Psalm 139:15 New English Translation

¹⁵my bones were not hidden from you,
when^[a] I was made in secret
and sewed together in the depths of the earth.^[b]

Psalm 139:15 tc The Hebrew term אֲשֶׁר (ʾasher, “which”) should probably be emended to כֲּאַשֶׁר (kaʾasher, “when”). The כ (kaf) may have been lost by haplography (note the kaf at the end of the preceding form).
Psalm 139:15 sn The phrase depths of the earth may be metaphorical (euphemistic) or it may reflect a prescientific belief about the origins of the embryo deep beneath the earth’s surface (see H. W. Wolff, Anthropology of the Old Testament, 96-97). Job 1:21 also closely associates the mother’s womb with the earth.

New English Translation (NET)