In a woman's menstrual cycle several Ovums begin to mature but usually only one becomes fully mature. It is possible to donate this one mature Ovum, but to increase the success of Ovum donation, clinics prefer to give Ovum donors drugs so that more Ovums mature.
Ovum development is usually monitored by ultrasound scanning which enables a picture of the ovaries containing the Ovums to appear on a television screen. Hormone levels in the blood may be measured at the same time.
• Using a needle guided by ultrasound. This may be done under a general anaesthetic or more usually a sedative ('conscious sedation'). A fine hollow needle is passed either through the bladder, urethra or vagina and each Ovum is removed in turn. If the ovaries are abnormally situated it may sometimes be necessary to pass a needle under ultrasound guidance through the abdominal wall.
• Laparoscopy, for which a general anaesthetic is normally necessary. A small cut is made just below the navel for a laparoscope (an instrument for looking into the abdomen) to be inserted and a fine, hollow needle is inserted separately to remove the Ovums.
Some women undergoing sterilisation decide to donate Ovums. Since laparoscopy is frequently used to perform sterilisation, no additional operative procedures will be required to donate Ovums.
• Suppression of the normal menstrual cycle by a nasal spray or an injection given every day throughout the 28 day cycle.
• Stimulation of the growth and maturation of the Ovums using daily injections or tablets. The injections contain the hormone that naturally causes Ovum production in the ovaries. These drugs are known as superovulatory drugs.
When the ultrasound scanning and/or hormone measurements show that an adequate number of Ovums are maturing, a final hormone injection is given which completes the maturing process. This injection must be carefully timed 34-38 hours before Ovum collection.
Some of these drugs can be taken by mouth but most have to be given by injection. Usually you can be taught to do these yourself at home.
Whilst taking the first drug, some women experience mild side-effects. These may include hot flushes, feelings of depression and irritability, headaches and sleeplessness. These side-effects usually disappear once the second drugs begin and they are not a cause for concern.
Before the final hormone injection there will be an ultrasound scan to see how many Ovums are developing on the ovaries. At this stage it may be clear that a woman has over-responded to the drugs and too many Ovums have been produced. The woman may feel bloated and have abdominal pain. To avoid the development of more serious side-effects, known as Ovarian Hyperstimulation Syndrome, the final hormone injection and Ovum collection may have to be cancelled. If the cycle is abandoned at this stage, ovarian hyperstimulation is avoided.
Despite careful monitoring, a small number of women may develop a mild or moderate form of the syndrome. Cysts may appear on the ovaries and fluid may collect in the abdominal cavity, causing abdominal discomfort. This condition needs to be monitored by a fertility specialist. It is usually treated by bed rest, drinking plenty of fluids and taking simple painkillers.
Very rarely (in about 1% of cases) the response to the superovulatory drugs is excessive and a large number of Ovums develop causing the ovaries to swell. Side-effects such as nausea and vomiting, abdominal pain and swelling, and shortness of breath occur. A patient may also feel weak and faint and notice a reduction in urine output. These serious complications require urgent hospital treatment to restore the fluid balance and monitor progress.
Women undergoing ultrasound-directed Ovum recovery may notice a small amount of blood in their urine or from their vagina for a day afterwards. This is quite common and should not cause concern.
Laparoscopy carries the usual minor risks and side-effects of any procedure involving a general anaesthetic. Some women experience soreness in the stomach, chest or shoulders, or vaginal bleeding for a few days after the operation.
Following laparoscopy there may be some abdominal pain similar to a painful period. The pain usually disappears in a short time. The operation to remove Ovums under ultrasound can be uncomfortable and painkilling drugs can be given before the procedure. Some abdominal discomfort may be experienced for a short time after the operation is over.