has been previously implicated in implantation and maintenance of early pregnancy in mice. Overall, we found that the timing of exposure to gonadotropin stimulation can have differential effects on fetal and placental growth. These findings could impact clinical practice and underscores the importance of dissecting the role of procedures utilized during IVF on pregnancy complications.

Which key performance indicators are optimal to assess clinical management of assisted reproduction cycles?

Like all industries, fertility clinics should identify and follow reference markers of its activity-key performance indicators (KPI)-to allow assisted reproductive technology outcomes to be monitored and compared. Clinical KPIs revolve around following set parameters of the patient population, procedures, and outcome data. Moreover, KPIs should also include identified protocols and standard operating procedures followed in daily practice and should keep track of multiple pregnancy rates, a ruthless confounder of assisted reproductive technology outcomes.

Perinatal outcome in children born after assisted reproductive technologies

Over the past 40 years access and effectiveness of assisted reproductive technologies (ART) have increased, and to date more than 8 million children have been conceived after ART globally. Most pregnancies resulting from ART are uncomplicated and result in the birth of healthy children. Yet, it is well known that pregnancies following ART are more likely to be affected by obstetric complications such as hypertensive disorders in pregnancy, preterm birth, and low birth weight compared with spontaneously conceived pregnancies. ART children are also at increased risk of birth defects. The majority of the problems arise as a result of multiple pregnancies and can be reduced by transferring a single embryo, thereby avoiding multiple pregnancies. New ART technologies are constantly introduced, and monitoring of the health of ART children is crucial.

Advancements in the gold standard: Measuring steroid sex hormones by mass spectrometry

Sex hormones, such as testosterone and estrogens, play an essential role in regulating physiological and reproductive development throughout the lifetime of the individual. Although variation in levels of these hormones are observed throughout the distinct stages in life, significant deviations from reference ranges can result in detrimental effects to the individual. Alterations, by either an increase or decrease, in hormone levels are associated with physiological changes, decreased reproductive capabilities, and increased risk for diseases. Hormone therapies (HTs) and assisted reproductive technologies (ARTs) are commonly used to address these factors. In addition to these treatments, gender-affirming therapies, an iteration of HTs, are also a prominent treatment for transgender individuals. Considering that the effectiveness of these treatments relies on achieving therapeutic hormone levels, monitoring of hormones has served as a way of assessing therapeutic efficay. The need for reliable methods to achieve this task has led to great advancements in methods for evaluating hormone concentrations in biological matrices. Although immunoassays are the more widely used method, mass spectrometry (MS)-based methods have proven to be more sensitive, specific, and reliable. Advances in MS technology and its applications for therapeutic hormone monitoring have been significant, hence integration of these methods in the clinical setting is desired. Here, we provide a general overview of HT and ART, and the immunoassay and MS-based methods currently utilized for monitoring sex hormones. Additionally, we highlight recent advances in MS-based methods and discuss future applications and considerations for MS-based hormone assays.

Maternal and perinatal outcomes in programmed versus natural vitrified-warmed blastocyst transfer cycles

RESEARCH QUESTION

Do maternal and perinatal outcomes differ between natural and programmed frozen embryo transfer (FET) cycles?

DESIGN

Retrospective cohort study at a university-affiliated fertility centre including 775 patients who underwent programmed or natural FET cycles resulting in a singleton live birth using blastocysts vitrified between 2013 and 2018.

RESULTS

A total of 384 natural and 391 programmed FET singleton pregnancies were analysed. Programmed FET resulted in higher overall maternal complications (32.2% [126/391] versus 18.8% [72/384]; P < 0.01), including higher probability of hypertensive disorders of pregnancy (HDP) (15.3% [60/391] versus 6.3% [24/384]; P < 0.01), preterm premature rupture of membranes (2.6% [10/391] versus 0.3% [1/384]; P = 0.02) and caesarean delivery (53.2% [206/387] versus 42.8% [163/381]; P = 0.03) compared with natural FET. After controlling for potential confounders, including age, body mass index, parity, smoking status, history of diabetes or chronic hypertension, infertility diagnosis, number of embryos transferred and use of preimplantation genetic testing, the adjusted odds ratio for HDP was 2.39 (95% CI 1.37 to 4.17) and for overall maternal complications was 2.21 (95% CI 1.51 to 3.22) comparing programmed with natural FET groups. The groups did not significantly differ for any perinatal outcomes analysed, including birth weight (3357.9 ± 671.6 g versus 3318.4 ± 616.2 g; P = 0.40) or rate of birth defects (1.5% [6/391] versus 2.1% [8/384]; P = 0.57), respectively.

