I've been told by people higher up than me that rounded corners are feminine and women like rounded corners. I'm female and I find this idea strange. But I don't want to debate based on bias and personal anecdotes. I'm looking for some actual user data supporting or debunking the idea that women prefer rounded corner designs.
In essence, there is a theory to support that women prefer rounded borders, but not because they are women - simply because they are humans.
The Contour Bias, often contributed to this research, states that people tend to favour objects with contours over objects with sharp angles or points. But there is no indication of gender differences (later research asserts that this has been observed with both female and male subjects; also related research clearly exhibit gender differences when these exist, like male's stronger preference for symmetry).
I think your superiors mixed the Contour Bias with the Anthropomorphic Form principle, in which human-like curves increase the appeal of designs (like with the Mae West bottle below). But I would not consider rounded corners as anything Anthropomorphic.
The Anthropomorphic Form principle is partly explained by the resemblance of curvy designs to female breasts and pregnancy bumps. There is also a mentioning of some differences in how the two genders interpret the design (for instance, sexuality for men, nuturing for females).