Incidental Pregnancy: Pregnancy Categories and Various Cases


Incidental pregnancy is a case when the patient has come for some other concern but has been diagnosed pregnant. As per ICD 10 coding, incidental pregnancy is a test that proves that the patient is pregnant. But it is not what they are hoping for. Like a patient has come with a sinus pain or pain in the spines. After check up and tests, it is found that she is pregnant.

Sometimes you go to doctor with upset stomach to get a cure. But you get bumped with pregnancy news.

Another case may be taken of a trauma patient. A patient suffering from abdominal trauma may come to do a CT or a regular x-ray. But out of the blue she can get a report of pregnancy which she or her family is expecting for.

Categories and Various Cases of Incidental Pregnancy

incidental pregnancy


Pregnancy categories

According to Food and Drug Administration of United States there are many categories related to pregnancy. They are discussed below:

Category A

A well detailed research has failed to exhibit a risk related to the fetus during the pregnancy’s first trimester. There are not enough studies done to demonstrate the fatality in the trimesters as well.

Category B


Studies on animal reproduction have failed to exhibit the risk to fetus. There are not much well-controlled researches on pregnant woman. A well-controlled study            could not demonstrate the risk to fetus in any of the trimesters.

Category C

Studies on animal reproduction have revealed that there might be an adverse effect on the fetus. Over that one cannot find well-controlled or adequate studies on humans. But the potential benefits might warrant apply the drug in women who are pregnant. It can be done despite the potential risk.

Category D


As per the investigational and marketing studies and experiences data there is a positive evidence of fetal risk. This risk may arise due to adverse effects in humans. But just like Category C the potential benefits might warrant apply the drug in women who are pregnant. It is done despite the potential risk.

Category X

Reproduction studies both in humans and animals have exhibited abnormalities of the fetus. There is also evidence of fetal risk in human due to the adverse reaction. All these have been proved as per the data provided by marketing or investigational experiences and studies.

Again under this category, the risk of using of drug clearly outweighs the probable benefits in a pregnant woman.


ICD-10 Pregnancy coding guidelines

Chapter 15 of ICD-10 coding contains information related to childbirth, pregnancy and Peurperium. It comprises categories O00-O99. The first trimester starts from the day 0 and continues till the third week of pregnancy. The second trimester extents from the 14th week till the 27th week. In this category of category, different aspects have to be taken into consideration. Like various maternal problems related to delivery and others, high risk during pregnancy period and abortive effects.

Chapter 15 contains codes related to various cases

Obstetric cases can acquire codes from this chapter. The code range is O00-O9A related tp Pregnancy, Childbirth and Peurperium. Others codes can be used in the conjunction with this chapter to specify conditions further.

Let us discuss some codes related to pregnancy:


O00-O08 pregnancy code range:

This code range is related with abortive results. The sub- codes under this main code corresponds to codes of other categories like 630-639 of ICD-9-CM. This code contains conditions like tubal pregnancy, miscarriage, ectopic pregnancy and other pregnancy related complications and abortive outcomes.

Code O09 code range:

This code range supervises high-risk conditions during pregnancy. The codes that fall under this basic code range match up with the codes in the category of V23 of ICD-9-CM. It has details about high risks related to pregnancy that might occur due to various conditions. Some of the conditions are ectopic pregnancy, history related to infertility, meager reproductive health condition, grand muliparity and many more.


O10-O16 code range:

This subsection code range deals with Proteinuria, Edema and Hypertensive Disorders during pregnancy period. The various conditions that are coded here are hypertensive heart diseases, chronic kidney diseases that are hypertensive and hypertension.

O80-O82 code range:

This subsection corresponds to the codes that are in the categories 650 and 669 of the ICD-9-CM. the different conditions included under this range are a total complicated delivery which is basically used to state and report an unexceptional birth or that is without episiotomy. It also covers other conditions related to cesarean delivery that doesn’t have any indication.


O85-O92 code range:

This code range contains information’s about the conditions related to Puerperium and complications arising out of it. The various conditions that are discussed here are varicose veins, pyrexia, puerperal sepsis and many more.

O94-O9A code range:

This code range deals with obstetric conditions. It corresponds to various other categories of codes like 647-649 of the ICD-9-CM. The coded conditions are parasitic and maternal infectious diseases, anemia, abuse and many more.


Some general guidelines:

  • ICD-10 often classifies conditions according to the trimesters. It uses the final character to choose the trimester. But it does not require need to use the fifth number in order to identify whether an encounter is for the delivery, postpartum or for ante partum
  • The reason for care can be for obstetric or anything related to pregnancy management. But if it is not then the coder may assign any secondary code of pregnant state, Z33.1, incidental.
  • Admission to the hospital may lead to delivery. In such a situation the coder may look for and assign any secondary code. The codes can be from Z37 category, Outcome of Delivery.
  • Routine prenatal doctor visits without any serious complications will make the coder seek for first listed code. This codes can be from Z34 category, encounter for the supervision related to normal pregnancy.
  • There might be cases where the pregnant mother suffers from a pre-existing condition of hypertensivity. In such cases the coder must assign any secondary code. Such code must be from an appropriate category that can specify hypertension, kidney disease etc.

So there is nothing to worry about incidental pregnancy. If you face such problem in the future do consult a doctor who will guide you to have a safe pregnancy period.