Your breastmilk is produced on a supply and demand basis. The more frequently your baby feeds and the more milk they drink, the more milk your body will produce. There is always some milk in your breasts and they are always producing more, so you can breastfeed even if your breasts feel “empty”. Stimulating your breasts by feeding your baby tells your body to make more milk. By contrast, when your breasts become very full or engorged, a hormone called feedback inhibitor of lactation (FIL) tells your body to stop making milk. As milk leaves your breasts FIL levels drop and your breasts starts producing milk again. This means that more you feed, the more milk your breasts will produce, while allowing your breasts to become very full in between feeds can cause your milk supply to drop. This is why responsive breastfeeding is the best way to establish a good milk supply, whilst attempting to feed to a schedule or to space breastfeeds out can reduce your milk supply.
If you are expressing for your new baby rather than feeding at the breast you should ideally start expressing as early as possible (within 2 hours of birth) and try and ensure that you are expressing as frequently and as effectively as possible. This will help to increase your milk supply. Ideally, you should aim to express at least 8-10 times in a 24-hour period. Expressing frequently is more important than expressing at regular intervals. This means you can fit in expressing times to suit you, rather than trying to express on a set schedule. It is particularly important that you express at least once during the night. This is because the levels of the hormone prolactin, which drives milk production, are higher overnight. Prolactin levels seem to be highest between 2-6am.
Using a dummy or pacifier to settle your baby can hide some of their early feeding cues, interfering with responsive breastfeeding. For this reason, it is suggested that breastfeeding mums try not to introduce a dummy until their baby is a least 6 weeks old, and breastfeeding has been established. You can find more information on using a dummy from NHS start4life and The Lullaby Trust.