S ubfertility affects 1 in 6 couples in the UK. In the initial GP consultation it is helpful to see both partners together, although this may be difficult in a single 10 minute consultation. In 39% of couples, both male and female factors are responsible for subfertility, with male factors accounting for 30% of subfertility problems. Although this article will focus on female factors, male assessment is important, and a semen sample is one of the first steps in an assessment. If an abnormality is detected in the semen analysis, the test is normally repeated and if confirmed a secondary care referral is required. In 70% of cases a female factor will be the primary cause, and this article will focus on female factors in the more detailed management of subfertility. The GP curriculum and female infertility Clinical module 3.08; Sexual health states that:. General practice has an important role in the management of sexual health problems. A holistic and integrated approach should be taken. Sensitive, non-judgemental communication skills are essential Background and definition Subfertility is defined as the inability of a couple to conceive after 12 months of regular vaginal sexual intercourse (two to three times per week). It may be primary subfertility, where the female partner has never conceived, or secondary subfertility, when the female partner has conceived in the past regardless of the outcome of the pregnancy. Recurrent miscarriage is not discussed in this article, but advice can be found in the Royal College of Obstetricians and Gynaecologists (RCOG) Green top guideline no. 17 (RCOG, 2011). Fertility can be assessed in terms of fecundity, which is the conception rate per menstrual cycle. Female age is an important factor in fertility. Fecundity declines with advancing maternal age: in 19 to 26year-old females the probability of fecundity is 92%, whereas in 35 to 39-year-old females it is 80% after a year of regular intercourse (Dunson, Baird, & Colombo, 2004). Couples should be counselled that 84% of women with a regular menstrual cycle having regular vaginal sexual intercourse will conceive within 12 months, 92% within 2 years and 93% within 3 years (Te Velde, Eikemans, & Habbema, 2000). On this basis, simple reassurance and support may be all that is needed for a young woman with a normal menstrual cycle presenting less than a year after starting to try to conceive. Conversely, a 36-year-old woman or young woman with known risk factors for subfertility will need more prompt investigation and secondary referral (Cutting, Morroll, Roberts, Pickering, & Rutherford, 2008). Female subfertility is broadly divided into anovulation problems (inability to release an egg), tubal factors, and uterine and peritoneal factors (endometriosis, adenomyosis and fibroids). Anovulation contributes to 25% of cases and the most common cause is polycystic ovarian syndrome (PCOS) (National Institute for Health and Care Excellence (NICE), 2016; Thonneau et al., 1991). Tubal factors are responsible for 20% of cases (pelvic inflamma...