AKA "Groaning" chairs were used in birthing.
Here is a site with some pictures of period parturition chairs.
Alternatively, Webster's Online Dictionary defines groaning chairs as:
Groaning chair. The chair in which a woman is confined or sits afterwards to receive congratulations. Similarly "groaning cake" and "groaning cheese" are the cake and cheese which used to be provided in "Goose month."
"For a nurse, the child to dandle,
Sugar, soap, spiced pots, and candle
A groaning chair, and eke a cradle"
Poor Robin's Almanack, 1676. Source: Brewer's Dictionary.
Also: Groaning Malt A strong ale brewed for the gossips who attend at the birth of a child, and for those who come to offer to a husband congratulations at the auspicious event.