why is the female reproductive system more complex than the male reproductive system ?

The female reproductive system is more complex than the male's because the male needs only to produce and deliver gametes the female must do this as well as provide nutrition and safe harbor for fetal development and then give birth and nourish the infant. And female reproductive physiology is cyclic and female hormones are secreted in a more complex sequence compared to the relatively steady simultaneous secretion of regulatory hormones in the male.