Fetal Biometry: A Method for Comparing Local Curve Populations with Those from Major Reference Standards.

OBJECTIVES: This study aimed to present a statistical method for assessing potential differences between fetal growth standard curves and local curve population. METHODS: This was an observational repeated measures longitudinal study. We used a simulation model to generate random distribution of the international population from the IG-21st for fetal AC using the original equations of means and standard deviations (SD) obtained by the fractional polynomial method. A general linear model (GLM) allowed us to calculate new equations originating from simulated intergrowth-21st data (SIM_IG21st) and to compare them, by visual inspection of the estimated coefficients and their 95% CI, with the original published. We used further GLMs for evaluating the goodness of fitting of our local curve and comparing the relative equations of means and SD with those of SIM_IG21st. Finally, the impact of percentile differences between the 2 curves was quantified. RESULTS: SIM_IG21st data yielded very similar coefficients than those of IG-21st reference to such an extent that means and SD and percentiles of interest were identical to the original. The comparison between SIM_IG21st curve and local curves showed a nonsignificant intercept and a slight difference of the 2 slopes (GA and GA3) for the equations of the mean. As a result, the local curve resulted in greater AC values. A difference in the intercept but not in the slopes (GA2, GA3, and GA3 * lnGA) was instead reported for the equations of the SD. In the percentile comparison, the local curve resulted in an overestimation of the 3rd and the 10th percentile that corresponded to the 4th and 12th percentiles of SIM_IG21st, respectively. CONCLUSION: This statistical method allows sonographers to assess potential differences between standard curves and local curve population, enabling a more proper identification of abnormal growth trajectories.

Maternal Subcutaneous and Visceral Adipose Ultrasound Thickness in Women with Gestational Diabetes Mellitus at 24-28 Weeks' Gestation.

OBJECTIVE: To compare the sonographic measurement of maternal subcutaneous and visceral adipose thickness between pregnant women with gestational diabetes mellitus (GDM) and patients with nondiabetic pregnancies. METHODS: Adipose thickness was measured by transabdominal ultrasound in pregnant women attending our antenatal clinics at 24-28 weeks' gestation. All patients underwent a 75-g oral glucose challenge as a diagnostic test for GDM. RESULTS: The study population comprised 56 women with a positive glucose challenge test and 112 nondiabetic pregnancies. Measurements of subcutaneous and visceral adipose tissues were converted into multiples of the median (MoM), adjusted for gestational age. The mean subcutaneous thickness MoM in patients with GDM was significantly higher compared to nondiabetic pregnancies (1.31 vs. 1.07; p = 0.011). Similarly, the mean visceral thickness MoM was higher in women with a positive oral glucose tolerance test compared to controls (1.61 vs. 1.06; p < 0.001). Multivariate logistic regression analysis demonstrated that visceral adipose thickness, but not subcutaneous thickness, was significantly and independently associated with GDM (odds ratio 34.047, 95% confidence interval 9.489-122.166). CONCLUSIONS: Sonographic thickness of maternal visceral adipose tissue at 24-28 weeks' gestation was higher in women with GDM compared to nondiabetic pregnancies, independently from other known risk factors associated with GDM.

In Estimated Good Prognosis Patients Could Unexpected "Hyporesponse" to Controlled Ovarian Stimulation be Related to Genetic Polymorphisms of FSH Receptor?

It has been reported that 10% to 15% of young normogonadotrophic women show suboptimal response to standard gonadotropin-releasing hormone-a long protocol. These patients require higher doses of exogenous follicle-stimulating hormone (FSH). This phenomenon could be associated with genetic characteristics. In this study, FSH receptor polymorphism was retrospectively evaluated in 42 normoresponder young women undergoing an in vitro fertilization/intracytoplasmic sperm injection cycle; patients were stratified according to recombinant human FSH (r-hFSH) consumption. We selected 17 normoresponder young patients who required a cumulative dose of recombinant FSH (rFSH) >2500 UI (group A). A control group was randomly selected among patients who required a cumulative dose of rFSH <2500 UI (group B). Follicle-stimulating hormone receptor (FSH-R) 307Ala and 680Ser variants were analyzed in all our patients. Our results show that the mean number of rFSH vials (36.3 ± 7.5 vs 28.6 ± 4.5, P = .0001) and days of stimulation (12.7 ± 2.4 vs 10.8 ± 2.8, P = .03) were significantly lower in group B, whereas the number of oocytes retrieved (7.1 ± 1.5 vs 9.6 ± 2.4; P = .0005) and the average number of embryos transferred (2.1 ± 0.7 vs 2.7 ± 0.4; P = .001) were significantly lower in group A. Estradiol serum levels on the human chorionic gonadotrophin day were significantly lower in group A (997.8 ± 384.9 pg/mL vs 1749.1 ± 644.4; P = .0001). The incidence of the Ser/Ser genotype was higher in patients with higher r-hFSH consumption (group A; P = .02). Based on our results, we hypothesize an association between the FSH-R polymorphisms and a "hyporesponse" to exogenous FSH.