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Abstract
The clinical performance and the in vivo release rate of a single 4-cm Nestorone™
1Nestorone™ is the Population Council trademark for 16-methylene-17-alpha-acetoxy-19 norprogesterone,
previously known as ST 1435.
subdermal implant were investigated. Implants manufactured by two different procedures
were compared. Volunteers were 70 healthy women of proven fertility. Forty women provided
blood samples twice a week in the pretreatment cycle and for 5–6 weeks at 6-month
intervals during treatment. Additional control cycles (n = 31) were studied in 19
Copper T users.No pregnancy occurred in 1570 woman-months. Nesterone™ plasma levels (X ± S.E.) declined from 112 ± 8 to 86 ± 3 pmol/L (Implant A) and from
145 ± 8 to 57 ± 5 pmol/L (Implant B) from the first to the 24th month. Progesterone
levels were <9.5 nmol/L in 166 (93%) of 178 blood samplings taken during treatment.
Progesterone levels >16 nmol/L were found in only 7 sampling periods (3.9%) in treated
women and in 70 (98.6%) out of 71 control cycles. No ovulation occurred with Nestorone™ plasma levels above 105 pmol/L.
No abnormal changes were observed in plasma lipoproteins or other clinical chemistry
parameters during treatment. The implants were well tolerated. The most frequent complaint
was the occurrence of irregular bleeding. Enlarged follicles found during pelvic examination
in 8 subjects (11.4%) disappeared spontaneously in 10 days to 6 weeks.
Implants were removed because of medical (n = 10, 14.3%) or personal reasons (n =
6, 8.6%) or at the 24th month of treatment (n = 54, 77.1%). The estimated average
daily in vivo release rate of Nestorone™ was 45–50 μg/day.
A single Nestorone™ subdermal implant affords efficient contraceptive protection during two years.
Keywords
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References
- Fertility control with subdermal Silastic capsules containing a new progestin (ST 1435).Int J Fertil. 1976; 21: 103-108
- Contraception with subcutaneous capsules containing ST 1435. Pituitary and ovarian function and plasma levels of ST-1435.Contraception. 1981; 23: 63-75
- ST-1435: Development of an implant.in: Zatuchni GI Goldsmith A Shelton HD Sciarra JJ Long-Acting Contraceptive Delivery Systems. Harper & Row, Philadelphia1984: 441-449
- Contraception with single implants and mini-implants of ST-1435.in: Zatuchni GI Goldsmith A Shelton HD Sciarra JJ Long-Acting Contraceptive Delivery Systems. Harper & Row, Philadelphia1984: 450-455
- Contraception with subdermal implants releasing the progestin ST-1435: A dose-finding study.Contraception. 1992; 45: 49-55
- A contraceptive subdermal implant releasing the progestin ST-1435: Ovarian function, bleeding patterns and side effects.Fertil Steril. 1992; 51: 142-147
Laurikka-Routti M. Serum lipids, blood pressure, body weight and serum chemistry in women using subcutaneous contraceptive implants releasing the progestin ST-1435. Obstet Gynecol (in press).
- Milk and plasma concentrations of the progestin ST 1435 in women treated parenterally with ST 1435.Contraception. 1990; 42: 555-562
- 11th Ed. Programme for the Provision of Matched Assay Reagents for the RIA of Hormones in Reproductive Physiology. Method Manual. 1987
- A simplified method for the estimation of total cholesterol in serum and demonstration of its specificity.J Biol Chem. 1952; 195: 357-366
- Separation of serum high density lipoproteins for cholesterol determination. Ultracentrifugation vs precipitation with sodium phosphotungstate and magnesium chloride.Clin Chem. 1981; 27: 838-841
- Determination of serum triglycerides.J Atheroscl Res. 1963; 3: 334-336
- Studies on the duration of egg transport by the human oviduct. II. Ovum location at various intervals following the LH peak.Amer J Obstet Gynecol. 1978; 132: 629-634
- Hormonal effects of the 300 ug norethisterone (NET) minipill. 1. Daily steroid levels in 43 subjects during a pretreatment cycle and during the second month of NET administration.Contraception. 1980; 21: 87-113
- Ultrasound demonstration of increased frequency of functional ovarian cysts in women using progestogen-only oral contraception.Br J Obstet Gynecol. 1985; 92: 1003-1009
Article info
Publication history
Accepted:
October 3,
1994
Received in revised form:
September 27,
1994
Received:
October 27,
1993
Identification
Copyright
© 1995 Published by Elsevier Inc.
