Why do women get interrupted more than men?

Yes, it's true.  While the term "manterruption" has sprung up to describe the phenomenon, the fact is that women get interrupted just as often by other women as they do by men.  There are several studies that show this, but none adequately explains why this happens.  Some possibilities that have been mentioned in articles and studies:

1. The way we're wired...
1. Men converse competitively, whereas women converse collaboratively.
2. Women have lower self-esteem than men.
2. The way our institutions are structured...
1. With fewer women than men in leadership positions, the power structure favors men over women.
3. Cultural perceptions...
1. People do not interrupt leaders, and men are perceived to be better leaders than women.
2. Women are less supportive of women speakers if they are in a mostly-male audience.
3. Men who break conversational rules are "assertive," while women are "bitchy."

It's possible -- maybe even probable -- that this phenomenon is created by a group of causes.  Also, knowing the exact cause may not be necessary to solving the problem.  The solution could be as simple as conversational self-awareness and even-handed respect.

Further reading...

Hancock, Adrienne B. and Rubin, Benjamin A., Department of Speech and Hearing Services, The George Washington University, Influence of Communication Partner's Gender on Language, Journal of Language and Social Psychology, , 2014 (accessed via the Texas A&M Medical Sciences Library):  https://advance.tamu.edu/wp-content/uploads/2016/01/Journal-of-Language-and-Social-Psychology-2014-Hancock-0261927X14533197.pdf

Krupnick, Catherine G., Men and Women in the Classroom, Derek Bok Center for Teaching and Learning, Harvard University, 1985:  http://isites.harvard.edu/fs/html/icb.topic58474/krupnick.html

Robb, Alice, Why Women Get Interrupted More, -- Even By Other Women,  New Republic, May 14, 2014:  https://newrepublic.com/article/117757/gender-language-differences-women-get-interrupted-more

Cameron, Debbie, Why Women Talk Less, Debuk.Wordpress.com, May 23, 2015:  https://debuk.wordpress.com/2015/05/23/why-women-talk-less/