Advising couples on subfertility

Factors causing subfertility, including advice to give couples and when further investigation is required.

Definitions and epidemiology

A woman of reproductive age who has not conceived after 1 year of unprotected vaginal sexual intercourse, in the absence of any known cause of infertility, should be offered further clinical assessment and investigation along with her partner.

GPs should offer an earlier referral for specialist consultation to discuss the options for attempting conception, further assessment and appropriate treatment where:

  • the woman is aged 36 years or over
  • there is a known clinical cause of infertility or a history of predisposing factors for infertility.

Subfertility affects approximately one in six couples in the Western world. Most couples have relative subfertility (a reduced chance of conception) rather than absolute infertility (no chance of conception) due to problems in either, or both, partners.

Increasing female age has a profound negative effect on the likelihood of pregnancy, both with natural conception, and with any fertility treatment options.

Definition of primary and secondary subfertility

Primary subfertility is defined as delay in conception for a couple who have no previous pregnancies.

Secondary subfertility is defined as delay in conception for a couple who have conceived previously, even if pregnancy did not end with a successful outcome (such as a miscarriage or ectopic pregnancy).

Psychological aspects

When couples have fertility problems, both partners should be informed that stress in the male and/or female partner can affect the couple's relationship and is likely to reduce libido and frequency of intercourse which can contribute to the fertility problems. People who experience fertility problems should be informed that they may find it helpful to contact a fertility support group.

Chance of conception

People who are concerned about their fertility should be informed that over 80% of couples in the general population will conceive within 1 year if:

  • the woman is aged under 40 years and
  • they do not use contraception and have regular sexual intercourse.

Of those who do not conceive in the first year, about half will do so in the second year (cumulative pregnancy rate over 90%).

GPs should give the following advice:

  • Stabilise any pre-existing medical condition (such as hypertension, diabetes, epilepsy, thyroid disorder, cardiac problems) in either partner. Review medications and check if medication impacts upon sperm function.
  • Check BMI and advise accordingly – couples should aim for a BMI of 20-30 and gain or lose weight accordingly
  • Advise both partners to stop smoking/use of recreational drugs
  • Women who are trying to become pregnant should be informed that drinking no more than 1 or 2 units of alcohol once or twice per week and avoiding episodes of intoxication reduces the risk of harming a developing fetus
  • Men should be informed that excessive alcohol intake is detrimental to semen quality. Consumption within the recommended amount of 3-4 units per day is unlikely to affect semen quality
  • Advise intercourse 2-3 times per week
  • Advise all women trying to conceive to take folic acid 400 micrograms daily to reduce risk of neural tube defects and for those with diabetes, epilepsy and on anti-epileptic medication to take 5mg daily
  • Screen for rubella, and offer immunisation if non-immune (avoid pregnancy for 1 month after immunisation). Consider screening for HIV, hepatitis B and C in high risk groups

Subfertility can be caused by factors in both men and women, and in 25% cases, remains unexplained even after investigation. In 30% of cases, male factors play a part.

Factors in women can be split into ovulatory problems (25%), tubal problems (20%) and uterine/peritoneal problems (10%). Cases of subfertility can involve factors from both male and female partners.

The tests in table 1 should be organised by primary care before, or while awaiting referral, to secondary care. Local guidance should be consulted for any additional measures, and to ensure referrals are accepted promptly.

Table 1: Tests to conduct





Females with regular cycles


Early follicular phase (day 1–5 of cycle)

Assess ovarian


Mid-luteal phase (adjust to cycle length – 7 days prior to expected menses)

Assess ovulation

Females with irregular cycles or amenorrhoea


With menses or any time in very prolonged cycles

Assess pituitary


Any time

Establish cause of oligomenorrhoea/

All females

Rubella serology

Any time

Confirm immunity

Cervical smear

If due

Ensure up to date

Transvaginal ultrasound scan

If you suspect PCOS or uterine abnormality, such as fibroids

Assess pelvic

All men

Semen analysis ×2

Sample after 2–5 days abstinence. If first sample is abnormal, perform a second sample after 3 months

Assess sperm


Couples who present with subfertility rarely have absolute infertility.

Factors that are contributing to the problem usually cause relative subfertility to a greater or lesser degree, and there may be relevant factors in both partners.

Investigations should follow a systematic protocol designed to identify:

  • problems with ovulation
  • problems with semen
  • tubal or uterine problems.
  • Dr Abdelmageed Abdelrahman, Trainee in obstetrics and gynaecology, Northern Ireland Deanery, United Kingdom

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Further reading

NICE Guidance. Fertility problems: assessment and treatment. 2013

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