Having a family

Fertility for women with CF

Women with CF have anatomically normal reproductive tracts and normal hormonal function. The ovaries (where eggs are stored), the fallopian tubes (that join the uterus [womb] to the ovaries) and the uterus (where the fertilised egg implants itself and the baby develops) are all expected to be normal. There are reports that the mucus in and around the cervix is thicker than in women without CF.

Women with CF usually have normal menstrual cycles (periods) and are able to become pregnant. Increasing numbers of adult women with CF are becoming pregnant and giving birth to healthy babies, with minimal impact on their health. If you are healthy, with stable lung function, pregnancy is safe. However, pregnancy puts additional strain on your body, and can be a risk, particularly if you are unwell or have poor lung function.

Outcomes are better if pregnancy is planned. It is recommended that you discuss your plans with your CF team, and that you are as healthy as possible before conceiving.

There are some circumstances where pregnancy is not recommended because of the risk to the mother’s health. Women can become pregnant even if they are unwell, or have very low lung function, so it is important to use reliable contraception if you are sexually active and do not wish to become pregnant.

There are a number of things to think about when you are considering starting a family. These include the impact that parenting may have on your health and on your ability to look after yourself. It is also important to consider who is going to look after your children if you are unwell.

Genetic counselling is also important. Your biological children will inherit one copy of the CF gene from you, but they will not have CF unless they also inherit a copy of the CF gene from their father. The potential father can have genetic testing to find out if he is a carrier of a CF gene. This will tell you what the chance is that your child will have CF, which may affect your choices about how you start a family. It is also possible to have the foetus tested for CF during early pregnancy, using procedures known as chorionic villus sampling or amniocentesis.

If you do become pregnant, your CF team, your obstetric team (doctors and midwives who look after a woman during pregnancy), and possibly a neonatal team (doctors who look after a baby after it is born), will need to be involved in your care.

Fertility for men with CF

Men with CF produce sperm normally and their testes produce normal levels of testosterone (the male sex hormone). Testosterone is absorbed directly into the blood and is responsible for gains in muscle mass and sexual feelings. Men with CF have normal levels of testosterone and therefore normal sexual developmental and sexual function, including erections.

Approximately 98% of men with CF have problems with the development of the vas deferens, the duct that leads sperm from where it is produced in the testes to where it is stored prior to ejaculation. Therefore the ejaculate (semen) produced does not contain sperm. This means that most men with CF are infertile i.e. they cannot conceive a child through sexual intercourse. Men with CF are still able to have biological children using assisted reproductive technology.

As well as sperm, semen contains fluid made by glands called seminal vesicles. In men with CF, these glands don’t function normally and are sometimes absent. For men with CF, the ejaculate will contain fluid produced in other parts of the reproductive tract. Even though the volume of fluid may be reduced, sexual function is not affected. Sex will feel the same as it does for men who don’t have CF; it will also feel the same for their partners.

It is possible to find out if you are fertile or not through a test called semen analysis. You can ask your CF team or your GP if you are interested in having this test. There is no right time to have semen analysis. Some people want to know if they are fertile in adolescence, and other people may choose to wait until they are thinking about having children.

Before you have been tested and know about your fertility, it is best to protect any female partners from pregnancy – just in case. It is also important to remember that even if sex won’t lead to pregnancy, it is still possible to contract a sexually transmitted infection (STI). It is important to use condoms to protect from STIs.

There are a number of options available to men with CF who want to have children. For example, the sperm can be taken directly from the testis under local or general anaesthetic in a procedure known as microscopic epididymal sperm aspiration (MESA). The female egg is retrieved from the ovary using invitro fertilisation (IVF) techniques. The egg is then fertilised with the sperm, using intracytoplasmic sperm injection (ICSI), and the fertilised embryo is then placed into the woman’s uterus (womb). Artificial insemination with donor sperm is also possible and some men with CF choose to adopt children.

There are a number of things to think about when you are considering starting a family. These include the impact that parenting may have on your health and on your ability to look after yourself. It is also important to consider who is going to look after your children if you are unwell.

Genetic counselling is also important. Your biological children will inherit one copy of the CF gene change from you, but they will not have CF unless they also inherit a copy of the CF gene change from their mother. The potential mother can have genetic testing to find out if she is a carrier of the CF gene change. This will tell you what the chance is that your child will have CF, which may affect your choices about how you start a family. It is also possible to have the foetus tested for CF during early pregnancy, using procedures known as chorionic villus sampling or amniocentesis.