Correlation of first-trimester fetal crown-rump length with outcome of pregnancy and birth weight

Embryonic size and growth and adverse birth outcomes: the Rotterdam Periconception Cohort

STUDY QUESTION

Is early embryonic size and growth in the first trimester of pregnancy associated with adverse birth outcomes?

SUMMARY ANSWER

Larger embryonic crown-rump length (CRL) and embryonic volume (EV) are associated with lower odds of adverse birth outcomes, especially small for gestational age (SGA).

WHAT IS ALREADY KNOWN

Preterm birth, SGA, and congenital anomalies are the most prevalent adverse birth outcomes with lifelong health consequences as well as high medical and societal costs. In the late first and second trimesters of pregnancy, fetuses at risk for adverse birth outcomes can be identified using 2-dimensional ultrasonography (US).

STUDY DESIGN, SIZE, DURATION

Between 2009 and 2018, singleton pregnancies were enrolled in this ongoing prospective Rotterdam Periconception Cohort.

PARTICIPANTS/MATERIALS, SETTING, METHODS

This study included 918 pregnant women from a tertiary hospital in the Netherlands. Pregnancy dating was based on either a regular menstrual cycle (for natural pregnancies) or a conception date (for ART pregnancies). CRL and EV were measured using Virtual Reality software on 3-dimensional (3D) ultrasound scans, repeatedly performed around 7, 9, and 11 weeks of gestation. The main outcome measure was adverse birth outcome, defined as the composite of SGA (birth weight <10th percentile), preterm birth (<37th week of gestation), congenital anomalies (Eurocat criteria), stillbirth (>16th week of pregnancy), or early neonatal mortality (≤7 days of life). Reference curves for CRL and EV were constructed. Cross-sectional (CRL/EV <20th percentile at 7, 9, and 11 weeks of gestation) and longitudinal (CRL/EV growth trajectories between 6th and 13th weeks) regression analyses were performed, with adjustments for the participants' educational level, smoking, parity, age, BMI, geographical background, mode of conception, and fetal sex.

MAIN RESULTS AND THE ROLE OF CHANCE

Of the 918 pregnant women included, the median age was 32.3 years, and 404 (44%) pregnancies had been conceived via ART. In 199 (22%) pregnancies, there was an adverse birth outcome. Regression analyses showed that at 7 weeks of gestation onwards, embryos with a CRL <20th percentile had an ∼2-fold increased odds of adverse birth outcome (adjusted odds ratio (aOR) 2.03, 95% CI 1.21-3.39, P = 0.007). Similar associations were found for EV <20th percentile but were not statistically significant. These findings were mainly driven by the strong association between embryonic size and SGA (e.g. 7-week CRL: aOR 2.18 (1.16-4.09), P = 0.02; 9-week EV: aOR 2.09 (1.10-3.97, P = 0.02). Longitudinal growth trajectories of CRL, but not of EV, were associated with adverse birth outcomes. Both CRL and EV growth trajectories were associated with SGA.

LIMITATIONS, REASONS FOR CAUTION

The tertiary hospital population and the availability of sophisticated 3D-ultrasound techniques limit the generalizability of this study to general populations and settings.

WIDER IMPLICATIONS OF THE FINDINGS

Already very early in the first trimester of pregnancy, embryos with increased risks of an adverse birth outcome can be identified by using 3D-US and Virtual Reality. This expands the window of opportunity to enable the development of future interventions to potentially improve pregnancy outcomes and offspring health during their life-course.

STUDY FUNDING/COMPETING INTEREST(S)

This work was funded by the Department of Obstetrics and Gynecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands. The authors declare no conflicts of interest.

TRIAL REGISTRATION NUMBER

NL4115.

Assessing the predictive value of first trimester ultrasound and biochemical markers in miscarriage: A scoping review

INTRODUCTION

Vaginal bleeding in the first trimester of pregnancy generates anxiety and uncertainty for expecting parents. The ability to determine pregnancy outcome through a first trimester ultrasound scan remains a challenge in obstetrics. Several first trimester ultrasound markers used individually or in combination, as well as ultrasound markers used in combination with biochemical markers, have been studied to determine their predictive value in pregnancy outcome. This scoping review was performed to determine which markers have already been investigated for this purpose.

METHODS

An extensive and systematic database search was performed using four different categories of keywords which were combined using Boolean terms. A total of 14 variables were included on the final data charting forms. Data was synthesised collectively for each variable and then separately for the studies analysing only one marker. For the studies which analysed multiple markers, data was synthesised based on the number of markers per study.

