The period before conception matters more than most people realise. Eggs take 90 days to complete their final growth phase. Sperm take 70–74 days to develop. What you eat, how you exercise, what you’re exposed to, and which supplements you take in the 3 months before conception directly influences the quality of the reproductive cells that will create the pregnancy.
Essential Preconception Nutrients for Women
Folic acid (400mcg daily, starting at least 4 weeks before conception) — the NHS recommendation is unambiguous. Folic acid reduces neural tube defect risk (spina bifida, anencephaly). The neural tube closes at day 28 of pregnancy — before most women know they are pregnant — making pre-conception supplementation essential. High-risk women (previous NTD pregnancy, epilepsy medication, BMI over 30, diabetes) require 5mg prescription-dose folic acid — discuss with your GP. Vitamin D (10–25mcg daily) — supports uterine implantation, immune tolerance of the embryo and placental development. Associated with reduced miscarriage risk. DHA omega-3 (200–300mg daily) — critical for baby’s brain and retinal development from the earliest stages. Start before conception rather than waiting for pregnancy confirmation. Iodine (150mcg daily) — essential for fetal thyroid hormone production and brain development. Commonly insufficient in UK women who avoid dairy and fish; often not in standard folic acid supplements. Iron — correct any iron deficiency before conception. Anaemia at conception increases complication risk throughout pregnancy.
Preconception Supplements for Men
Male factor infertility accounts for 40–50% of cases — yet men rarely receive preconception guidance. Zinc (15–25mg daily) — essential for sperm production, morphology and motility. Deficiency measurably impairs sperm quality. Selenium (55–100mcg daily) — required for the selenoprotein enzyme protecting sperm from oxidative damage. UK soils are selenium-depleted. Coenzyme Q10 (200–600mg daily) — powers sperm motility through ATP production in the mitochondrial mid-piece. Multiple RCTs show significant improvements in sperm motility and morphology. Vitamin C (500mg–1g daily) — antioxidant protection of sperm DNA integrity during the journey through the female reproductive tract. Lycopene (6–8mg daily) — has strong evidence for improving sperm concentration and motility. Vitamin D — deficiency associated with reduced sperm motility and morphology.
Lifestyle for Fertility
Weight — both underweight and overweight significantly impair fertility in women and men. A healthy BMI optimises hormonal environment. Smoking — accelerates egg depletion, damages sperm DNA, significantly increases miscarriage risk. Stop as early as possible before trying to conceive. Alcohol — no safe level in pregnancy is established. Reduce to zero. Heavy alcohol use impairs both male and female fertility. Heat for men — spermatogenesis requires 2–3°C below core temperature. Regular hot baths, saunas, laptop on lap and tight underwear all temporarily reduce sperm quality. These changes reverse within 90 days of modification.
Frequently Asked Questions About Preconception Health
How far in advance should I start preconception supplements?
Ideally 3 months before actively trying — to optimise egg quality (90-day cycle), sperm quality (70-day cycle) and to build adequate body stores of critical nutrients. The minimum for folic acid is 4 weeks. For Vitamin D, starting at any point is beneficial. Men should start CoQ10 and other sperm-supporting supplements ideally 3 months before planned conception.
We’ve been trying for 6 months without success — should we see a GP?
The NHS defines infertility as failure to conceive after 12 months of regular unprotected sex. However: if you’re over 35, seek assessment at 6 months. If either partner has a known fertility-affecting condition (PCOS, endometriosis, previous STI, undescended testis), seek earlier assessment. Initial investigations are straightforward — ovarian reserve blood tests, progesterone to confirm ovulation, and semen analysis. These can all be arranged through your GP.
Does stress cause infertility?
Chronic severe stress does modestly affect fertility — cortisol suppresses GnRH and can cause cycle irregularity. However, the magnitude of this effect is considerably smaller than physical causes of infertility. Many people conceive normally while experiencing significant life stress. Managing stress (exercise, sleep, support) is a valid goal but “just relax” is unhelpful advice and can be harmful to couples struggling with fertility.
Can a man’s diet affect sperm quality?
Yes — significantly. A Mediterranean diet is associated with higher sperm concentration, motility and morphology. High processed meat, alcohol and saturated fat intake are associated with poorer sperm parameters. The most impactful individual changes for sperm quality: stop smoking, reduce alcohol, increase antioxidant-rich food (berries, vegetables, tomatoes for lycopene), and supplement CoQ10, Vitamin C, zinc and selenium.
Browse preconception vitamins at Huncoat Pharmacy. Related: PCOS Guide, Postpartum Recovery.