Dr Cordelia Han, Specialist in Obstetrics & Gynaecology, Raffles Hospital
Congratulations on your first pregnancy.
It is true that the pimples on your back and tummy are due to hormonal changes and calamine lotion
offers only a temporary relief as it cools the skin.
During pregnancy, due to the elevated prolonged hormonal effects, the skin can sometimes get very dry.
In some individuals, the sebaceous glands beneath the skin tries to compensate by producing more sebum, but
instead of lubricating the skin, pimples erupt as the duct openings get blocked.
You can try applying a non-perfumed medicated body lotion twice to thrice a day and see if the skin
condition improves. Most of the time this would suffice. In some extreme cases, a short course of antibiotics may
be prescribed in conjunction with the topical creams.
For some people, they may experience a rash that appears as blotches on the skin and is very itchy.
This condition is called PUPPP (pruritic urticarial papules and plaques of pregnancy).
This condition is the most common dermatosis (skin condition) of pregnancy. The cause was unknown until
recently when Dr Selim Aracting and colleagues from France reported studies linking PUPPP with cells from the
developing baby (foetus). Their studies suggest that foetal cells can invade the mother's skin during pregnancy,
and in some way cause this skin disorder to develop.
It typically starts on the tummy and spreads to the thighs and occasionally spreads to buttocks and
arms but the face is always spared. This commonly occurs in the third trimester around 34 weeks of pregnancy but
the face is never involved. It may appear to look like pimples (raised bumps but is itchy). The condition is
harmless to both baby and mother and resolves spontaneously after delivery. This is usually treated with steroid
creams but in extreme cases, oral steroids may be prescribed. With regards to pregnancy related rash, it is still
advisable to see your own Obstetrician.
As to your other queries, medicated oil contains methylated spirit and salicylate acid amongst other
ingredients. At present, there is no evidence to show that topical salicylic acid is harmful to baby but small
amounts do get absorbed into the skin. The occasional use of medicated oil for headache and mosquito bites is
Mothballs contain camphor and naphthalene. In some households, mothballs are used as room deodorizer,
which is no longer advisable. This is as prolonged exposure to the naphthalene fumes can cause headaches, nausea
and occasional vomiting. These are signs of toxicity that can occur in all individuals. However in a group of
individuals with a deficiency in the enzyme glucose-6-phosphate dehydrogenase (G6PD Deficiency), prolonged
exposure and inhalation of mothballs may cause the red blood cells to break down spontaneously as the glucose-6-
phosphate dehydrogenase (G6PD) enzyme that normally protects the red blood cells from specific chemical damage are
I suspect that you find the mothball scent refreshing due to the camphor component. May I suggest you
use natural essential oils that are sharp-smelling (e.g. bergamot, citronella or eucalyptus) instead.
Hope my answers have addressed your queries adequately.
Have a safe delivery.