Assessment of the quality of cervical mucus among users of the levonorgestrel-releasing intrauterine system at different times of use.
OBJECTIVE
The quality of cervical mucus (CM) among the levonorgestrel-releasing intrauterine system (LNG-IUS) users is controversial. The objectives were to assess CM compared to the levels of oestradiol (E2) and the frequency of cycles with luteal activity among users of the LNG-IUS.


METHODS
In total, 224 LNG-IUS users for between two months and five years were recruited at a Brazilian family planning clinic. For the cross-sectional part of the study, we enrolled 175 LNG-IUS users at 2, 6 12, 24, 36, 48, and 60 months after insertion (25 women in each group), and we performed one evaluation. For the prospective part of the study, we enrolled 49 LNG-IUS users at the same lengths of use after insertion (7 women in each group), and we evaluated these women once a week for five consecutive weeks. .


RESULTS
Mean (± SEM) CM scores of all evaluations among women with single and weekly evaluations were between 3.3 ± 0.9 and 8.5 ± 0.3, respectively independently of the length of use of the LNG-IUS. Mean E2 values ranged from 45.5 ± 6.8 to 472.5 ± 34.7 pg/ml and the maximum ovarian follicle diameter on the days of evaluation varied from 14.0 ± 1.3 to 31.2 ± 0.4 mm.


CONCLUSIONS
The mean CM score of all evaluations, independent of the length of use of the LNG-IUS and normal levels of serum E2, was below 10 was according to the WHO is inadequate for sperm penetration.
a Family Planning Clinic, Department of Obstetrics and Gynaecology , University of Campinas Medical School , Campinas , Brazil.
Leticia G
LG
Moraes
a Family Planning Clinic, Department of Obstetrics and Gynaecology , University of Campinas Medical School , Campinas , Brazil.
Nadia M
NM
Marchi
a Family Planning Clinic, Department of Obstetrics and Gynaecology , University of Campinas Medical School , Campinas , Brazil.
Ana C
AC
Pitoli
a Family Planning Clinic, Department of Obstetrics and Gynaecology , University of Campinas Medical School , Campinas , Brazil.
Maria M
MM
Hidalgo
a Family Planning Clinic, Department of Obstetrics and Gynaecology , University of Campinas Medical School , Campinas , Brazil.
Carolina
C
Silveira
a Family Planning Clinic, Department of Obstetrics and Gynaecology , University of Campinas Medical School , Campinas , Brazil.
Waleska
W
Modesto
a Family Planning Clinic, Department of Obstetrics and Gynaecology , University of Campinas Medical School , Campinas , Brazil.
Luis
L
Bahamondes
D000328:Adult; D001938:Brazil; D002582:Cervix Mucus / Q000502:physiology*; D003271:Contraceptive Agents, Female / Q000008:administration & dosage* / Q000097:blood; D003430:Cross-Sectional Studies; D004958:Estradiol / Q000097:blood; D005260:Female; D006801:Humans; D007436:Intrauterine Devices, Medicated; D016912:Levonorgestrel / Q000008:administration & dosage* / Q000097:blood; D006080:Ovarian Follicle / Q000502:physiology; D011446:Prospective Studies; D013997:Time Factors
D003271:Contraceptive Agents, Female; D004958:Estradiol; D016912:Levonorgestrel
Cervical mucus; levonorgestrel-releasing intrauterine system; ovulation