Anovulations in an ovary during two menstrual cycles enhance the pregnancy potential of oocytes matured in that ovary during the following third cycle.
The aim of this study was to test whether ovulation from an ovary affects the health of oocytes from dominant follicles in that ovary two cycles later. A total of 80 women each with two intact ovaries underwent 270 treatment cycles (155 natural cycles and 115 clomiphene citrate cycles) all showing unilateral ovulation. The results from the in-vitro fertilization (IVF) treatment were grouped according to whether ovulation (O) or anovulation (A) (no ovulation) was observed in the ovary with dominant follicle during the treatment cycle in the previous two cycles: O-O, A-O, O-A and A-A (previous second cycle-previous first cycle). The rate of pre-embryo formation in A-A was significantly higher than that of O-A. The pregnancy rate in A-A (29%) was also higher than those of O-A (13%), A-O (9%) and O-O (5%). These rates increased from O-O to A-A as the number of previous ovulations in an ovary decreased. The presence of a corpus luteum and/or a dominant follicle is likely to exert local negative effects on the health of the oocyte contained in the follicle selected to ovulate up to two cycles later. Anovulations in an ovary for two menstrual cycles may therefore provide improved conditions for the development of a healthier oocyte with an increased pregnancy potential.
Fukuda
M
M
Fukuda Ladies Clinic, Hyogo, Japan.
Fukuda
K
K
Yding Andersen
C
C
Byskov
A G
AG
D000328:Adult; D000858:Anovulation / Q000503:physiopathology*; D002996:Clomiphene / Q000627:therapeutic use; D005260:Female; D005300:Fertility Agents, Female / Q000627:therapeutic use; D005306:Fertilization; D005307:Fertilization in Vitro; D006801:Humans; D008597:Menstrual Cycle / Q000502:physiology*; D009865:Oocytes / Q000502:physiology*; D010053:Ovary / Q000503:physiopathology*; D011247:Pregnancy / Q000502:physiology*; D018873:Pregnancy Rate; D016896:Treatment Outcome
D005300:Fertility Agents, Female; D002996:Clomiphene