Here are some ideas to help a baby deal with a forceful letdown and fast milk flow (from kellymom.com) ...
Position baby so that she is nursing "uphill" in relation to mom's breast, where gravity is working against the flow of milk.
The most effective positions are those where baby's head and throat are above the level of your nipple. Some nursing positions to try:
• Cradle hold, but with mom leaning back (a recliner or lots of pillows helps)
• Football hold, but with mom leaning back
• Elevated football hold - like the football hold, but baby is sitting up and facing mom to nurse instead of lying down (good for nursing in public).
• Side lying position - this allows baby to dribble the extra milk out of her mouth when it's coming too fast
• Australian position (mom is "down under", aka posture feeding) - in this position, mom is lying on her back and baby is on top (facing down), tummy to tummy with mom. Avoid using this positioning frequently, as it may lead to plugged ducts.
• Burp baby frequently if she is swallowing a lot of air.
• Nurse more frequently. This will reduce the amount of milk that accumulates between feedings, so feedings are more manageable for baby.
• Nurse when baby is sleepy and relaxed. Baby will suck more gently at this time, and the milk flow will be slower.
• Wait until let-down occurs, then take baby off the breast while at the same time catching the milk in a towel or cloth diaper. Once the flow slows, you can put your baby back to the breast.
• Pump or hand express until the flow of milk slows down, and then put baby to the breast. Use this only if nothing else is working, as it stimulates additional milk production
. If you do this, try to express a little less milk each time until you are no longer expressing before nursing.