The short explanation
They can. Smoking is linked with lower sperm quality in men and with reduced fertility and higher miscarriage risk in women. Heavy drinking can lower sperm quality and hormone levels too. For couples trying, the general advice is for the man to stop smoking and keep alcohol low, and for the woman to avoid both. Stopping helps. Sperm take around three months to develop, so changes made now will show in his sperm over the next few months.
What depends on your situation
The parts of this that change from woman to woman. Uncertainty is stated, not hidden.
- How much difference it makes depends on how much he smokes or drinks, his age, and his semen results. Chewing tobacco and second-hand smoke also matter.
- Many men find it hard to stop. Doctors, government hospital tobacco cessation clinics and the national quitline can help, and support makes quitting more likely to succeed.
- Your own weight, smoking and alcohol use also affect fertility, so it often helps to make changes together rather than as blame.
What this answer cannot determine
The boundary of online education. These need a clinician who can see you.
- This answer cannot say whether his habits are causing any delay. A semen analysis and both partners' history are needed.
Questions for your clinician
Take these with you. You can add any of them to an appointment card.
- Could his smoking or drinking be affecting our chances?
- Should he have a semen test?
- What support is there to help him stop smoking?
- Are there other lifestyle changes we should both make?
When to seek help
Clinician-approved guidance for this topic. When in doubt, being seen is never the wrong choice.
Book an appointment soon
- See a doctor within a few days if you have a positive test with one-sided pain or bleeding.
Raise it at a routine appointment
- Book a routine visit for both of you if you have been trying for a year, or six months if you are 35 or older.
Sources
The evidence this explanation is built on.
- Infertility NHS
- Infertility World Health Organization
- Infertility MedlinePlus (NIH)
Who wrote and reviewed this
Every AskHer answer names its author. A clinically reviewed answer also names the clinician who signed it off — if no clinician is named below, it has not been clinically reviewed.
- Author
- AskHer Editorial (AI-assisted draft) AskHer's editorial team — not an individual clinician Works in English, தமிழ், हिन्दी
- Clinical reviewer
- Nobody yet No clinician has signed this answer off, and no person on the editorial team has read it yet. That is what the “Written with AI assistance” label means. It is queued for an editor to read, and then for a clinician who works in this area. The sources it was drafted against are listed above.
- Review status
- Written with AI assistance — not yet reviewed by a person
- Last reviewed
- Not yet reviewed by a person
- Version
- 1
Correction history
Substantive changes are listed, not quietly edited away.
No corrections have been made since this answer was first published.
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