Background and Aims:
Disruptive behaviour (DBD) and aggression related disorders have been studied from a neurobiological and hormonal perspective. If any contributing effects to psychopathology were found most notably adrenal hormones (DHEA, Cortisol) and gonadal hormones (Testosterone) were mentioned. Less is known about the role of Estradiol in the onset and maintenance of aggression and DBD in both boys and girls.
Methods:
A systematic review was conducted using Ovid Medline, Psycinfo and Embase databases (up to 30 July 2018), using [estradiol] and [aggression] as search terms. Within the search results only studies in humans and minors (age 0-18) were included. 
Results:
In total 9 studies were found in which Estradiol and aggressive behaviour were used as (in)dependent variables. Only one study tested hormone concentrations in a clinical sample of conduct disorder girls. In some studies no association was found between Estradiol concentrations and aggression, in some an association was found only when personality traits or low Cortisol concentrations were equally present. Corrections for menstrual cycle phase were lacking. Another limitation is that not every study corrected for effects of Testosterone as gonadal precursor. 
Conclusions:
Studies on Estradiol and aggressive behaviour or DBD produce mixed results, with some studies showing no associations, some only in boys or girls, or only when a mediating effect of emotional instability or negative life events occurred. 
Future studies should control for effects of Cortisol and Testosterone and use mixed gender samples, preferably after puberty onset as results of Estradiol assays are more reliable when taken after gonadarche.

ESTRADIOL AND AGGRESSIVE BEHAVIOUR IN BOYS AND GIRLS: A SYSTEMATIC REVIEW.