Acne and pregnancy interact in a variable way. In the majority, pregnancy has a beneficial effect on the activity of acne, and this is through the sebosuppressive effect of estrogens. In a small number of cases, there is a flare-up of acne requiring active intervention, especially if scarring is a threat. Acne may also appear for the first time during pregnancy.
There are reports of women experiencing acne only during pregnancies. If an acne patient during active treatment conceives then careful assessment of teratogenicity issues needs to be carried out and the safety to carry the pregnancy to term needs to be determined. There are times when a medical termination of pregnancy may be a safer option.
It is difficult and challenging to treat acne in a pregnant woman as most drugs are contraindicated or considered unsafe. For comedonal acne, BPO (2.5-5.0%) is safe and may be sufficient. Azelaic acid, although not contraindicated, is not recommended. Topical retinoids are controversial in pregnancy because of concerns of systemic absorption. However, in clinical studies of topical adapalene and tazarotene, plasma concentrations were found to be below 3 nM, which is similar to or lower than endogenous tretinoin, suggesting that the teratogenic potential of topical retinoids is negligible.
Inflammatory acne may be treated with BPO or topical antibiotics, or a combination of the two. Macrolides are generally regarded as safe in pregnancy. Oral erythromycin is permitted for scar-threatening acne, and may be given for 3-9 months as needed. Presumably, it is just as safe to administer newer macrolides, roxithromycin, clarithromycin, and azithromycin, in usual acne dosages. Any such intervention must be well justified, and the perceived benefits must outweigh the uncertainties. Tetracyclines (including doxycycline, minocycline, lymecycline) being unsafe in the second and third trimester of pregnancy (vide supra) are best avoided at all stages of pregnancy, whereas oral retinoids being highly teratogenic are absolutely contraindicated.
Source: Kubba R, Bajaj AK, Thappa DM, Sharma R, Vedamurthy M, Dhar S, Criton S, Fernandez R, Kanwar AJ, Khopkar U, Kohli M, Kuriyipe VP, Lahiri K, Madnani N, Parikh D, Pujara S, Rajababu KK, Sacchidanand S, Sharma VK, Thomas J. Acne in India: Guidelines for management – IAA Consensus Document: Acne in pregnancy. Indian J Dermatol Venereol Leprol [serial online] 2009 [cited 2009 Mar 2];75(Suppl 1):S59. Available from: http://www.ijdvl.com/text.asp?2009/75/7/59/45491