CONCLUSION

Vitrified-warmed blastocyst transfer in a programmed cycle resulted in a twofold higher probability of HDP compared with transfer in a natural cycle. Natural FET cycle should, therefore, be recommended as first line for all eligible patients undergoing FET to reduce the risk of HDP.

Embryo Biopsy Can Offer More Information Than Just Ploidy Status

As a byproduct of increasing infertility cases, the use of medically assisted reproduction (MAR) has increased. As such, the need to gain information regarding the implantation potential of specific MAR preimplantation embryos prior to transfer has become increasingly critical. One potential source of this information is contained in the blastocoel fluid from day 5/6 embryos. This fluid contains cell-free DNA, proteins, RNA, metabolites, exosomes, etc., and analysis of these contents provides clinicians with an opportunity to gain more data regarding potential of each embryo. While application of preimplantation genetic testing for aneuploidies (PGT-A) may be limited to women of advanced maternal age or with recurrent pregnancy loss, the fluid taken at the time of embryo biopsy can be analyzed for any frozen embryo as well as PGT-A embryos. In both cases, blastocoel fluid analysis provides information regarding a preimplantation embryo's potential for implantation. Moreover, as remnants of apoptosis, embryonic cell-free DNA (cfDNA) and mRNA may lead clinicians to better understand and predict the extent of self-correction occurring within the preimplantation embryo. While analysis of blastocoel components are not yet viable replacements for PGT-A, their study may still reveal critical clinical information about the implantation potential for any given embryo.

Association between the number of top-quality blastocysts and live births after single blastocyst transfer in the first fresh or vitrified-warmed IVF/ICSI cycle

RESEARCH QUESTION

Is there an association between the total number of top-quality blastocysts (TQB) developed in the first IVF/intracytoplasmic sperm injection cycle (ICSI) and live births after a single blastocyst transfer (SBT)?

DESIGN

Pregnancy outcomes from 1336 infertile women who had undergone their first IVF/ICSI treatment and accepted a first-time embryo transfer with a single fresh or vitrified-warmed blastocyst between January 2016 and August 2018 were assessed retrospectively. The restricted cubic splines method was used to evaluate the association between the number of TQB, and ongoing pregnancies and live births.

RESULTS

A significant non-linear functional form was found between the number of TQB and the ongoing pregnancies and live births (P < 0.05). The odds of an ongoing pregnancy or live birth were similar, at about 11% or higher for each additional TQB up to five TQB (odds ratio [OR] 1.11; 95% confidence interval [CI] 1.01-1.21). After this, pregnancy outcomes nearly plateaued, indicating that the number of TQB was not related to pregnancy when it was greater than five.

CONCLUSIONS

The quantity of TQB available for transfer or cryopreservation can provide important predictors for pregnancy and live birth after the first embryo transfer cycle with a single blastocyst. This valuable information may assist with the future application of SBT.

THE GORDON WILSON LECTURE: THE ETHICS OF HUMAN GENOME EDITING

Human genome editing has undergone major technological advances, raising the possibility of treating or preventing many illnesses. Somatic (nonheritable) genome editing, both in vitro and in vivo, is already being employed under a robust regulatory and ethical framework developed for human gene therapy. In contrast, the prospect of germline (heritable) genome editing is much more contentious, and there is currently no consensus on the proper path forward. The 2017 National Academy of Sciences (NAS) and National Academy of Medicine (NAM) report proposed a series of requirements designed to minimize ethical objections while allowing couples to accept the risks of genome editing in order to have a biologically related child without passing on a known genetic disorder. It is vital to prevent gene editing from resulting in unintended negative consequences for individuals with genetic variants. The utilization of genome editing to enhance human function is highly contentious; it may be better to focus on whether an edit creates an "unfair advantage" rather than an enhancement.

Assisted reproductive technology use in the United States: a population assessment

OBJECTIVE

To study social and demographic differentiation of assisted reproduction technology (ART) use at the population level in the United States.

DESIGN

Population-based study.

SETTING

Not applicable.

