Which of the following is not an adverse effect of clomiphene citrate?

Clomiphene has estrogen antagonistic action in pituitary and hypothalamus (reduces feedback inhibition of GnRH secretion). It is used for the treatment of anovulatory infeility by increasing GnRH release. Major adverse effect is hyperstimulation syndrome (polycystic ovarian disease) and multiple pregnancy. Estrogen antagonistic action is also responsible for hot flushes.