俱舍論記 9.38

9.38

「如是中有至或作不男」者，此明中有起顛倒心，義便復明住胎。隨前起貪面有向背，右勝左劣，故男右女左。又《正理》云「女、男串習左、右事故，宿因分別力使然故。言蘊厚者，漸堅厚也。餘文可知。

[On the passage] 'Such an intermediate existence... or become an eunuch (napuṃsaka)': this clarifies that the intermediate existence gives rise to an inverted mind, and in passing it also clarifies dwelling in the womb. Following the craving that arose previously, the face either faces toward or away; right is superior and left is inferior, so males face right and females face left. Furthermore, the *Nyāyānusāra* says: 'Because women and men are habituated to left and right actions, it is caused by the force of discrimination from past causes.' The phrase 'the aggregates become dense' means they gradually become hard and dense. The rest of the text is self-evident.