Figure-28-18b. Punctuate calcifica tions at the endometrial myometrial inte rface in a patient with two prior dilatation and curettage procedures Intrauterine Contraception Devices Another cause of bright refectors within the uterus are intrauterine contraception deices(IUDs)(Fig. 28-19A and Fig. 28-19B) Ultrasound is helpful in locating an IUD when the string cannot be fe lt. The iUd should be located centrally within the endometrium. a straight shaft iud givesa bright linear reflectorwith entrance-exit refections and ring-down artifacts (23) The Lippes loop IUd also has a characteristic appearance with segmental reflectors with shadowing(see Fig.28-19B) 18/16 Intrauterine contraception devices(IUDs). Straight shaft IUD. Figure-28-19b. Lippes loop IUD. If the IUD is not visualized sonographically, radiogra phs should be obta ined to exclude an extrauterine location of an IUD Abnormal Endometrium Thick Endometrium Causes of a thickened endometrium indude the nomal secretory phase endometrium, endometrial hyperplasia, endometrial polyps, f braids, endometritis, early pregnancy, and complications of pregnancy. These are listed in (Table 28-13) Secretory Endometrium In women of menstrual age, the upper limitof nomal endometrial thickness is 14 to 16 mm. However, the endometrium can be thicker than this in the secretory phase and still be normal. An asymptomatic woman who is in the secretory phase by menstrual history, with a homogeneously echogenic thickened endometriumFigure - 28-18b. Punctuate calcifications at the endometrial myometrial interface in a patient with two prior dilatation and curettage procedures. Intrauterine Contraception Devices Another cause of bright reflectors within the uterus are intrauterine contraception devices (IUDs) (Fig. 28-19A and Fig. 28-19B ) . Ultrasound is helpful in locating an IUD when the string cannot be felt. The IUD should be located centrally within the endometrium. A straight shaft IUD gives a bright linear reflector with entrance-exit reflections and ring-down artifacts. (23) The Lippes loop IUD also has a characteristic appearance with segmental reflectors with shadowing (see Fig. 28-19B ). Figure - 28-19a. Intrauterine contraception devices (IUDs). Straight shaft IUD. Figure - 28-19b. Lippes loop IUD. If the IUD is not visualized sonographically, radiographs should be obtained to exclude an extrauterine location of an IUD. Abnormal Endometrium Thick Endometrium Causes of a thickened endometrium include the normal secretory phase endometrium, endometrial hyperplasia, endometrial polyps, fibroids, endometritis, early pregnancy, and complications of pregnancy. These are listed in (Table 28-13 ) . Secretory Endometrium In women of menstrual age, the upper limit of normal endometrial thickness is 14 to 16 mm. However, the endometrium can be thicker than this in the secretory phase and still be normal. An asymptomatic woman who is in the secretory phase by menstrual history, with a homogeneously echogenic thickened endometrium