Testing for and treating
sexually transmitted diseases (
STDs) in pregnant women deserves special attention. Treatment possibilities are limited because of potential risks for the developing fetus, and because effects can differ in pregnant compared with non-pregnant women,
re-infection may be missed because of the intrinsic delicacy of contact-tracing during pregnancy and because pregnant women are more reluctant to take the prescribed medication in its full dose, if at all. However, the devastating effects of some of these genital
infections far outweigh any potential adverse effects of treatment. Although active
syphilis has become a rarity in most Western countries, it is still prevalent in South America, Africa and South-East Asia.
Benzathine benzylpenicillin (2.4 million units once or, safer, twice 7 days apart) is the treatment of choice, although patients with
syphilis of longer standing require 3 weekly
injections as well as extensive investigation into whether there has been any damage due to
tertiary syphilis. Despite declining rates of
gonorrhea, the relative rate of
penicillinase-producing strains is increasing, especially in South-East Asia. The recommended treatment is intramuscular
ceftriaxone (125 or 250 mg) or oral
cefixime 400 mg. Despite good safety records after accidental use,
fluoroquinolones are contraindicated during pregnancy. An alternative to a
fluoroquinolone in pregnant women with combined
gonorrhea and chlamydial
infection is oral
azithromycin 1 or 2 g.
Azithromycin as a single 1 g dose is also preferable to
a 7 day course of
erythromycin 500 mg 4 times a day for patients with chlamydial
infection. Eradication of Haemophilus ducreyi in patients with
chancroid can also be achieved with these regimens or intramuscular
ceftriaxone 250 mg. Trichomonas vaginalis, which is often seen as a
co-infection, has been linked to an increased risk of
preterm birth. Patients infected with this parasite should therefore received
metronidazole 500 mg twice daily for 7 days as earlier fears of
teratogenesis in humans have not been confirmed by recent data.
Bacterial vaginosis is also associated with preterm delivery in certain risk groups, such as women with a history of
preterm birth or of low maternal weight. Such an association is yet to be convincingly proven in other women. The current advice is to treat only women diagnosed with
bacterial vaginosis who also present other risk factors for preterm delivery. The treatment of choice is oral
metronidazole 1 g/day for 5 days. The possible reduction of
preterm birth by vaginally applied
metronidazole or
clindamycin is still under investigation. In general, both test of cure and re-testing after several weeks are advisable in most pregnant patients with
STDs, because partner notification and treatment are likely to be less efficient than outside pregnancy and the impact of inadequately treated or recurrent disease is greater because of the added risk to the fetus. Every diagnosis of an STD warrants a full screen for concomitant
genital disease. Most ulcerative genital
infections, as well as abnormal vaginal flora and
bacterial vaginosis, increase the sexual transmission efficiency of HIV, necessitating even more stringent screening for and treating of STD during pregnancy.