Jatakaparijata 13.61

13.61

atha janmadeśāḥ |
pūrṇe śaśini svarāśige saumye lagnagate śubhe sukhe |
lagne jalajo'stage'pi vā candre potagatā prasūyate ||

Now, the places of birth: / When the full Moon is in its own zodiacal sign, Mercury is in the ascendant, and a benefic is in the fourth house, / or when a watery planet is in the ascendant or in the seventh house while the Moon is there, the mother gives birth aboard a boat.