The menstrual cycle in normal adult woman is of
$48$ days
$38$ days
$18$ days
$28$ days
Changes in $GnRH$ pulse frequency in femail is controlled by circulating levels of
Why are menstrual cycles absent during pregnancy ?
The substance secreted by the corpus luteum is
Proliferation of endometrium of uterus in controlled by
Ovulation does not occur during pregnancy in the human female because