Human fertility is a particularly complex subject especially when it comes to female fertility. Curcumin has been found to be a weak phytoestrogen. A phytoestrogen is a molecule that is similar to estrogen in that it mimics its structure and action.
In female fertility, the balance between the hormones including progesterone and fertility is a delicate one. There is a school of thought that believes that taking phytoestrogens through one's diet may be deleterious to fertility (Are Phytoestrogens Good or Bad for You?). For example Tofu and Soya products are believed to be strong phytoestrogens and these products are thought to be disadvantageous because they are believed to create an over abundance of estrogen in the body. It is however important to note the distinctions previously made between weak and strong phytoestrogens. Some scientists believe that if levels of estrogen are too high, the use of a weak phytoestrogen such as curcumin would occupy the estrogen receptor site and thus in return lessen the amount of estrogen received (Can Phytoestrogens Boost IVF Success Rates?).