ESPE Yearbook of Paediatric Endocrinology

Horm Behav. 2020;126:104849. 10.1016/j.yhbeh.2020.104849. https://www.sciencedirect.com/science/article/abs/pii/S0018506X20301756?via%3Dihub

In brief: This study used functional MRI to compare resting state functional connectivity in women who started oral contraception during puberty or adulthood. It shows that pubertal onset of oral contraception is associated with higher connectivity in specific cortical regions.

Comment: Puberty represents a crucial window of sensitivity regarding the organizing effects of sex steroids on brain development, in particular in females (1). Recent evidence suggests that oral contraception induces structural and functional changes in the adult brain. Women taking oral contraception show region-specific increases and decreases in grey or white matter and functional differences in memory and emotion (2, 3).

This study included 75 women aged 18 to 26 years. Of these, 12 were pubertal/adolescent users of oral contraception who had started within 6 months following menarche, a further 12 were adult users, and the others had never used oral contraception. Women taking oral contraception were tested in the ‘active phase’ of combined ethinyl estradiol and progestin. Functional MRI showed that oral contraception increased connectivity in the frontal regions. Pubertal onset of oral contraception was associated with higher connectivity in the salience network (bilateral insula, anterior cingulate cortex, mid-cingulate cortex, superior temporal gyrus, and parts of the dorsolateral prefrontal cortex). These results suggest that the use of exogenous sex steroids may alter the physiological neuronal reorganization and pruning that takes place during puberty. This raises question regarding the potential effects of early oral contraception on mental health in adolescent and later in life.

Reference: 1. Bakker J. (2019) The Sexual Differentiation of the Human Brain: Role of Sex Hormones Versus Sex Chromosomes. Curr Top Behav Neurosci.43:45-67.2. Pletzer, B. (2019) Sex hormones and gender role relate to grey matter volumes in sexually dimorphic brain areas. Front. Neurosci. 13, 592.3. Sharma R, Smith SA, Boukina N, Dordari A, Mistry A, Taylor BC, Felix N, Cameron A, Fang Z, Smith A, Ismail N. (2020) Use of the birth control pill affects stress reactivity and brain structure and function. Hormones and Behavior 124, 104783.