The Experts below are selected from a list of 81 Experts worldwide ranked by ideXlab platform
Kathryn M Curtis - One of the best experts on this subject based on the ideXlab platform.
-
when can a woman have repeat progestogen only injectables depot medroxyprogesterone acetate or Norethisterone Enantate
Contraception, 2009Co-Authors: Melissa E Paulen, Kathryn M CurtisAbstract:Abstract Background Currently, there is a generally accepted 2-week grace period for women returning early/late for reinjection of either depot medroxyprogesterone acetate (DMPA) or Norethisterone Enantate (NET-EN). This systematic review evaluates the evidence regarding return to fertility and ovulation after injection of a progestogen-only contraceptive. Study Design We searched the PubMed database to identify all relevant evidence published in peer-reviewed journals from database inception through November 2008 regarding timing of fertility and return to ovulation after the last injection of DMPA or NET-EN. Results We identified 20 articles, 10 on DMPA use, eight on NET-EN use and two examining both types of injectables. Six studies examining time to pregnancy after discontinuing DMPA or NET-EN reported that pregnancy rates during the currently recommended 2-week grace period were zero or very low. Studies of return to ovulation indicated a wide variation in time to ovulation post-injection with the majority ranging from 15–49 weeks from the last injection (for DMPA) and 4.9–24.3 weeks from the last injection (for NET-EN). Limitations of this body of evidence include small sample sizes, lack of data on the main outcome of interest (time to pregnancy) and inconsistency in measurement of ovulation, a surrogate measurement for pregnancy risk. Conclusion Studies evaluating time to pregnancy after last injection of DMPA or NET-EN reported extremely low pregnancy rates during the 2-week interval following the reinjection date; extremely low pregnancy rates for DMPA were also reported for 4 weeks following the reinjection date. Studies of return to ovulation after last injection of DMPA generally found that the earliest ovulation did not occur until several months after the last injection while studies of NET-EN reported ovulations around (or even before) the time for reinjection.
-
review article when can a woman have repeat progestogen only injectables depot medroxyprogesterone acetate or Norethisterone Enantate
2009Co-Authors: Melissa E Paulen, Kathryn M CurtisAbstract:Background: Currently, there is a generally accepted 2-week grace period for women returning early/late for reinjection of either depot medroxyprogesterone acetate (DMPA) or Norethisterone Enantate (NET-EN). This systematic review evaluates the evidence regarding return to fertility and ovulation after injection of a progestogen-only contraceptive. Study Design: We searched the PubMed database to identify all relevant evidence published in peer-reviewed journals from database inception through November 2008 regarding timing of fertility and return to ovulation after the last injection of DMPA or NET-EN. Results: We identified 20 articles, 10 on DMPA use, eight on NET-EN use and two examining both types of injectables. Six studies examining time to pregnancy after discontinuing DMPA or NET-EN reported that pregnancy rates during the currently recommended 2-week grace period were zero or very low. Studies of return to ovulation indicated a wide variation in time to ovulation post-injection with the majority ranging from 15–49 weeks from the last injection (for DMPA) and 4.9–24.3 weeks from the last injection (for NET-EN). Limitations of this body of evidence include small sample sizes, lack of data on the main outcome of interest (time to pregnancy) and inconsistency in measurement of ovulation, a surrogate measurement for pregnancy risk. Conclusion: Studies evaluating time to pregnancy after last injection of DMPA or NET-EN reported extremely low pregnancy rates during the 2-week interval following the reinjection date; extremely low pregnancy rates for DMPA were also reported for 4 weeks following the reinjection date. Studies of return to ovulation after last injection of DMPA generally found that the earliest ovulation did not occur until several months after the last injection while studies of NET-EN reported ovulations around (or even before) the time for reinjection.
Melissa E Paulen - One of the best experts on this subject based on the ideXlab platform.
