Studies show that fennel reduces the body’s production of oxytocin and prostaglandin, two hormones that can cause painful periods. Fennel seed oil has also been shown to soothe the symptoms of colic.
Remove outer layer and stems of fennel bulbs. Cut bulbs in half lengthwise, from stem end through core. Remove core, then, using a mandoline or sharp knife, thinly slice fennel lengthwise.