Effect of levonorgestrel-releasing intrauterine device on hormonal profile and menstrual pattern after long-term use.
In the present study 14 women after 6 years' use of levonorgestrel-releasing IUD were investigated for the changes of LH, progesterone (P), estradiol (E2), prolactin (PRL) and serum binding globulin (SHBG) in relation to the levonorgestrel levels throughout a segment of 26-40 days with the aim of comparing the hormonal profiles with those during the first year of use of Lng-IUD. Ultrasound scanning was used to follow the development of follicles along with the RIA measurement of hormones. The results of serum LH, P and E2 showed ovulation in 11 cases with either normal menstrual cycles (5 cases), prolonged or irregular cycles (4 cases) or with amenorrhea for 2-3 years (2 cases). One case showed insufficiency of luteal function and 2 cases showed anovulation but with follicular hyperactivity. Higher percentages of ovulatory cycles (78.5%) were found after 6 years of use. No case of complete suppression of ovulation was found. Anovulatory cycles only constituted 14.3%. Clinically, the development of follicles followed by ultrasound scanning further confirmed the hormonal findings. The persistent enlargement of follicles coincided with high levels of E2. After 6 years of use, the serum levels of levonorgestrel were still maintained at mean levels of 314.26 pmol/L and 470.63 pmol/L in the ovulatory and anovulatory groups, respectively. It is concluded that over two-thirds of the cases have ovulatory cycles after long-term use of Lng-IUD; the contraceptive effect is mainly due to its local action on the endometrium, with much less effect on the ovarian function.
Xiao
B
B
National Research Institute for Family Planning, WHO Collaborating Centre for Research in Human Reproduction, Haidian District, Beijing, People's Republic of China.
Zeng
T
T
Wu
S
S
Sun
H
H
Xiao
N
N
D000328:Adult; D003271:Contraceptive Agents, Female / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004967:Estrogens / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007436:Intrauterine Devices, Medicated / Q000592:standards*; D016912:Levonorgestrel / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D007986:Luteinizing Hormone / Q000097:blood*; D008597:Menstrual Cycle / Q000187:drug effects* / Q000502:physiology; D006080:Ovarian Follicle / Q000000981:diagnostic imaging / Q000187:drug effects / Q000502:physiology; D010053:Ovary / Q000187:drug effects / Q000502:physiology; D011374:Progesterone / Q000097:blood; D011388:Prolactin / Q000097:blood; D011863:Radioimmunoassay; D012738:Sex Hormone-Binding Globulin / Q000032:analysis; D013997:Time Factors; D014463:Ultrasonography
D003271:Contraceptive Agents, Female; D004967:Estrogens; D012738:Sex Hormone-Binding Globulin; D011374:Progesterone; D016912:Levonorgestrel; D011388:Prolactin; D007986:Luteinizing Hormone