Decreased fetal thymus size in pregnancies after assisted reproductive technologies

Figures & data

Figure 1. Fetal thymus transverse diameter measurement method.

Figure 2. Fetal thymic-thoracic ratio measurement method. (A) Thymus diameter (anteroposterior thymus diameter) and (B) thorax diameter (intrathoracic mediastinal diameter), Fetal thymic-thoracic ratio: (A)/(B).

Table 1. Demographic characteristics of the study and control groups.

	Study group (n:58)	Control group (n:146)	p Value
Maternal age (years)	32 (23–43)	30 (19–43)	.088^a
BMI (kg/m^2)	26.55 (23.8–28.9)	26.1 (23–28.4)	.139^a
Gestational age at time of study (weeks)	20.92 (19.42–22.7)	21.14 (19.42–22.84)	.096^a

BMI: body mass index.

^aMann–Whitney U test.

Table 2. Comparison of fetal thymus transverse diameter and fetal thymic-thoracic ratio in the study and control groups.

	Study group (n:58)	Control group (n:146)	p value
Transverse diameter (mm)	16.8 (13.8–19)	20.8 (18.1–23.1)	.001^a
Thymic-thoracic ratio	0.306 (0.258–0.361)	0.432 (0.392–0.46)	.001^a

^aMann–Whitney U test.