Background

Pituitary gland height reflects secretory activity of the hypothalamo-pituitary axis.

Objective

To assess the cumulative impact of fetal growth and sex on pituitary gland height in premature twins, dissociated from prematurity.

Materials and Methods

A retrospective study was conducted, assessing the pituitary gland height in 63 pairs of preterm twins, measured from T1-weighted magnetic resonance imaging (MRI). Auxological parameters, including body weight, body length, and head circumference, at birth and at the time of MRI, were used as proxies for fetal and postnatal growth, respectively. The study population was divided into two groups, using corrected age at around term equivalent as the cutoff point. Statistical analysis was performed using mixed-effects linear regression models.

Results

When pituitary gland height was evaluated at around term equivalent, a greater pituitary gland height, suggesting a more immature hypothamo-pituitary axis, was associated with the twin exhibiting lower auxological data at birth. The same association was observed when body weight and length at MRI were used as covariants. In the group evaluated after term equivalent, a smaller pituitary gland height, suggesting a more mature hypothamo-pituitary axis, was associated with male sex. This difference was observed in twin pairs with higher average body weight at birth, and in babies exhibiting higher auxological data at MRI.

Conclusion

After isolating the effect of prematurity, at around term equivalent, pituitary gland height reflects the cumulative impact of fetal growth on the hypothalamo-pituitary axis. Subsequently, pituitary gland height shows effects of sex and of fetal and postnatal growth.

Graphical Abstract

中文翻译：

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通过磁共振成像评估早产双胞胎的垂体高度：生长和性别的影响

背景

垂体高度反映了下丘脑-垂体轴的分泌活动。

客观的

评估胎儿生长和性别对早产双胞胎脑垂体高度的累积影响（与早产无关）。

材料和方法

进行了一项回顾性研究，评估了 63 对早产双胞胎的垂体高度，通过 T1 加权磁共振成像 (MRI) 进行测量。生长学参数，包括出生时和 MRI 时的体重、体长和头围，分别用作胎儿和出生后生长的指标。研究人群被分为两组，使用足月左右的校正年龄作为分界点。使用混合效应线性回归模型进行统计分析。

结果

当以足月当量评估垂体高度时，垂体高度较高，表明下丘脑-垂体轴更不成熟，与出生时表现出较低生长学数据的双胞胎相关。当体重和 MRI 的身长用作协变量时，观察到相同的关联。在足月后评估的组中，垂体高度较小，表明下丘脑-垂体轴更成熟，与男性相关。这种差异在出生时平均体重较高的双胞胎中以及在 MRI 中表现出较高生长学数据的婴儿中观察到。

结论

在分离出早产的影响后，在足月当量时，垂体高度反映了胎儿生长对下丘脑-垂体轴的累积影响。随后，垂体高度显示出性别以及胎儿和出生后生长的影响。

图形概要