Intermediate
Technical
IVT
Lightening
The descent of the fetal presenting part into the pelvis near term, causing the uterine fundus to lower.
Full Definition
Lightening, also known as 'dropping,' occurs when the fetal presenting part (usually the head) descends into the maternal pelvis in preparation for delivery. This typically happens 2-4 weeks before labor in first-time mothers and may occur during early labor in multiparous women. The phenomenon results in a lower, more anterior position of the uterine fundus, which may relieve upper abdominal pressure and improve maternal breathing and digestion. However, it may increase pelvic pressure and urinary frequency.
Usage
Usage note: Do not confuse with 'lightning' - refers to the sensation of lightness in upper abdomen.
In Context
- "The patient experienced lightening at 37 weeks, with improved breathing but increased pelvic pressure." — Prenatal examination note
- "Lightening may not occur until labor begins in multiparous patients." — Obstetric textbook
Also known as
dropping
engagement
Don't confuse with
labor onset
Braxton Hicks contractions