Sperm health

Being overweight can reduce your fertility because it lowers your sperm quality, including sperm count and movement. It also makes you more likely to produce abnormal sperm.

Being overweight also reduces testosterone (male sex hormone) production, which can cause sexual problems, such as difficulties getting an erection.

Sperm passes your genes from you to your child, and being overweight can affect how these genes function. This could mean your child’s health is affected either at birth or later in life.

If both you and your partner are a healthy weight, you’ll have an improved chance of pregnancy. The best way you can control your weight is through a balanced and nutritious diet and regular physical activity.

Cigarette smoking reduces sperm quality, giving you a lower sperm count, less semen, and poorer sperm movement. The more cigarettes you smoke, the worse your sperm quality is, although even ‘light’ smokers (less than 10 cigarettes a day) have reduced sperm quality. Heavy smoking (more than 20 cigarettes a day) at the time of conception increases your child’s risk of developing childhood leukaemia.

If you want to quit smoking, you can visit your doctor for support. It takes around three months for new sperm to fully develop, so it’s important to quit smoking at least three months before trying for a baby.

Having the occasional alcoholic drink is unlikely to affect your fertility. But heavy drinking can reduce sperm quality, lower testosterone production, and make it harder to achieve an erection. It can also lead to liver damage, which affects both your general and reproductive health. We don’t know exactly how much alcohol will impact your fertility, so consuming alcohol in moderation is your safest bet. We also recommend cutting out or reducing alcohol at least three months before trying for a baby.

Unlike women, who are born with all the eggs they will ever have, men produce sperm throughout their lives. While you can father children when you’re older, sperm quality declines with age. Partners of men aged 45 years or older take longer to fall pregnant and have a higher risk of miscarriage. And, although still rare, autism and other developmental conditions are slightly more common in children with older fathers. The risk of your child having a genetic or chromosomal problem is also increased. While it’s often beyond your control, if you want to become a father, sooner is better than later.

If you think you might have a sexually transmitted infection (STI), it’s important to get it checked and treated by a doctor right away. STIs such as chlamydia or gonorrhoea can damage the reproductive organs and cause infertility. Most STIs are easy to treat, and if you deal with the infection early, you’ll be fine. Getting treatment also reduces the chance of spreading the STI to your partner.

Using anabolic steroids (drugs that act like testosterone) lowers your fertility, with long-term and sometimes irreversible effects on sperm count and quality.

Some prescribed medications and recreational drugs can also lower fertility or sexual function. These include:

• Long-term use of painkillers that contain opiates

• Medications for treating depression and anxiety

• Chemotherapy or radiotherapy treatments for cancer

• Recreational drugs, such as marijuana, cocaine, and heroin.

If you’re concerned that your medication might affect your fertility, the best thing to do is speak to your doctor.

If you’re exposed to chemicals in your workplace, it’s important to wear protective clothing and follow occupational health and safety guidelines. When you’re trying for a baby, it’s best to avoid exposure to harmful chemicals, including pesticides, herbicides, heavy metals, and household chemicals. Many everyday plastics contain a particular group of chemicals called ‘endocrine disrupting chemicals’, which can also decrease your chances of pregnancy.

Of course, it can be hard to avoid all contact with things that harm your fertility. The best thing to do is to keep your exposure down as much as you can.