What is the Pro Care Maternity Belt? A comfortable elastic belt to support the bump & treat back pain & Sacro Iliac joint pain during pregnancy. When can I use it? During all stages of pregnancy. Which size do I need? Measure around the hips. If you are between sizes, please choose the larger size. Small 80-105cm (32"-42") Medium 105-130cm (42"-52") Large 130-155cm (52"-62") X-Large: 155-180cm (62-72") How does it work? The Pro Care Maternity Belt provides support for the lower back & Sacro Iliac joint (SI joint), as well as the bump. Hormonal changes during pregnancy produce lax ligaments which mean that expectant mothers commonly suffer from SI joint dysfunction & lower back pain, such as Sciatica, a herniated disc & posture related back ache. Further stress can be put on the lower back & Sacro Iliac joint as a result of the babys growth & the subsequent expansion of the mothers tummy. The Pro Care Maternity Belt provides the ideal solution as it supports the bump as well as the lower back & Sacro Iliac joint. This is very effective in relieving aches & pains during pregnancy.