Colic occurs in both breastfed and formula-fed babies and should never be a reason to stop breastfeeding. If baby has been diagnosed with "colic," this basically means that he's hurting and the doctors don't know why. (Stinks. We know.) Doctors, scientists, and moms are constantly searching for answers, and sometimes different treatment measures seem to help different babies.
If you feel that baby's colic is triggered at feeding time, here are a few possibilities to consider:
It is believed that if baby gets too much foremilk (the thin milk that comes first from your breast) and not enough hindmilk (the fattier milk that comes later), he can wind up with more lactose in his gut than his body can handle. The excess lactose can ferment, leading to gas, bloating, and big (loud) green poops. Moms can remedy this by feeding baby from one breast until baby is totally finished with it before switching. That way, baby's sure to get the fatty hindmilk. It may also help to do breast compressions to help baby take in more hindmilk.
Some moms run into this same issue because of an oversupply of milk. (Baby gets full before getting to the hindmilk.) In this case, it may help to limit feedings to one breast or to do "block feedings" for a day or two, nursing from one breast for a certain block of hours before switching to the other breast. (For example, nursing from the left breast for feedings between 8 a.m. and 12 p.m., the right breast for feedings between 12 p.m. and 4 p.m., and so on.) Block-feeding should help tame mom's supply to match baby's needs.
Sometimes mom has a strong milk ejection reflex. In this case, the milk "lets down," baby gets too much milk too fast (he might choke and sputter), causing him to gulp and swallow air, which in turn makes for a gassy, hurting tummy. Overactive let-down is usually tied to an oversupply of milk, and the same remedies listed above can help. It might also help to take baby off the breast while your milk lets down and to let the milk spray into a clean cloth for a few minutes before latching baby back on.
Babies can also swallow air if they don’t have a good seal on the breast. Make sure baby is latched deeply and that you don't hear any clicking sounds (which could mean baby is breaking suction with each suck).
And, of course, you can help get out extra air by perfecting your burping techniques. If baby seems full of air, burp him more often.
Food Sensitivity / Allergy
Some babies are sensitive to a foreign protein in their mom's diet. The most commonly diagnosed sensitivity is to a protein found in cow's milk, which can cause all sorts of gastrointestinal discomforts (aka colic symptoms). If you think baby could have a food sensitivity, talk to your doctor about trying an elimination diet for a few weeks.
Gastroesophageal Reflux (GER)
With GER, the muscular valve between baby's esophagus and stomach isn’t strong enough, and acidic stomach contents can come back up, which can burn. (Ouch.) Signs include fussiness after eating, frequent spit ups, tummy pain, frequent and unexplained wheezing and chest infections, waking at night in pain, and throaty sounds after nursing. For true GER, a doctor can prescribe medicines to help, and parents are advised to keep baby upright and quiet for at least 30 minutes after each feeding (to help keep the milk down). Keep breastfeeding. Studies show GER is less severe in breastfed babies.