Pregnancy and blood fats

Your cholesterol and triglycerides naturally rise during pregnancy, as they're needed for the growth and development of the baby. Cholesterol is also needed to make the hormones oestrogen and progesterone which play a key role during pregnancy. 

Checking your cholesterol and triglyceride levels during pregnancy

We recommend that you don’t check your cholesterol levels during pregnancy because the results don’t reflect your usual levels, and could cause unnecessary worry.

We also advise against checking your triglyceride levels as these also rise during pregnancy.

If your cholesterol and triglycerides were raised before becoming pregnant

If you had high cholesterol before becoming pregnant the rise might be bigger, but this is temporary and does not pose any risk to you or your baby.

In rare cases, women with very high triglycerides before pregnancy develop severely raised triglycerides. This puts you at risk of acute pancreatitis, an uncommon but serious complication which can cause severe abdominal pain and fatty spots on the skin (eruptive xanthoma).

Pregnancy and familial hypercholesterolaemia (FH)

If you have familial hypercholesterolaemia (FH) and are otherwise healthy, there is no reason why you shouldn't get pregnant or breastfeeding. 

If you are pregnant or planning to get pregnant you should be under the care of specialists such as lipidologists at a lipid clinic, cardiologists and obstetricians. They will assess your risk of heart disease and, if you have a rarer, more severe form of FH, they should also screen you for aortic valve disease.

Taking cholesterol-lowering medicines during pregnancy

You should be advised to stop taking your cholesterol-lowering drugs, such statins and ezetimibe, for at least three months before trying to conceive. This allows time for the medicines to disappear completely from your body, known as a “washout” period. 

Keep off them throughout your pregnancy and whilst breastfeeding, and start again once the baby is weaned off breastmilk. 

These medicines can cross the placenta and may harm the baby. Although the risk is small, they can’t be considered safe while pregnant. 

For most women, it’s safe to stop taking cholesterol-lowering drugs throughout pregnancy and breastfeeding. The temporary rise in blood fats poses no risk to your baby and won’t affect your long-term health – especially if your cholesterol levels were well controlled before becoming pregnant and are brought down again afterwards. 

If you’re still taking your medicines when you become pregnant

If you are pregnant and you’re still taking your medicines, we strongly advise stopping them and contacting your GP, specialist, or other healthcare professional straight away. 

Are there any safe cholesterol medicines? 

Some lipid-lowering medicines such as bile acid sequestrants (also known as resins) don’t enter the bloodstream or cross the placenta, so, these can be prescribed during pregnancy and breastfeeding. 

They should be prescribed by a specialist. Bile acid sequestrants can stop some vitamins from being absorbed, so you might need folic acid and vitamin supplements. 

How soon will cholesterol and triglycerides levels return to normal?

Blood cholesterol tends to stay high for at least a month after giving birth. If you breastfeed, they can remain high until you stop.

Triglycerides can also stay high for up to a month after giving birth but might go back to normal sooner if you breastfeed.

Our specialists advise waiting at least six to eight weeks after giving birth before having a cholesterol test. If you are breastfeeding, wait until you’ve stopped,  least six to eight weeks.  This will give a more realistic picture of cholesterol and triglyceride levels.

If you have had complications or surgery, including a caesarean section, wait at least
three months before having a cholesterol test.   Cholesterol is needed to repair cell membranes and heal wounds after surgery so the results may not be reliable before then.