It is common for pregnant drow to carry twins or even triplets. Even in these cases, multiple births are rare, as the strongest of the fetuses feeds on its siblings in the womb. Pregnant drow can sometimes feel these mortal combats take place in their bellies. Such prenatal battles produce in their mothers a euphoric sensation, referred to in the Undercommon tongue as chad-zak. The feeling is infinitely stronger than that produced in the bedchamber or by any intoxicant. Without it, it is doubtful that drow women, selfish to the core, would ever deign to suffer the inconveniences of reproduction.
Chad-zak occurs up to four times per multiple pregnancy. It usually happens early in the third trimester. Mothers who experience repeated chad-zaks usually feel them in quick succession, once every one or two days. The final chad-zak indicates one fetus's successful slaying of its rivals. This process does not result in stillbirths; the slain are absorbed back into the mother's body.
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