Zero
recommended alcohol during IVF cycles
200 mg
maximum daily caffeine during conception attempts
60%
iron absorption reduction from coffee with meals
90 days
window where alcohol affects oocyte quality
Dose-Response Data
Alcohol & Conception Rates
Based on prospective cohort studies tracking monthly fecundity rates by alcohol intake.
Zero
Baseline
Recommended during active conception attempts and IVF cycles
1–2 drinks/week
+13% reduced conception per cycle
Even low intake measurably reduces monthly fecundity
3–6 drinks/week
+26% reduced conception per cycle
Disrupts LH surge timing and luteal phase progesterone
7+ drinks/week
+60% reduced conception per cycle
Associated with anovulation, cycle irregularity, and early pregnancy loss
Dose-Response Data
Caffeine & Fertility Risk
0–100 mg/day
No measurable impact
Roughly 1 small espresso or 1 cup filter coffee
100–200 mg/day
Minimal — within safe range
1–2 cups filter coffee; stay below 200 mg during conception attempts
200–300 mg/day
Borderline — caution in IVF
Associated with reduced IVF success rates in some studies
300+ mg/day
+40% increased miscarriage risk
Consistent association with early pregnancy loss across multiple cohort studies
Caffeine Content Reference
Espresso (single shot)60–80 mg
Filter coffee (250 ml)80–120 mg
Instant coffee (250 ml)60–80 mg
Green tea (250 ml)30–50 mg
Black tea (250 ml)40–70 mg
Matcha (1 tsp)50–70 mg
Dark chocolate (30 g)20–30 mg
Cola (375 ml can)35–45 mg
Energy drink (250 ml)80–160 mg
The Mechanisms
Why both substances affect fertility at the cellular level.
How Alcohol Affects Fertility
- →Alcohol disrupts the hypothalamic-pituitary-ovarian axis by suppressing gonadotropin-releasing hormone (GnRH) pulsatility. Even moderate intake (3–6 drinks/week) measurably reduces luteinising hormone (LH) surge amplitude and delays ovulation.
- →Ethanol is directly toxic to oocytes — it impairs spindle assembly during meiosis, increasing the risk of chromosomal errors (aneuploidy). This is particularly relevant in the 90-day window before egg retrieval or natural conception.
- →Alcohol depletes zinc, B6, folate, and magnesium — all critical for oocyte maturation, DNA methylation, and early embryo development. A single episode of heavy drinking can deplete zinc levels for up to 72 hours.
- →In the luteal phase, alcohol reduces progesterone production by impairing corpus luteum function. Low luteal progesterone is directly associated with implantation failure and early pregnancy loss.
How Caffeine Affects Fertility
- →Caffeine is a methylxanthine that crosses the placenta and reaches the developing embryo within minutes of consumption. The embryo lacks the liver enzymes (CYP1A2) to metabolise caffeine — so embryonic exposure is prolonged relative to maternal exposure.
- →High caffeine intake (>300 mg/day) is associated with a 40–60% increased risk of miscarriage across multiple large cohort studies. The mechanism involves impaired trophoblast invasion and reduced uterine blood flow via caffeine's vasoconstrictive effects.
- →Caffeine elevates cortisol and adrenaline, activating the HPA axis. Chronic HPA axis activation suppresses gonadotropin-releasing hormone (GnRH) pulsatility and reduces progesterone production — the same pathway as psychological stress.
- →Caffeine impairs iron absorption when consumed within 1 hour of meals — a significant concern for fertility patients already at risk of low ferritin. Coffee reduces iron absorption by up to 60%; tea by up to 70%.
Your Action Plan
Practical Steps
0/15 completed
Alcohol
Aim for zero alcohol during active conception attempts and IVF cycles
If reducing gradually, set a clear date to stop — 90 days before retrieval or conception attempt
Replace evening wine with sparkling water + citrus, kombucha, or alcohol-free alternatives
Inform your partner — paternal alcohol intake also affects sperm DNA integrity
Be aware that 'low alcohol' wines can still contain 5–7% ABV — read labels
Caffeine
Stay below 200 mg caffeine/day during conception attempts
Reduce to <100 mg/day during IVF stimulation and the two-week wait
Avoid coffee within 1 hour of iron-rich meals or iron supplements
Switch afternoon coffee to green tea or matcha (lower caffeine, higher antioxidants)
Avoid energy drinks entirely — high caffeine plus additives with no fertility benefit
Decaf coffee is safe — the residual caffeine is <5 mg per cup
Nutrient Repletion After Alcohol Reduction
Increase zinc-rich foods: oysters, pumpkin seeds, red meat, legumes
Ensure adequate folate/methylfolate — alcohol depletes folate rapidly
Add B6-rich foods: salmon, chicken, bananas, sunflower seeds
Supplement magnesium glycinate 300–400 mg/day — alcohol is a potent magnesium depleter