Astanga Hrudaya
अथ सम्पीडिते गर्भे योनिमस्याः प्रसारयेत्। मृदु पूर्वं प्रवाहेत बाढमाप्रसवाच्च सा॥८१॥
the woman should be made to lie on a cot, when the fetus is being squeezed out, her vagina should be dilated (by application of oil) she should be asked to bear down mildly in the beginning and forcebly afterwards till delivery;
english translation
atha sampIDite garbhe yonimasyAH prasArayet। mRdu pUrvaM pravAheta bADhamAprasavAcca sA॥81॥
hk transliteration by Sanscript