A follow-up study of the efficacy and safety of injectable microencapsulated megestrol acetate and a discussion on its contraceptive mechanism
Han, Z.Y.; Xiao, R.Q.
International Journal of Gynaecology and Obstetrics the Official Organ of the International Federation of Gynaecology and Obstetrics 23(3): 207-211
1985
ISSN/ISBN: 0020-7292 PMID: 2865183 DOI: 10.1016/0020-7292(85)90106-7Document Number: 414953
A monthly injectable microencapsulated contraceptive was developed by the researchers of the School of Pharmacy of Sichuan Medical College, and a comparative clinical study was undertaken by the Sichuan Cooperative Research Group. It has been found that the microencapsulated compound consisting of 15 mg megestrol acetate and 5 mg estradiol valerate is associated with the lowest incidences of menstrual disturbances and other side effects. This is a follow-up report on the 434 women who used this 'optional' dosage of compound by before-and-after comparisons and by comparisons with two other groups of women: 41 women who were given the compound with the same dosage combination but with microencapsular coat dissolved, and 20-30 women who were using a non-steroidal contraceptive method such as IUDs, barrier or rhythm methods. The microencapsulated compound was highly effective in preventing accidental pregnancies. All except two of the 119 women who discontinued the medication experienced normal menstruation within 3 months. The study did not show changes in blood pressure, liver function, glucose tolerance level and plasma concentration of cholesterol in women using the compound. Cervical smears and breast examination also showed no evidence of epithelial abnormality or breast tumors. This new delivery system of microencapsulated injections affects the cervical mucus function, and inhibits ovulation as well as implantation of fertilized ovum.