Second trimester prediction of gestational diabetes: maternal analytes as an additional screening tool

First trimester maternal serum PAPP-A and free β-hCG levels and risk of SGA or LGA in women with and without GDM

BACKGROUND

Maternal gestational diabetes (GDM), small (SGA) and large (LGA) for gestational age neonates are associated with increased morbidity in both mother and child. We studied how different levels of first trimester pregnancy associated plasma protein-A (PAPP-A) and free beta human chorionic gonadotropin (fβ-hCG) were associated with SGA and LGA in GDM pregnancies and controls.

METHODS

Altogether 23 482 women with singleton pregnancies participated in first trimester combined screening and delivered between 2014 and 2018 in Northern Finland and were included in this retrospective case-control study. Women with GDM (n = 4697) and controls without GDM (n = 18 492) were divided into groups below 5th and 10th or above 90th and 95th percentile (pc) PAPP-A and fβ-hCG MoM levels. SGA was defined as a birthweight more than two standard deviations (SD) below and LGA more than two SDs above the sex-specific and gestational age-specific reference mean. Odds ratios were adjusted (aOR) for maternal age, BMI, ethnicity, IVF/ICSI, parity and smoking.

RESULTS

In pregnancies with GDM the proportion of SGA was 2.6% and LGA 4.5%, compared to 3.3% (p = 0.011) and 1.8% (p < 0.001) in the control group, respectively. In ≤ 5th and ≤ 10th pc PAPP-A groups, aORs for SGA were 2.7 (95% CI 1.5-4.7) and 2.2 (95% CI 1.4-3.5) in the GDM group and 3.8 (95% CI 3.0-4.9) and 2.8 (95% CI 2.3-3.5) in the reference group, respectively. When considering LGA, there was no difference in aORs in any high PAPP-A groups. In the low ≤ 5 percentile fβ-hCG MoM group, aORs for SGA was 2.3 (95% CI 1.8-3.1) in the control group. In fβ-hCG groups with GDM there was no association with SGA and the only significant difference was ≥ 90 percentile group, aOR 1.6 (95% CI 1.1-2.5) for LGA.

CONCLUSION

Association with low PAPP-A and SGA seems to be present despite GDM status. High PAPP-A levels are not associated with increased LGA risk in women with or without GDM. Low fβ-hCG levels are associated with SGA only in non-GDM pregnancies.

Establishment and validation of a sensitive LC-MS/MS method for quantification of urinary estrogens in women with gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is not only a threat to the health of pregnant women, but also has profound effects on the health of offspring. Studies have shown that the imbalance of estrogen metabolism is associated with an increased risk of GDM. In this study, an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established and validated for simultaneous quantification of thirteen estrogens in the urine of GDM women, including estrone (E1), estradiol (E2), estriol (E3), and their hydroxylated and methylated metabolites. The method was achieved on a Waters CORTECS C18 column (2.1 mm × 150 mm, 1.6 µm) within 8.5 min. The linear range of thirteen estrogens in urine was 2-1000 pg·mL^-1. Both intra- and inter-day precision for each analyte were less than 15%, with accuracies ranging from 8.3% to 7.3%. The extraction recoveries rate were between 86% and 111%, and stability verification results met the requirements for determination of biological samples. The results suggested that the concentrations of estrogens in all urine samples range from 0.08 to 134.06 (pg·mg^-1 creatinine). The mean levels of E1, E2 and most estrogen metabolites in the urine of GDM women were higher than those in healthy pregnant women. Notably, the mean level of 2-hydroxyestrone (2-OHE1) in GDM women was 13.2-fold lower than that in healthy pregnant women. The types of estrogens with the highest mean levels in the urine of GDM and healthy pregnant women were obviously different, which are 2-methoxyestrone (2MeOE1) and E3, respectively. Our results demonstrated that this specific and sensitive method is suitable for quantifying estrogens in human urine and could provide support for further research on estrogen-related pathological mechanisms in GDM and other diseases.