Cheng J, Weng L, Han X
Department of Obstetrics and Gynecology, Chaoyang Hospital, Affiliated to Capital University of Medical Science, Beijing 100020, China.
Zhonghua Fu Chan Ke Za Zhi. 2001 Jul;36(7):424-7.
To study whether weekly low dose of mifepristone (5 mg or 10 mg) is sufficient to prevent pregnancy.
Thirty-nine women were randomly allocated to take mifepristone 5 mg (group A) or 10 mg (group B) doses once weekly starting on cycle day 2-3. The serum levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH) were determined by enzymeimmunoassay (EIA), and estradiol (E2) and progesterone (P) levels by radioimmunassay (RIA). Serum mifepristone concentrations were measured by high performance liquid chromatography (HPLC). Morphometric analyses and progesterone receptor (PR), Dolichus biflorus agglutinin (DBA-lectin) and integrin alpha v beta 3 of endometrium were also measured.
There were 4 pregnancies out of 64 cycles in group A, and 3 out of 68 cycles in group B. Normal LH and FSH peak could be detected in the first treatment cycles, LH peak appeared on 15-17 d. The concentrations of P were (51.93 +/- 7.91) nmol/lL and (69.00 +/- 21.29) nmol/L in group A and B respectively. The average level of E2 was (407.81 +/- 89.27) pmol/L in group A, and (557.85 +/- 204.69) pmol/L in group B. Serum mifepristone level could be detected within 36 hours. The PR concentration in endometrium decreased significantly, but not of DBA-lectin, integrin alpha v beta 3.
Administration of mifepristone 5 mg or 10 mg once weekly does not inhibit ovulation completely. The follicular phase prolonged slightly, and E2 levels were low following treatment. The endometrium showed delayed development. The clinical contraceptive effectiveness needs to be improved.
研究每周低剂量米非司酮（5毫克或10毫克）是否足以预防妊娠。
39名女性被随机分配，从月经周期第2 - 3天开始，每周一次服用5毫克米非司酮（A组）或10毫克米非司酮（B组）。采用酶免疫分析（EIA）测定血清促黄体生成素（LH）和促卵泡生成素（FSH）水平，采用放射免疫分析（RIA）测定雌二醇（E2）和孕酮（P）水平。通过高效液相色谱法（HPLC）测定血清米非司酮浓度。还对子宫内膜进行形态计量分析以及检测孕酮受体（PR）、双花扁豆凝集素（DBA - 凝集素）和整合素αvβ3。
A组64个周期中有4例妊娠，B组68个周期中有3例妊娠。在第一个治疗周期可检测到正常的LH和FSH峰值，LH峰值出现在第15 - 17天。A组和B组的P浓度分别为（51.93±7.91）nmol/L和（69.00±21.29）nmol/L。A组E2平均水平为（407.81±89.27）pmol/L，B组为（557.85±204.69）pmol/L。在36小时内可检测到血清米非司酮水平。子宫内膜中PR浓度显著降低，但DBA - 凝集素、整合素αvβ3浓度未降低。
每周一次服用5毫克或10毫克米非司酮不能完全抑制排卵。卵泡期略有延长，治疗后E2水平较低。子宫内膜显示发育延迟。临床避孕效果有待提高。
