One verse

Srimad Bhagavatam 3.31.2

3.31.2

कललं त्वेकरात्रेण पञ्चरात्रेण बुद्बुदम् । दशाहेन तु कर्कन्धू: पेश्यण्डं वा तत: परम् ॥ २ ॥

kalalam tv eka-ratrena panca-ratrena budbudam dasahena tu karkandhuh pesy andam va tatah param

kalalam
mixing of the sperm and ovum
tu
then
eka-ratrena
on the first night
panca-ratrena
by the fifth night
budbudam
a bubble
dasa-ahena
in ten days
tu
then
karkandhuh
like a plum
pesi
a lump of flesh
andam
an egg
va
or
tatah
thence
param
afterwards.

On the first night, the sperm and ovum mix, and on the fifth night the mixture ferments into a bubble. On the tenth night it develops into a form like a plum, and after that, it gradually turns into a lump of flesh or an egg, as the case may be.