-
when can a woman have repeat progestogen only injectables depot medroxyprogesterone acetate or Norethisterone Enantate
Contraception, 2009Co-Authors: Melissa E Paulen, Kathryn M CurtisAbstract:Abstract Background Currently, there is a generally accepted 2-week grace period for women returning early/late for reinjection of either depot medroxyprogesterone acetate (DMPA) or Norethisterone Enantate (NET-EN). This systematic review evaluates the evidence regarding return to fertility and ovulation after injection of a progestogen-only contraceptive. Study Design We searched the PubMed database to identify all relevant evidence published in peer-reviewed journals from database inception through November 2008 regarding timing of fertility and return to ovulation after the last injection of DMPA or NET-EN. Results We identified 20 articles, 10 on DMPA use, eight on NET-EN use and two examining both types of injectables. Six studies examining time to pregnancy after discontinuing DMPA or NET-EN reported that pregnancy rates during the currently recommended 2-week grace period were zero or very low. Studies of return to ovulation indicated a wide variation in time to ovulation post-injection with the majority ranging from 15–49 weeks from the last injection (for DMPA) and 4.9–24.3 weeks from the last injection (for NET-EN). Limitations of this body of evidence include small sample sizes, lack of data on the main outcome of interest (time to pregnancy) and inconsistency in measurement of ovulation, a surrogate measurement for pregnancy risk. Conclusion Studies evaluating time to pregnancy after last injection of DMPA or NET-EN reported extremely low pregnancy rates during the 2-week interval following the reinjection date; extremely low pregnancy rates for DMPA were also reported for 4 weeks following the reinjection date. Studies of return to ovulation after last injection of DMPA generally found that the earliest ovulation did not occur until several months after the last injection while studies of NET-EN reported ovulations around (or even before) the time for reinjection.
-
review article when can a woman have repeat progestogen only injectables depot medroxyprogesterone acetate or Norethisterone Enantate
2009Co-Authors: Melissa E Paulen, Kathryn M CurtisAbstract:Background: Currently, there is a generally accepted 2-week grace period for women returning early/late for reinjection of either depot medroxyprogesterone acetate (DMPA) or Norethisterone Enantate (NET-EN). This systematic review evaluates the evidence regarding return to fertility and ovulation after injection of a progestogen-only contraceptive. Study Design: We searched the PubMed database to identify all relevant evidence published in peer-reviewed journals from database inception through November 2008 regarding timing of fertility and return to ovulation after the last injection of DMPA or NET-EN. Results: We identified 20 articles, 10 on DMPA use, eight on NET-EN use and two examining both types of injectables. Six studies examining time to pregnancy after discontinuing DMPA or NET-EN reported that pregnancy rates during the currently recommended 2-week grace period were zero or very low. Studies of return to ovulation indicated a wide variation in time to ovulation post-injection with the majority ranging from 15–49 weeks from the last injection (for DMPA) and 4.9–24.3 weeks from the last injection (for NET-EN). Limitations of this body of evidence include small sample sizes, lack of data on the main outcome of interest (time to pregnancy) and inconsistency in measurement of ovulation, a surrogate measurement for pregnancy risk. Conclusion: Studies evaluating time to pregnancy after last injection of DMPA or NET-EN reported extremely low pregnancy rates during the 2-week interval following the reinjection date; extremely low pregnancy rates for DMPA were also reported for 4 weeks following the reinjection date. Studies of return to ovulation after last injection of DMPA generally found that the earliest ovulation did not occur until several months after the last injection while studies of NET-EN reported ovulations around (or even before) the time for reinjection.
Joachim Höchel - One of the best experts on this subject based on the ideXlab platform.
-
In Vivo Formation of Ethinylestradiol After Intramuscular Administration of Norethisterone Enantate.
Journal of clinical pharmacology, 2018Co-Authors: Christian Friedrich, Matthias Berse, Stefan Klein, Beate Rohde, Joachim HöchelAbstract:It is known that a small fraction of orally administered Norethisterone is metabolically converted to ethinylestradiol. This exploratory, open-label, nonrandomized study was conducted to investigate the systemic exposure to ethinylestradiol after intramuscular administration of Norethisterone Enantate in comparison with the exposure to ethinylestradiol after administration of a standard combined oral contraceptive. Sixteen healthy premenopausal women received an oral contraceptive (ethinylestradiol 30 μg/levonorgestrel 150 μg) once daily for 21 days and-after a 1-week washout period-a single intramuscular dose of 200 mg Norethisterone Enantate. Blood samples to determine ethinylestradiol in serum were taken over 24 hours after the last dose of ethinylestradiol/levonorgestrel and over 8 weeks after administration of Norethisterone Enantate. Oral equivalent doses of ethinylestradiol were estimated based on area under the concentration-time curves. The ethinylestradiol serum concentrations observed after administration of Norethisterone Enantate were relatively low: The mean maximum concentration was only 32% of the maximum observed after ethinylestradiol/levonorgestrel (90% confidence interval, 22.5%-44.7%). The maximum oral equivalent dose of ethinylestradiol was markedly lower than 30 μg ethinylestradiol per day (20.3 μg/day; 90% confidence interval, 14.8-28.0 μg/day). The same applied to the average oral equivalent dose of ethinylestradiol for the 8-week postdose interval (4.41 μg/day; 90% confidence interval, 3.57-5.46 μg/day). To conclude, the study results indicate that metabolic conversion of Norethisterone to ethinylestradiol also occurs after intramuscular administration of 200 mg Norethisterone Enantate, but is associated with a lower exposure to ethinylestradiol than the use of a combined oral contraceptive containing 30 μg ethinylestradiol (plus 150 μg levonorgestrel).
