Ob-Gyn Coding Alert

Many ob/gyn practices question how to correctly code and bill for amniocentesis when there are twins or triplets. The ingredients for optimal reimbursement lie in first understanding the procedures involved, the CPT coding choices and the diagnostic information that will support medical necessity for the procedures. Coding for multiple gestation then becomes a matter of numbers.

Amniocentesis can be defined as the transabdominal removal of fluid from the amniotic sac. The fluid is pathologically evaluated for genetic studies or to assess fetal lung maturity. The most advantageous time to do amniocentesis is at 16 weeks gestation. Direct ultrasound visualization helps the physician to precisely locate the area for obtaining fluid. Using ultrasound guidance, the amniotic sac is visualized, taking care to avoid passage through the placenta. Using a 20 to 22 gauge needle, 10 to 20 milliliters of fluid is withdrawn. The physician assesses the fetal heart tones at the end of the procedure.

CPT Coding for Amniocentesis

Even when the ob/gyn is providing global obstetrical services, amniocentesis is always a separately billable service. (See your CPT manual for a definition of the items included in the global obstetrical package.) There are individual CPT codes describing the amniocentesis procedure (59000) and ultrasonic guidance for amniocentesis (76946).

When the ob/gyn is performing both the amniocentesis and the ultrasound guidance, each of the above codes should be submitted on the claim. If the procedure is followed by a limited ultrasound to assess fetal heart tones, code 76815 (ultrasound, limited [fetal heart beat...]) can also be reported. If a radiologist is utilized to provide the ultrasonic guidance (and possibly the limited ultrasound), the ob/gyn will only bill for the amniocentesis. Note that a modifier -26 (professional component) would be added to each of the ultrasound procedure codes reported by the ob/gyn if the procedure is not performed in his or her office. This is because an ultrasound code submitted with no modifier implies that the physician used his or her own equipment to perform the procedure. In a setting other than the physicians office, the facility normally bills separately for the technical component of the service.

Coding for Multiple Gestation

For multiple gestation, the CPT codes submitted will depend on the method used for the procedure, says Melanie Witt, RN, CPC, MA, program manager for the Department of Coding and Nomenclature at the American College of Obstetricians and Gynecologists. Generally, each amniotic sac is aspirated. This can be accomplished by using dye to distinguish the two individual needle sticks. Amniocentesis of a twin gestation can also be done by first inserting the needle into the most proximal sac, then traversing the needle through the dividing membrane and aspirating the second sac.

If separate needle sticks are made into each amniotic sac, says Witt, code 59000 can be reported twice (or three times for a triplet pregnancy, etc.), or by listing the code once but indicating a quantity of two (or three) units on the claim form. Some payers will insist on the use of modifier -51 (multiple procedures) if code 59000 is listed more than once on the claim, but this rule varies greatly with different payers. If, however, just one needle stick is used to obtain fluid from both amniotic sacs, 59000 is reported only once, she adds. In this instance, if the physician feels that the procedure was significantly more difficult than usual, modifier -22 (unusual procedural services) can be added to 59000 to indicate this. When using the -22 modifier, always attach a procedure note with the claim.

The patient should be aware that there is a charge for both the lab services for the analysis of the amniotic fluid and the procedure. Some common lab tests are 82106 (alpha-fetoprotein, amniotic fluid chemistry analysis) and 83661 (lecithin-sphingomyelin ratio, quantitative).

ICD-9 Coding for Amniocentesis

Despite having coded the procedures correctly, many claims are denied or held for review because a medically necessary diagnosis is missing. More and more payers are looking at medical necessity for procedures and it will be important to select the ICD-9 code that most specifically supports the procedures performed.

When submitting claims for amniocentesis in the case of twins or triplets, be certain you are providing information about why the amniocentesis was medically necessary and support that diagnosis with the code indicating the presence of multiple gestation (651.03, twin pregnancy; or 651.13, triplets).

Below are some of the most common screening diagnosis codes reported as indications for amniocentesis. These codes would generally be used when a condition is suspected at the time of the procedure, but not confirmed until later. If the physician already knows there is a problem with the fetus, that condition would be coded instead.

V28.0 Screening for chromosomal anomalies by amniocentesis

V28.1 Screening for raised alpha-fetoprotein levels in amniotic fluid

V28.2 Other screening based on amniocentesis

V23.81 Elderly primigravida

V23.82 Elderly multigravida

Note that screenings diagnoses that are not clearly associated with a specific ICD-9 code are coded with the catch-all code V28.2 (other screening based on amniocentesis). This would be done, for example, with amniocentesis done to assess fetal lung maturity, because there is no specific code for this.

Coding Example

A 36-year-old patient is receiving obstetrical care for her first pregnancy. She has been followed for routine prenatal care and hasnt experienced any complications thus far. When she reaches her 15th week, twins are confirmed by ultrasound and the patient has a slightly elevated alpha-feto protein serum level. After discussing risks and benefits of amniocentesis with the patient, the ob/gyn orders and schedules an amniocentesis to evaluate the pregnancy for evidence of Down Syndrome. The doctors practice is equipped to provide the ultrasound visualization as well as the amniocentesis.

The diagnoses listed in Box 21 of the HCFA 1500 claim form should be linked to each CPT code, as follows:

CPT Code        	    Procedure	    Related with Diagnosis Code

59000		    Amniocentesis 	    V28.1
76946		    Ultrasound	    651.03, V28.1