RESULTS

The search yielded 3608 studies, of which 128 were ultimately used for this review. Data extraction, based on predetermined eligibility criteria, was performed by two authors independently. Seventy-seven (62.6%) studies investigated the predictive value of a single ultrasound marker. The remaining 46 (37.4%) studies explored multiple markers, of which at least one was an ultrasound marker.

CONCLUSION

This review identified several discrepancies among different studies. This highlights the need for better consensus among researchers to allow for the design of a predictive model which enables extrapolation of findings to all pregnant women.

IMPLICATIONS FOR PRACTICE

Through the study of ultrasound and biochemical markers in the first trimester of pregnancy, clinicians may provide a more accurate prediction of pregnancy outcome following threatened miscarriage.

The correlation between birth weight and insulin-like growth factor-binding protein-1 (IGFBP-1), kisspeptin-1 (KISS-1), and three-dimensional fetal volume

PURPOSE

This study aimed to determine the relationship between birth weight, and maternal serum insulin-like growth factor-binding protein-1 (IGFBP-1) and kisspeptin-1 (KISS-1) levels, and first-trimester fetal volume (FV) based on three-dimensional ultrasonography.

MATERIALS AND METHODS

The study included 142 pregnant women at gestational week 11°-13⁶. All fetuses were imaged ultrasonographically by the same physician. Maternal blood samples were collected at the time of ultrasonographic evaluation and analyzed for IGFBP-1 and KISS-1 levels via enzyme-linked immunosorbent assay (ELISA). Maternal and neonatal weights were recorded at birth. Birth weight ≤10th and the >90th percentiles was defined as small and large for gestational age (SGA and LGA), respectively.

RESULTS

Median crown-rump length (CRL), FV, and maternal serum IGFBP-1 and KISS-1 levels were 58.2 mm (35.3-79.2 mm), 16.3 cm³ (3.8-34.4 cm³), 68.1 ng mL^-1 (3.8-377.9 mL^-1), and 99.7 ng L^-1 (42.1-965.3 ng L^-1), respectively. First-trimester IGFBP-1 levels were significantly lower in the mothers with LGA neonates (p < .05). There was a significant positive correlation between CRL and FV, and between the IGFBP-1 and KISS-1 levels. IGFBP-1 levels and maternal weight at delivery were negatively correlated with neonatal birth weight. There was no correlation between CRL or FV and maternal IGFBP-1 or KISS1 levels (p > .05). The maternal IGFBP-1 level during the first trimester was a significant independent factor for SGA and LGA neonates (Odds ratio (OR): 0.011, 95%CI: 1.005-1.018, p < .001; and OR: 1.297, 95%CI: 1.074-1.566, p = .007, respectively). There was no significant relationship between SGA or LGA, and CRL, FV, or the KISS-1 level.

CONCLUSIONS

As compared to the maternal KISS-1 level, the maternal IGFBP-1 level during the first trimester might be a better biomarker of fetal growth. Additional larger scale studies are needed to further delineate the utility of IGFBP-1 as a marker of abnormal birth weight.

First-Trimester Crown-Rump Length and Embryonic Volume of Fetuses with Structural Congenital Abnormalities Measured in Virtual Reality: An Observational Study

Background. With the introduction of three-dimensional (3D) ultrasound it has become possible to measure volumes. The relative increase in embryonic volume (EV) is much larger than that of the crown-rump length (CRL) over the same time period. We examined whether EV is a better parameter to determine growth restriction in fetuses with structural congenital abnormalities. Study Design, Subjects, and Outcome Measures. CRL and EV were measured using a Virtual Reality (VR) system in prospectively collected 3D ultrasound volumes of 56 fetuses diagnosed with structural congenital abnormalities in the first trimester of pregnancy (gestational age 7⁺⁵ to 14⁺⁵ weeks). Measured CRL and EV were converted to z-scores and to percentages of the expected mean using previously published reference curves of euploid fetuses. The one-sample t-test was performed to test significance. Results. The EV was smaller than expected for GA in fetuses with structural congenital abnormalities (−35%  p < 0.001, z-score −1.44  p < 0.001), whereas CRL was not (−6.43%  p = 0.118, z-score −0.43  p = 0.605). Conclusions. CRL is a less reliable parameter to determine growth restriction in fetuses with structural congenital abnormalities as compared with EV. By measuring EV, growth restriction in first-trimester fetuses with structural congenital abnormalities becomes more evident and enables an earlier detection of these cases.