Nursing women may mistakenly assume that since St. John's wort and other herbs are "natural," they are safe. While case reports have described no adverse effects on pregnancy (Grush et al., 1998) or on infants exposed to St. John's wort through breast milk (Klier et al., 2002), data are too limited to recommend these herbs for use by pregnant or nursing women. An additional consideration among women of reproductive age is that St. John's wort induces the 3A4 isoenzyme of the cytochrome P450 system (Markowitz and DeVane, 2001). This enzyme metabolizes reproductive steroids and its induction can result in substantially lower efficacy of hormonal contraception. Women using hormonal contraceptives should be informed of this possibility and advised to use an alternative form of birth control.
Estrogen has been used to treat postpartum depression in two studies. In a double-blind study of 61 women with major depression that began three months postpartum, transdermal estrogen (as 17 ß-estradiol 200 µg/day) led to a rapid improvement in mood (Gregoire et al., 1996). The mean score on the depression rating scale (Edinburgh Postnatal Depression Scale) remained elevated among the women on estrogen, however, suggesting that the antidepressant effect was not robust.
In a second study, 23 women with major depression that occurred in the six months following delivery took sublingual estrogen (as micronized 17 ß-estradiol, mean dose=4.8 mg/day after the first week) (Ahokas et al., 2001). After two weeks of treatment, 19 of the women experienced a clinical recovery as defined by a score <7 on the Montgomery-Asberg Depression Rating Scale (MADRS).
Estrogen may appeal to patients because it is a naturally occurring substance. Also, since estrogen levels precipitously decline following delivery, some women may believe that estrogen deficiency underlies postpartum depression. However, postpartum depression has not been conclusively linked to low levels of estrogen or any other hormone (Hendrick et al., 1998). Patients should be warned that the use of estrogen is associated with several risks, including endometrial hyperplasia and thromboembolism. It also diminishes the production of breast milk in nursing mothers. Given these considerations, estrogen does not appear to have a primary role in the treatment of postpartum depression at this time.
The treatment of postpartum depression with natural progesterone(Drug information on progesterone) has yet to be evaluated in a clinical trial. Natural progesterone is metabolized into allopregnanolone, a neuroactive steroid that enhances 
-aminobutyric acid (GABA) in the central nervous system, producing anxiolytic and hypnotic effects (Rupprecht and Holsboer, 1999). Natural progesterone may therefore have a role in the treatment of postpartum depression with comorbid anxiety. This possibility should be explored in future treatment studies of postpartum depression.
Synthetic progestogens do not help postpartum depression and may, on the contrary, exacerbate the symptoms (Lawrie et al., 2000). Unlike natural progesterone, synthetic progestogens (e.g., medroxyprogesterone(Drug information on medroxyprogesterone)) are not metabolized into GABA-ergic neuroactive steroids.
Sleep deprivation improves depressive symptoms in approximately 40% to 60% of patients suffering from depression and has the advantage of very quick onset (Giedke and Schwarzler, 2002; Riemann et al., 2001). It may present a quick, easy and free treatment intervention for women with postpartum depression. On the other hand, sleep deprivation has been reported to exacerbate mood in new mothers, and improvement of children's disrupted sleep is associated with significant improvement in maternal mood (Armstrong et al., 1998). Sleep deprivation resulting from multiple, erratic awakenings may produce a very different effect compared to controlled and predictable sleep deprivation. Further research on sleep deprivation would be useful, including strategies to prolong its benefits. Sleep deprivation is probably not a reasonable intervention for new mothers who are generally trying to sleep whenever the baby sleeps, but it may benefit mothers of older infants who are able to sleep through the night.
Bright light therapy produced antidepressant effects in a small study of 16 pregnant patients with major depression (Oren et al., 2002) and in two women with postpartum-onset major depression (Corral et al., 2000). Since it is well-tolerated and does not produce medication exposure to the nursing infant, it may become a promising treatment for postpartum depression.
