Part of this difference may be due to women's less aversion to seeing therapists. Women's average reaction may be more functional in the long run than the average man's. Stoicism may have long-term or hidden consequences, but this is all speculated and ahs yet to be deomonstrated clearly. Women's increased vulnerability to grief and dysfunction after a loved one's death is mostly social. Women define themselves more in terms of their relationships with others.
Women are the primary caregivers.
Also, many women are dependent on others for financial support and social standing. Pregnancy loss is a uniquely female experience and has hormonal as well as emotional fall-out. When a woman's identity and self-image is too heavily emmeshed in the lost loved one, grief can become chronic and unresolving. Interaction and availability of the loved are essential for the woman's emotional functioning. The woman feels she is not strong, caring, or competent alone.