Infertility is estimated to affect around one in seven heterosexual couples in the UK. There are many causes – ovulatory disorders, tubal damage, sperm problems, uterine or peritoneal issues, pelvic conditions such as endometriosis, gamete or embryo defects – but in around a quarter of cases, the origin is never identified.
Appropriate investigations (for example, ovulation testing, uterine and tubal checks, semen analysis and screening for infections) are key in determining whether treatment should be medical or surgical to restore fertility, or if assisted reproductive techniques (ART) are the next step.
Availability of and eligibility for NHS fertility treatment varies across the UK. Anyone looking to privately fund treatments should be encouraged to choose a clinic licensed by the Human Fertilisation and Embryology Authority (HFEA).
Fertility drugs may be all that is needed, or may be combined with ART as detailed below.
The main medicines used are typically as follows:
• Ovulatory stimulants such as clomifene, metformin, gonadotrophins (e.g. cetrorelix) and dopamine agonists (e.g. cabergoline)
• Gonadorelin analogues such as nafarelin may be used to suppress the normal menstrual cycle before ovulatory stimulants are used
• Gonadotrophins may be prescribed to men to stimulate sperm production.
Intrauterine insemination (IUI) involves inserting selected sperm from a previously gathered sample into the uterus, sometimes after the woman has undergone ovarian stimulation. It may be the most appropriate technique for couples who can’t have vaginal sex, perhaps because of a physical disability, or if unprotected sex is inadvisable; for example, because one partner has HIV.
In vitro fertilisation (IVF) starts with the woman medically suppressing her normal menstrual cycle, before undergoing ovarian stimulation. Eggs are removed and fertilised with selected sperm in a laboratory, then one or two of the resulting embryos are returned to the uterus to hopefully implant and develop as in a naturally conceived pregnancy.
Surgical sperm extraction may be performed on men who have little or no sperm in their semen, maybe because of a vasectomy, cancer treatment or previous infection, or who cannot ejaculate.
Intracytoplasmic sperm injection (ICSI) is an option if infertility is sperm-related, as it consists of injecting the sperm directly into the egg before the resulting embryo is returned to the uterus.
Egg and/or sperm donation is sometimes used if one partner has been identified as having a problem that is making conception unlikely. Donated sperm is used from IUI and donated eggs via IVF. Since 2005, anyone who has registered to donate eggs or sperm is required to provide information about their identity, as any children born as a result has a legal entitlement to know their parentage when they turn 18 years of age.
Pointers to bear in mind when dealing with patients undergoing fertility treatment:
• Thanks to Mona Koshkouei, clinical standards manager at McKesson UK, for her help in putting together this article.
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