PATIENT(S)

Women 15-49 years old in the American Community Survey and National Vital Statistics Birth Certificate data from 2010-2017.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE(S)

Birth rate after ART by major sociodemographic categories and likelihood of having an ART birth.

RESULT(S)

Net of education, age, period, and marital status, the incidence rates of ART births are lower for black women (0.57 times; 95% CI, 0.52-0.62) and Hispanic women (0.67 times; 95% CI, 0.57-0.62) relative to white women's rates; for Asian women, the incidence rates are 1.21 times that of white women's rates. Further, the incidence rates of ART births are higher for women with more than a 4-year degree (2.08 times; 95% CI, 1.90-2.27) relative to women with a 4-year degree, and are lower for women with less education. Women who are married have an incidence rate of ART that is 5.72 times (95% CI, 5.37-6.09) that of unmarried women. The incidence rates for 2013-2016 are statistically significantly higher than for 2010 by a factor of 1.16 (95% CI, 1.02-1.31), 1.16 (95% CI, 1.03-1.31), 1.27 (95% CI, 1.12-1.43), and 1.51 (95% CI, 1.43-1.82), respectively. The educational differences in ART exist across all age groups from 20 to 49, but are the largest among the 35-39 and 40-44 age groups.

CONCLUSION(S)

Large differences in the risk of an ART birth and the proportion of births and the total fertility rate due to ART exist across period, age, race, education, and marital status groups in the United States. Current measures of ART births may disguise an unmet need for ART.

Updates on an At-Risk Population: Late-Preterm and Early-Term Infants

The American Academy of Pediatrics published a clinical report on late-preterm (LPT) infants in 2007 that was largely based on a summary of a 2005 workshop convened by the Eunice Kennedy Shriver National Institute of Child Health and Human Development, at which a change in terminology from "near term" to "late preterm" was proposed. This paradigm-shifting recommendation had a remarkable impact: federal agencies (the Centers for Disease Control and Prevention), professional societies (the American Academy of Pediatrics and American College of Obstetricians and Gynecologists), and organizations (March of Dimes) initiated nationwide monitoring and educational plans that had a significant effect on decreasing the rates of iatrogenic LPT deliveries. However, there is now an evolving concern. After nearly a decade of steady decreases in the LPT birth rate that largely contributed to the decline in total US preterm birth rates, the birth rate in LPT infants has been inching upward since 2015. In addition, evidence revealed by strong population health research demonstrates that being born as an early-term infant poses a significant risk to an infant's survival, growth, and development. In this report, we summarize the initial progress and discuss the potential reasons for the current trends in LPT and early-term birth rates and propose research recommendations.

Methylation-reprogrammed AGTR1 results in increased vasoconstriction by angiotensin II in human umbilical cord vessel following in vitro fertilization-embryo transfer

AIMS

Assisted reproductive technologies (ART) have been widely used to treat infertility, which may impact on fetuses and offspring. This study investigated the effects of in vitro fertilization-embryo transfer (IVF-ET) on angiotensin II (AII)-mediated vasoconstrictions in umbilical cord vein, and explored possible reprogrammed methylation mechanism.

MATERIALS AND METHODS

Human umbilical cords were randomly divided into ordinary pregnancy and IVF-ET pregnancy. Vascular studies with AII as well as its specific receptor antagonists losartan and PD123,319 were conducted. Real-time quantitative PCR, Western blotting, and methylation analysis by bisulfite sequencing were performed with the cord vessel samples.

KEY FINDINGS

In IVF-ET group, the maximal response to AII in umbilical vessels was significantly greater than that in the ordinary pregnancy. Using losartan and PD123,319, angiotensin receptor subtype 1 (AT1R) was found mainly responsible for the enhanced contraction in the umbilical vein of IVF-ET pregnancy. Decreased mRNA expression of DNMT3A was found in umbilical vein of IVF-ET group. Hypomethylation of the AGTR1 gene (gene encoding AT1R) in the umbilical veins of the IVF group was found. The data suggested that the IVF-ET treatments altered AII-mediated vasoconstrictions in umbilical veins, which could be partially attributed to the increased expression of AT1R.

SIGNIFICANCE

The hypo-methylation of the AGTR1 gene caused by IVF-ET might play important roles in altered vasoconstrictions, impacting on cardiovascular systems in the long run.