Tablets: This is the most common type of HRT and contains low doses of estradiol and progesterone.   Injections: This type of HRT uses a small needle to inject small amounts of hormones directly into the fatty tissues under the skin. It is recommended for women who are not able to take tablets or who have difficulty with injection procedures.   Biological: This type of HRT uses bio-identical hormones that are identical to the hormones produced by the body. It is the most effective form of HRT, and requires a prescription from a healthcare provider.   Skin patches: This type of HRT uses a patch that releases small doses of hormones into the skin. It is recommended for women who are unable to take tablets or injections, have difficulty with injection procedures, or have concerns about side effects from pills and injections.    Oestrogen gel: This type of HRT is applied to the skin as a patch and contains doses of estrogen and progesterone. It is recommended for women who are not able to take tablets or injections, have difficulty with injection procedures, or have concerns about side effects from pills and injections.   Implants: This type of HRT uses small implanted pellets that release hormones continuously into the body. It is recommended for women who are not able to take tablets or injections, have difficulty with injection procedures, or have concerns about side effects from pills and injections.    Vaginal oestrogen: This type of HRT is inserted into the vagina and releases oestrogen into the body. It is recommended for women who do not have a uterus and do not want to use hormonal contraception.    Testosterone: This type of HRT is available in injectable form and is used to treat women who have low levels of testosterone due to menopause, chemotherapy, or radiation therapy.