I found this simple pattern on a chat site for baby-wearing mothers and translated it into English. It's not a nipple cover, more of a breast pad, and here they are often knit in natural wool with lanolin, as are soakers (ask your grandma if you don't know what they are!).

The sender writes:
Pattern for breast pads, knitted in the round 1. Cast on 6 st on three double-pointed needles (the sender used no.4 or 4.5 because she knits tightly).
2. Knit one round.
3. On next round, increase one st between each existing st, to 12 st, 4 on each needle.
4. Knit one round.
5. Increase by one st in the first and third st on each needle, to 18 st, 6 per needle.
6. Knit one round.
7. Increase by one stitch in the first and the center stitch on each needle, to 24 st, 8 per needle.
Continue in this way until you reach the desired size.  Cast off, fasten ends.  The sender knit hers in 'Fine Alpaca' yarn.

I guess you could consider this along the lines of a tea cozy :-)  FWIW I have met many women with Raynauds who have had no effect from wool breast pads, but a lot of mothers like them because they stay warm even when wet, and in our climate that counts for something.

Cheers
Rachel Myr
Kristiansand, Norway

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