PURPOSE: to evaluate the luteal function in adolescents with regular menstrual cycles. METHODS: this prospective cohort study included 55 adolescents, aged 14-19 years, with menarche at 12.2 years. Ovulation was identified by ultrasound, starting on the second or fifth day of the cycle. The corpus luteum vascularization and the resistence index of the ovarian vessels were measured by Doppler on the tenth postovulatory day. Progesterone was measured by chemoluminescence on days 6, 9 and 12 of the luteal phase. The endometrial biopsy was performed 8 to 10 days after ovulation. The results were analyzed using the SPSS software and were considered significant when p<0.05. RESULTS: on average ovulation was on day 17. Progesterone levels were 11.4, 10.9 and 3.9 ng/mL on days 6, 9, and 12 after ovulation, respectively; the progesterone mean during the whole luteal phase was 10.3 ng/ml. Luteal vascularization was scarce in 34.6%, mild in 23.6% and exuberant in 41.8%. The resistance index was 0.441. On the tenth day post-ovulation the endometrium was normal in 85.5% and out-of-phase in 14.5%. There was no correlation between the ovulation day and endometrial dating (p=0.294), levels of progesterone and endometrial dating (p=0.454), progesterone and corpus luteum vascularization (p=0.994), or resistance index (p=0.237). There also was no association between endometrium development and degree of vascularization (p=0.611). CONCLUSION: abnormal luteal function in adolescents with regular menstrual cycles was found in 14.5%. Degree of vascularization, resistance index, and serum progesterone were not related to endometrium development.
Lutheal fase; Menstrual cycle; Adolescent; Retrospective studies; Cohort studies
