Combined injectable birth control
Combined injectable contraceptives (CICs) are a form of hormonal birth control for women. They consist of monthly injections of combined formulations containing an estrogen and a progestin to prevent pregnancy.
| Combined injectable birth control | |
|---|---|
| Background | |
| Type | Hormonal |
| First use | By 1969 |
| Failure rates (first year) | |
| Perfect use | 0–0.2% |
| Typical use | ? |
| Usage | |
| Duration effect | 1 month |
| User reminders | ? |
| Advantages and disadvantages | |
| STI protection | No |
| Benefits | Especially good if poor pill compliance |
CICs are different from progestogen-only injectable contraceptives (POICs), such as depot medroxyprogesterone acetate (DMPA; brand names Depo-Provera, Depo-SubQ Provera 104) and norethisterone enantate (NETE; brand name Noristerat), which are not combined with an estrogen and are given once every two to three months instead of once a month.
Hormonal contraception works primarily by preventing ovulation, but it may also thicken the cervical mucus inhibiting sperm penetration. Hormonal contraceptives also have effects on the endometrium, that theoretically could affect implantation.