Correlation of nuchal translucency and thyroxine at 11-13 weeks of gestation

Nuchal Translucency and Congenital Heart Defects

Nuchal translucency comprises a temporary accumulation of fluid in the subcutaneous tissue on the back of a fetus's neck, which accompanies the crown-rump length and is observed through an ultrasound performed between 11 and 13 weeks + 6 days gestation. Nuchal translucency is considered to be above normal when values are higher than the 95th/99th percentile or equal to or higher than 2.5/3.5 mm. The first connection between increased nuchal translucency and the presence of congenital heart defects is described in the study of Hyett et al., who observed that they are directly proportional. Since that time, several studies have been conducted to understand if nuchal translucency measurements can be used for congenital heart defect screening in euploid fetuses. However, there is great variability in the estimated nuchal translucency cutoff values for congenital heart defect detection. The purpose of this review was to understand how increased nuchal translucency values and congenital heart defects are related and to identify which of these defects are more frequently associated with an increase in these values.

The Levels of Pregnancy-Associated Plasma Protein (PAPP-A) and Chorionic Gonadotropin (β-hCG) in the Blood Serum of Women with Hypothyroidism in the 1st Trimester of Pregnancy

Introduction

Hypothyroidism occurs in pregnant women at a rate of 0.3% to 3%. The deficiency of thyroid hormones during pregnancy can lead to an increased risk of pregnancy complications and poor health of the child, particularly affecting its psychomotor development due to the intensive growth of the nervous system during gestation. The study attempted to establish the median concentrations of pregnancy-associated plasma protein PAPP-A and the free subunit of human chorionic gonadotropin β-hCG in women with hypothyroidism in the 1st trimester of pregnancy.

Objective

The study attempted to establish the median concentrations of pregnancy-associated plasma protein PAPP-A and the free subunit of human chorionic gonadotropin β-hCG in women with hypothyroidism in the 1st trimester of pregnancy.

Patients and methods

The study included 210 pregnant women between 11 and 13.6 weeks of pregnancy; 105 women were diagnosed with hypothyroidism before or during pregnancy, and 105 women of a similar body weight and gestational age had normal thyroid function.The measurements of the pregnancy parameters studied were performed using the DELFIA^® Xpress system.

Results

Differences in the multiples of the median of the PAPP-A and β-hCG levels between women with hypothyroidism and healthy women were observed.

Conclusion

Introducing correction for patients with hypothyroidism during non-invasive biochemical prenatal testing may allow obtaining more reliable results that would be the basis for referral to invasive procedures.