Do wearable pumps cause less output than traditional pumps?

Yes, on average. Specialist subreddit consensus and lactation-focused blogs we read consistently note that wearables yield less milk per session than a hospital-strength plug-in pump, partly due to suction strength and partly due to the angle and fit of in-bra cups. Heated wearables like the eufy S1 Pro narrow the gap for some users, but for building or maintaining supply, a traditional pump is still the default recommendation.