Gregorio Pérez-palacios - One of the best experts on this subject based on the ideXlab platform.
-
Long-acting hormonal contraceptives for women.
The Journal of steroid biochemistry and molecular biology, 1991Co-Authors: J. Garza-flores, P.e. Hall, Gregorio Pérez-palaciosAbstract:Abstract Following the development and widespread use of oral hormonal contraceptives, it became evident that alternative long-acting delivery systems would be required to improve contraceptive practice in some cultural settings where injectable or subdermal routes of administration are preferred. Nowadays, long-acting contraceptives constitute an important option in family planning services in many parts of the world. Indeed, two long-acting injectable contraceptives containing just a synthetic progestogen (depot-medroxyprogesterone acetate (DMPA) and Norethisterone Enantate (NET-EN)) have been in clinical practice for more than 20 years. The World Health Organization's (WHO) Special Programme of Research in Human Reproduction, in collaboration with the U.S. National Institute of Child Health and Human Development (NICHD) and universities primarily in developing countries undertook a synthesis programme aimed at producing an improved injectable preparation by developing new derivatives of known steroids. One such compound (levonorgestrel 17-butanoate) is now at the stage of Phase II clinical testing. In addition, the Special Programme has developed and improved once-a-month injectable formulations and assessed their safety and efficacy in diferent countries worldwide. After large scale clinical testing, at least two prgestogen-estrogen combinations have reached the point of introductory trials.
Christian Friedrich - One of the best experts on this subject based on the ideXlab platform.
-
In Vivo Formation of Ethinylestradiol After Intramuscular Administration of Norethisterone Enantate.
Journal of clinical pharmacology, 2018Co-Authors: Christian Friedrich, Matthias Berse, Stefan Klein, Beate Rohde, Joachim HöchelAbstract:It is known that a small fraction of orally administered Norethisterone is metabolically converted to ethinylestradiol. This exploratory, open-label, nonrandomized study was conducted to investigate the systemic exposure to ethinylestradiol after intramuscular administration of Norethisterone Enantate in comparison with the exposure to ethinylestradiol after administration of a standard combined oral contraceptive. Sixteen healthy premenopausal women received an oral contraceptive (ethinylestradiol 30 μg/levonorgestrel 150 μg) once daily for 21 days and-after a 1-week washout period-a single intramuscular dose of 200 mg Norethisterone Enantate. Blood samples to determine ethinylestradiol in serum were taken over 24 hours after the last dose of ethinylestradiol/levonorgestrel and over 8 weeks after administration of Norethisterone Enantate. Oral equivalent doses of ethinylestradiol were estimated based on area under the concentration-time curves. The ethinylestradiol serum concentrations observed after administration of Norethisterone Enantate were relatively low: The mean maximum concentration was only 32% of the maximum observed after ethinylestradiol/levonorgestrel (90% confidence interval, 22.5%-44.7%). The maximum oral equivalent dose of ethinylestradiol was markedly lower than 30 μg ethinylestradiol per day (20.3 μg/day; 90% confidence interval, 14.8-28.0 μg/day). The same applied to the average oral equivalent dose of ethinylestradiol for the 8-week postdose interval (4.41 μg/day; 90% confidence interval, 3.57-5.46 μg/day). To conclude, the study results indicate that metabolic conversion of Norethisterone to ethinylestradiol also occurs after intramuscular administration of 200 mg Norethisterone Enantate, but is associated with a lower exposure to ethinylestradiol than the use of a combined oral contraceptive containing 30 μg ethinylestradiol (plus 150 μg levonorgestrel).
