Hi Grace
You have been trained to provide certain types of treatment. Look at your qualification certificate. This will tell you what types of treatment you can insure yourself for.
You then need to make sure that your insurance schedule lists the qualifications that you have gained. You need to check the policy schedule and the policy wording to check the definitions of the treatments listed in your schedule. You need BOTH the qualification and the insurance certification
It won't be possible for you to be insured to provide any treatment which goes beyond your training - even if you pay for the insurance cover. Your insurance will cover you for the treatments which relate to your training, not something that you have invented for yourself based on your experience and expertise. As you haven't covered pregnancy massage, you won't be insured on your Guild insurance to treat pregnant women at any stage of their pregnancy, EVEN if your policy states that you have this cover
Deep tissue massage is not just about applying pressure with your forearms, it's more of a level 4/5 qualification. A good level three course will teach you some deep tissue techniques which you can do safely. And these are usually covered by a Swedish massage qualification insurance - just check to be on the safe side.
If you are applying traction, using stretching techniques, sliding your fingers between or under muscles to reach deeper tissues or doing trigger point work - you need deep tissue training, a qualification AND deep tissue insurance cover.
Some insurance policies do give you more comprehensive cover without post graduate qualifications - but these policies are offered to people with an insurance approved level four and over qualification.