Fetal Anatomical Survey 
Medical specialty:  Radiology
 The patient is a 39-year-old gravida 3, para 2, who is now at 20 weeks and 2 days gestation.  This pregnancy is a twin gestation.  The patient presents for her fetal anatomical survey.  

PAST MEDICAL HISTORY:  ,The patient denies any significant past medical history.,PAST SURGICAL HISTORY: , The patient denies any significant surgical history.,MEDICATIONS: , The patient takes no medications.,ALLERGIES: , No known drug allergies.,SOCIAL HISTORY: , She denies use of cigarettes, alcohol or drugs.,FAMILY HISTORY: , No family history of birth defects, mental retardation or any psychiatric history.,DETAILS: , I performed a transabdominal ultrasound today using a 4 MHz transducer.  There is a twin gestation in the vertex transverse lie with an anterior placenta and a normal amount of amniotic fluid surrounding both of the twins.  The fetal biometry of twin A is as follows.  The biparietal diameter is 4.9 cm consistent with 20 weeks and 5 days, head circumference 17.6 cm consistent with 20 weeks and 1 day, the abdominal circumference is 15.0 cm consistent with 20 weeks and 2 days, and femur length is 3.1 cm consistent with 19 weeks and 5 days, and the humeral length is 3.0 cm consistent with 20 weeks and 0 day.  The average gestational age by ultrasound is 20 weeks and 1 day and the estimated fetal weight is 353 g.  The following structures are seen as normal on the fetal anatomical survey, the shape of the fetal head, the choroid plexuses, the cerebellum, nuchal fold thickness, the fetal spine and fetal face, the four-chamber view of the fetal heart, the outflow tracts of the fetal heart, the stomach, the kidneys, and cord insertion site, the bladder, the extremities, the genitalia, the cord, which appeared to have three vessels and the placenta.,Limited in views of baby A with a nasolabial region.,The following is the fetal biometry for twin B. The biparietal diameter is 4.7 cm consistent with 20 weeks and 2 days, head circumference 17.5 cm consistent with 20 weeks and 0 day, the abdominal circumference is 15.5 cm consistent with 20 weeks and 5 days, the femur length is 3.3 cm consistent with 20 weeks and 3 days, and the humeral length is 3.1 cm consistent with 20 weeks and 2 days, the average gestational age by ultrasound is 22 weeks and 2 days, and the estimated fetal weight is 384 g.  The following structures were seen as normal on the fetal anatomical survey.  The shape of the fetal head, the choroid plexuses, the cerebellum, nuchal fold thickness, the fetal spine and fetal face, the four-chamber view of the fetal heart, the outflow tracts of the fetal heart, the stomach, the kidneys, and cord insertion site, the bladder, the extremities, the genitalia, the cord, which appeared to have three vessels, and the placenta.  Limited on today's ultrasound the views of nasolabial region.,In summary, this is a twin gestation, which may well be monochorionic at 20 weeks and 1 day.  There is like gender and a single placenta.  One cannot determine with certainty whether or not this is a monochorionic or dichorionic gestation from the ultrasound today.,I sat with the patient and her husband and discussed alternative findings and the complications.  We focused our discussion today on the association of twin pregnancy with preterm delivery.  We discussed the fact that the average single intrauterine pregnancy delivers at 40 weeks' gestation while the average twin delivery occurs at 35 weeks' gestation.  We discussed the fact that 15% of twins deliver prior to 32 weeks' gestation.  These are the twins which we have the most concern regarding the long-term prospects of prematurity.  We discussed several etiologies of preterm delivery including preterm labor, incompetent cervix, premature rupture of the fetal membranes as well as early delivery from preeclampsia and growth restriction.  We discussed the use of serial transvaginal ultrasound to assess for early cervical change and the use of serial transabdominal ultrasound to assess for normal interval growth.  We discussed the need for frequent office visits to screen for preeclampsia.  We also discussed treatment options such as cervical cerclage, bedrest, tocolytic medications, and antenatal steroids.  I would recommend that the patient return in two weeks for further cervical assessment and assessment of fetal growth and well-being.,In closing, I do want to thank you very much for involving me in the care of your delightful patient.  I did review all of the above findings and recommendations with the patient today at the time of her visit.  Please do not hesitate to contact me if I could be of any further help to you.,Total visit time 40 minutes.