Purpose. Our purpose was to establish an evaluation system for oocyte quali
ty based on the incidence of cumulus cells apoptosis and to examine the eff
ect of coculture, using autologous cumulus cells, on the outcome of IVF-ET
according to proliferative activities of helper cells and the incidence of
cumulus cells apoptosis.
Methods. Cumulus cell masses were collected from 91 mature oocytes among 33
0 oocytes retrieved fi-om a total of 34 IVF-ET cycles with tubal infertilit
y and unexplained infertility. The incidence of apoptosis in cumulus cells
was assessed by apoptosis detection kit fluorescein. On ovum pick tip, 2nd
day embryos were cocultured with autologous cumulus cells. Prior to cocultu
re, in vitro proliferative activity of cumulus cells was evaluated.
Results. Cumulus cells from patient groups over 40 years old had a signific
antly increased apoptosis incidence, a lower fertilization rate, and the de
creased number of oocytes retrieved compared to the other age groups (P < .
05). The incidence of cumulus cells apoptosis was significantly lower when
the number of oocytes retrieved was 5 or less (P < .05). Cumulus cells from
fertilized oocytes (0.43 +/- 0.07%) and those from patients who became pre
gnant (0.44 +/- 0.11%) following IVF-ET showed a significantly lower incide
nce of apoptosis compared to those of unfertilized oocytes (1.80 +/- 0.35%;
, P < .001) and the nonpregnant group (0.81 +/- 0.10%; P < .05). Embryo qua
lity also had a negative correlation with the incidence of cumulus cells ap
optosis. Coculture of fertilized oocytes with cumulus cells with high proli
ferative activity resulted in improved rates of implantation and pregnancy
compared to that with poor active cumulus cells. No significant difference
was found between the in vitro proliferative activity of cumulus cells and
the incidence of cumulus cells apoptosis (P < .063).
Conclusions: The age of women might influence the incidence of apoptosis in
cumulus cells, and the increased incidence of apoptosis is associated with
the number of oocytes retrieved, the fertilization rate, and the pregnancy
outcome following IVF-ET These results suggest that the incidence of cumul
us cells apoptosis can be used in predicting oocyte quality., outcome of IV
F-ET, and age-related decline in fertility.