Testing usually starts with a detailed history and examination, then hormone blood tests, an ultrasound of the uterus and ovaries, a check that the fallopian tubes are open, and a semen analysis for the male partner. The results guide which treatment, if any, is most suitable.

For women who ovulate irregularly or not at all, for example with PCOS, tablets or injections are used to encourage an egg to mature and be released. Follicle growth is followed by ultrasound to time intercourse or insemination and to keep treatment safe.

The semen sample is washed and concentrated in the lab, then placed into the uterus with a thin, soft catheter at the time of ovulation. It is a simple, quick procedure and is often combined with ovulation medication. It requires at least one open fallopian tube.

After hormone injections to stimulate the ovaries, eggs are collected in a short procedure and fertilized with sperm in the laboratory. The resulting embryos are grown for a few days, and one is transferred into the uterus. Suitable extra embryos can be frozen for later use.

Intracytoplasmic sperm injection is a form of IVF in which an embryologist injects one sperm directly into each mature egg. It is mainly used when sperm count or movement is low, or when fertilization did not happen in a previous IVF cycle.

Eggs or embryos can be frozen using vitrification, a rapid-freezing method that protects them during storage. This can be used to keep extra embryos from an IVF cycle, or to preserve fertility before medical treatments such as chemotherapy.

Male factors are involved in a large share of couples' fertility problems. A semen analysis checks sperm count, movement and shape; depending on the results, further tests, lifestyle advice, medical treatment, IUI or ICSI may be recommended.