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A. Does she produce oocytes?
In 21% of the couples with fertility problems a disturbed ovulation is the main cause.
The maximum number of oocytes, around 7 million, is present in the female foetus at around 20 weeks before birth. From that moment onwards the continuous loss of oocytes starts (700-1000 a month!). Around birth approximately 1 million oocytes are present hidden in undeveloped follicles. Click here (nr 1 in the figure of the ovary and ovulation)
At the onset of puberty 300,000 oocytes are left and because of the matured hormonal regulation system every month one oocyte will be "rescued" from a pool of 700 that are lost that month. This rescued follicle will further mature and ovulate, releasing the oocyte.
During this maturation the follicle will grow in size and pressure will build up in the follicle. This can be felt as dull pain in the abdomen. Ovulation is the "bursting"of the follicel, releasing the follicular fluid and oocyte in the abdominal cavity. Click here (6 and 7 in the figure of the ovary and ovulation)
If intercourse has occured at the time of ovulation the spermatzoa will swim up the female reproductive tract and meet the oocyte within the abdominal cavity. When the spermatozoa have found the oocyte only one spermatozoa is allowed to enter the oocyte through the outer shell (zona pellucida) after which this barriere is sealed. See figure penetration of spermatozoa.
The picture below on the left shows an oocyte immediately after ovulation. The picture on the right shows an oocyte of which the surrounding cumuluscells are removed. The "egg-shell" or zona pellucida is clearly visible.
 
This picture shows a oocyte at a magnification of 200x:
B. What about oocyte quantity and quality?
See for this The aging ovary (in Dutch)
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