results from additional groups , nonpregnant ho females given 100 micrograms/kg eb and d16h animals ( females whose pregnancies were terminated by hysterectomy only and their ovaries left intact ) , both of which exhibit maternal behavior at 48 h , support the idea that a high level of nuclear estrogen receptors in the poa followed by a sustained high level is necessary for estrogen stimulation of maternal behavior .
C0032961
pregnancies
C0014939
estrogen