n some cases the cause of infertility can be treated and subsequently overcome, which would allow the couple to achieve natural conception, i.e. without the help of assisted reproductive technologies (ARTs) such as in-vitro fertilization – IVF or intracytoplasmic sperm injection – ICSI. However, if achieving natural conception is highly unlikely or if the couple chooses assisted conception, in most cases the female partner

would have to undergo hormonal stimulation of the ovaries (controlled ovarian hyperstimulation (COH)).

If COH is not undertaken, the assisted reproductive procedure relies on natural ovulation, which only contributes 1 to 2 mature egg cells. With hormonal stimulation that number can be increased more than tenfold.

If the female patient has an irregular cycle, she is given oral contraceptives for about a month in order to regulate her menstrual cycle, which would allow the time of fertility drug administration to be accurately determined.

Controlled ovarian hyperstimulation is a process whereby fertility drugs are continuously administered over a period of time, whose length is dependent on the stimulation protocol being used. Once the female patient starts taking the drugs, her doctor will start monitoring the growth of her follicles by regular ultrasound and blood tests.

Retrieving good-quality oocytes is a prerequisite for having good-quality embryos. That is why selecting the most suitable COH protocol is very important. It is selected based on factors like the patient’s age, fertility history and ovarian reserve (egg supply).