What is the nine months up, nine months down’ theory?

There are theories that if no longer breastfeeding, at around nine months postpartum, the mother’s body starts to ‘let go’ of the stored fat, to allow it to be lost through diet and exercise. Before then, for some women, depending on genes and many other contributing factors, trying to lose weight can be a futile uphill battle. Author Vicki Iovine calls it the ‘Nine Months Up, Nine Months Down’ theory.