Some women can actually donate platelets although some women can't donate platelets due to the potential presence of HLA antibodies in some female platelet donors.
The antibodies that female platelet donors may have are not harmful to the woman herself, but can cause complications in people receiving platelet transfusions.
Pregnancy can also trigger the development of HLA antibodies in some women, and the antibodies develop when a woman's body is exposed to fetal blood during pregnancy.
The antibodies can sometimes lead to a rare but also serious condition that is called TRALI, also known as Transfusion related acute lung injury in people that receive the platelet transfusions.
And blood donation organizations such as OneBlood also screen the female platelet donors, especially the females that have a history of pregnancy for the HLA antibodies.
And if the female tests negative for the antibodies, then the female is often eligible and able to donate the platelets.
Also many women can still donate their platelets, even if they have been pregnant, as long as they test negative for the HLA antibodies.
The focus is mainly on testing and also identifying women that may be at risk of causing complications and not just a complete ban on women who donate platelets.
So women can sometimes donate platelets but it can vary.