Progestogen-only injectable contraceptive
| Long-acting reversible contraceptives (LARC) | |
|---|---|
| Background | |
| Type | Hormonal |
| First use | 1957[1] |
| Pregnancy rates (first year) | |
| Perfect use | 0.2% |
| Typical use | 6% |
| Usage | |
| Reversibility | Yes |
| User reminders | ? |
| Advantages and disadvantages | |
| STI protection | No |
Progestogen-only injectable contraceptives (POICs) are a form of hormonal contraception and progestogen-only contraception that are administered by injection and providing long-lasting birth control.[2][3] As opposed to combined injectable contraceptives, they contain only a progestogen without an estrogen, and include two progestin preparations:[2][3]
- Medroxyprogesterone acetate (brand names Depo-Provera, Provera, Depo-subQ Provera 104)[4] – 150 mg (intramuscularly) or 104 mg (subcutaneously) every 3 months[3]
- Norethisterone enanthate (brand names NET EN, Noristerat, Norigest, Doryxas)[5] – 200 mg (intramuscularly) every 2 months[3]
Mechanism of Action
[edit]These POICs work by providing an influx of progesterone into the female body. This influx will signal to the body that it does not need to synthesize its own hormones to induce the cycle. Since the body does not release any hormones of its own, there are no fluctuations in levels to trigger the phases in menstruation and ovulation does not occur. [6]
Potential Side Effects
[edit]As will all birth control medications, certain side effects may occur from taking the hormonal supplements. Changes in menstrual bleeding may occur, such as a lighter flow or complete stop to the regular monthly menses, or abnormal bleeding throughout the cycle. Others have reported small weight gain, and increase in headaches or mood swings, and a decrease in libido.[6]
Links to Cancer
[edit]Some research has shown that women who have taken hormonal birth controls could possible be less likely to develop certain cancers, such as endometrial, cervical, and ovarian.[7] This is likely due to the fact that the hormonal birth controls stop the monthly cycle of injury and repair to the endometrial tissue. This consistent injury to the uterine tissues is thought to be a factor in developing certain cancers, so if it is stopped for a period of time, the tissue will be less damaged that that of someone who has never taken birth control.
On the contrary, it was shown that women who has previously or were currently taking a hormonal birth control had an increased risk in developing breast cancer. This risk decreased as the individuals stopped the birth control, but no data was found linked to the duration of time one was taking a contraceptive. [7]
Research
[edit]Progestogens that have been studied for potential use as POICs but were never marketed as such include the progesterone derivatives algestone acetophenide (dihydroxyprogesterone acetophenide) (100 mg/month), chlormadinone acetate (250 mg/3 months), hydroxyprogesterone caproate (250–500 mg/month), gestonorone caproate (2.5–200 mg/1–2 months), and oxogestone phenpropionate (50–75 mg/month), and the testosterone derivatives lynestrenol phenylpropionate (25–75 mg/month), levonorgestrel butanoate, levonorgestrel cyclobutylcarboxylate, and levonorgestrel cyclopropylcarboxylate.[8][9] Some of these have been introduced for use in combined injectable contraceptives instead.[8][10][11]
See also
[edit]References
[edit]- ^ Singh M, Saxena BB, Singh R, Kaplan J, Ledger WJ (1997). "Contraceptive efficacy of norethindrone encapsulated in injectable biodegradable poly-dl-lactide-co-glycolide microspheres (NET-90): phase III clinical study". Advances in Contraception. 13 (1): 1–11. doi:10.1023/a:1006519027168. PMID 9181181. S2CID 44918557.
In 1957, Karl Junkmann developed norethindrone enanthate (NET-EN or Noristeroir), the first injectable contraceptive which was injected every two months [1].
- ^ a b P. F. A. van Look; Kristian Heggenhougen; Stella R. Quah (January 2011). Sexual and Reproductive Health: A Public Health Perspective. Academic Press. pp. 82–. ISBN 978-0-12-385009-6.
- ^ a b c d Nagrath Arun; Malhotra Narendra; Seth Shikha (15 December 2012). Progress in Obstetrics and Gynecology--3. Jaypee Brothers Medical Publishers Pvt. Ltd. pp. 416–. ISBN 978-93-5090-575-3.
- ^ Mary Lee; Archana Desai (2007). Gibaldi's Drug Delivery Systems in Pharmaceutical Care. ASHP. pp. 328–. ISBN 978-1-58528-136-7.
- ^ Chaudhuri (1 January 2007). Practice Of Fertility Control: A Comprehensive Manual (7Th ed.). Elsevier India. pp. 154–. ISBN 978-81-312-1150-2.
- ^ a b Hospital, The Royal Women's. "Depo Provera". The Royal Women's Hospital. Retrieved 2024-04-17.
- ^ a b "Oral Contraceptives (Birth Control Pills) and Cancer Risk". www.cancer.gov. March 1, 2018. Retrieved 2024-04-17.
- ^ a b Mokhtar K. Toppozada (1983). "Monthly Injectable Contraceptives". In Alfredo Goldsmith; Mokhtar Toppozada (eds.). Long-Acting Contraception. pp. 93–103. OCLC 35018604.
- ^ Dr. S. S. Kadam (July 2007). PRINCIPLES OF MEDICINAL CHEMISTRY Vol. - II. Pragati Books Pvt. Ltd. pp. 381–. ISBN 978-81-85790-03-9.
- ^ Benagiano, G., & Merialdi, M. (2011). Carl Djerassi and the World Health Organisation special programme of research in human reproduction. Journal für Reproduktionsmedizin und Endokrinologie-Journal of Reproductive Medicine and Endocrinology, 8(1), 10-13. http://www.kup.at/kup/pdf/10163.pdf
- ^ Toppozada M (June 1977). "The clinical use of monthly injectable contraceptive preparations". Obstet Gynecol Surv. 32 (6): 335–47. doi:10.1097/00006254-197706000-00001. PMID 865726.