Except in extreme cases usually not seen in this country, it is likely uncommon that anemia or poor nutrition predispose to infection. Bacterial colonization of the lower genital tract with certain microorganisms-for example, group B streptococcus,
Chlamydia trachomatis, Mycoplasma hominis, Ureaplasma ureayticum, and Gardnerela vaginalis-has been associated with an increased postpartum infection risk (Andrews, 1995; Jacobsson, 2002; Watts, 1990). Other factors associated with an increased infection risk include general anesthesia, cesarean delivery for multifetal gestation, young maternal age and nulliparity, prolonged labor induction, obesity, and meconium-stained amnionic fluid (Acosta, 2012; Leth, 2011; Siriwachirachai, 2014; Tsai,r2011).
Most female pelvic infections are caused by bacteria indigenous to the genital tract. Over the past 25 years, there have been reports of group A 3-hemolytic streptococcus causing toxic shock-like syndrome and life-threatening infection (Castagnola, 2008; Nathan, 1994). Prematurely ruptured membranes are a prominent risk factor in these infections (Anteby, 1999). In reviews by Crum (2002) and Udagawa (1999) and their colleagues, women in whom group A streptococcal infection was manifested before, during, or within 12 hours of delivery had a maternal mortality rate of almost 90 percent and fetal mortality rater> 50 percent. In the past 10 years, skin and sot-tissue infections due to community-acquired methicillin-resistant Staphylococcus aureus (A-MRSAJ have become common (Chap. 64, p. 1223). Although this variant is not a frequent cause of puerperal metritis, it is oten implicated in abdominal incisional infections (Anderson, 2007; Patel, 2007). Rotas and coworkers (2007) reported a woman with episiotomy cellulitis from CA-MRSA and hematogenously spread necrotizing pneumonia.
Common Pathogens. Bacteria responsible for most female genital tract infections are listed in Table
Most of these infections are polymicrobial, which enhances bacterial synergy.
TABLE 37-1 . Bacteria Commonly Responsible for Female Genital Infections
Gram-positive cocci-group A, B, and D streptococci, enterococcus, Staphylococcus aureus, Staphylococcus
Gram-negative bacteria-Escherichia coll� Klebsiella,
Mycoplasma and Chlamydia, Neisseria gonorrhoeae
Cocci-Peptostreptococcus and Peptococcus species Others-Clostridium, Bacteroides, Fusobacterium,