This works for me down to about -15 C and a regular cycling helmet. Below that I'll switch to a heavily vented snowboard helmet.
Popular alternatives to
Windproof Skull Cap Winter ...
AZMED Maternity Belly Band for Pregnant Women | Pregnancy Belly Support Band for Abdomen, Pelvic, Waist, & Back Pain | Adjustable Maternity Belt | For All Stages of Pregnancy & Postpartum (Beige)