Men, not hormones, may be to blame for premenstrual syndrome (PMS).
University of Western Sydney researchers and Relationships Australia are teaming up to pilot a national study into how relationship problems contribute to PMS, which affects about 90 per cent of women.
The initial part of the study involves the questioning of 10 lesbian couples and 10 heterosexual couples, to see if PMS is less severe when a relationship involves two women.
"If you've got a woman partner who has premenstrual experiences is she going to be more understanding?" said Jane Ussher, professor of women's health psychology at the University of Western Sydney.
"Certainly, anecdotally, that's what we've seen and we're going to look at it systematically.
"There were certainly some things that partners were doing that made (the PMS) worse in some instances.
"Men certainly play a significant role in (PMS) and can play a very significant role in women's depression and anger and frustration at that time of the cycle."
Ten to 40 per cent of women experience moderate to severe PMS and up to ten per cent are believed to experience the most severe form, premenstrual dysphoric disorder, which is classified as a psychiatric disorder in the US.
PMS and PMDD cover a range of about 150 physical and psychological symptoms, but women most often seek help for depression, anxiety, irritability and anger.
Prof Ussher spent three years studying 108 British women who suffered premenstrual symptoms.
A third of the subjects were on Prozac - the treatment of choice for PMS - a third were receiving psychological therapy, and the remainder were getting both.
She said the study showed that psychological factors were just as important as biological issues in PMS, and maybe even more significant.
"A classic case of PMS is a woman who's working full time, looking after everyone at home, picking up the shopping after work, picking up the kids from school, finding very little space for themselves," she said.
"Women are able to keep up this superwoman (performance) three weeks a month but premenstrually they're not able or willing to do it anymore.
"They either just withdraw and feel depressed or they can become very angry with the family.
"I would say that isn't biological - it's to do with what's happening in the family and the relationship."
Prof Ussher said all women experienced hormonal and neurotransmitter changes during their cycle, but not all women got PMS.
"Women who get symptoms are biologically no different to women who don't," she said.
"What actually causes the negative symptoms is a combination of psychological factors - what's happening in your body and what's happening in your environment.
"What we've shown in the research is that if you get women to change other factors the biological component isn't particularly strong at all."
She said her research also found if a partner was supportive, understanding and gave a woman space she coped with her PMS better.
However, trivialising the experience or getting angry at the woman only made it worse.