Acne is caused by the hormonal changes of pregnancy. The severity varies between women and can vary in the same woman between pregnancies. Acne may affect the face alone or may be more widespread often affecting the back and torso.
Most cases are mild and require no treatment but severe cases may need to be seen by a doctor. A check for diabetes is always a good idea in these cases.
Treatments include improved facial hygiene, use of antiseptics and antibiotic creams that are safe in pregnancy.
There is a subgroup of women who are more likely to have acne in pregnancy and these women have a diagnosis of polycystic ovarian syndrome (PCOS).
They are often on contraceptive pills prior to pregnancy that improve their complexion. Acne begins to return when coming off the pill to achieve a pregnancy and usually worsens during pregnancy.
If acne is a problem, the above measures are instigated but the use of metformin may also be considered. This drug is usually used in pregnancy to control diabetes but has also been found to be useful in women with PCOS.