Much about the range of pathogens, frequency of coinfection, and clinical effects of reproductive tract infections (RTIs) among pregnant women remains unknown. We report on RTIs ( Mycoplasma genitalium , Chlamydia trachomatis , Neisseria gonorrhoeae , Trichomonas vaginalis , Treponema pallidum subspecies pallidum , bacterial vaginosis, and vulvovaginal candidiasis) and other reproductive health indicators in 699 pregnant women in Papua New Guinea during 2015–2017. We found M. genitalium , an emerging pathogen in Papua New Guinea, in 12.5% of participants. These infections showed no evidence of macrolide resistance. In total, 74.1% of pregnant women had > 1 RTI; most of these infections were treatable. We detected sexually transmitted infections (excluding syphilis) in 37.7% of women. Our findings showed that syndromic management of infections is greatly inadequate. In total, 98.4% of women had never used barrier contraception. These findings will inform efforts to improve reproductive healthcare in Papua New Guinea.