Nipple flow rate affects how fast milk comes out. Wrong flow causes problems: Too slow = frustration, long feeds, giving up. Too fast = choking, gulping, gas, overfeeding, bottle preference over breast. Flow levels: Preemie/newborn (slowest), Level 1 (slow, 0-3 months), Level 2 (medium, 3-6 months), Level 3+ (fast, 6+ months). Breastfed babies should usually stay on slow flow longer. Nipple shape also matters: Standard, wide-base (like breast), orthodontic, angled. May need to try different brands to find what baby prefers.

Baby won't take bottle even when hungry. Common when breastfed baby needs to take bottle (return to work). Also happens during teething, illness, or developmental leaps. Tips: Have someone else give bottle (baby may refuse if they smell milk on you), try different nipples/bottles, try when baby is calm (not starving), try different positions, don't force it.

Engorgement: Breasts become overly full, hard, painful, and swollen (usually days 2-5 postpartum when milk comes in). Makes latching difficult for baby. Normal engorgement resolves in 24-48 hours with frequent feeding. Mastitis: Breast infection, often starts with clogged duct. Symptoms: Red, hot, painful wedge-shaped area on breast, fever >101°F, flu-like aches, chills. Requires antibiotics. Mastitis is urgent - untreated can lead to abscess. Usually affects one breast, most common in first 3 months of breastfeeding.