CDC H IV/A IDS Fact Sheet

Mother-to-Child (Perinatal)

HIV Transmission and 

Prevention

1-800-CDC-INFO (232-4636)

In English, en Español

24 Hours/Day

cdcinfo@cdc.gov

http://www.cdc.gov/hiv 

October 2007

HIV transmission from mother to child during 

pregnancy, labor and delivery, or breastfeeding is 

called perinatal transmission. Research published 

in 1994 showed that zidovudine (ZDV) given 

to pregnant women infected with HIV and 

their newborns reduced the risk for this type of 

HIV transmission [1]. Since then, the testing of 

pregnant women and treatment for those who are 

infected have resulted in a dramatic decline in the 

number of children perinatally infected with HIV. 

However, much work remains to be done: about 

100–200 infants in the United States are infected 

with HIV annually. Many of these infections 

involve women who were not tested early enough 

in pregnancy or who did not receive prevention 

services.

Perinatal HIV transmission is the most common 

route of HIV infection in children and is now the 

source of almost all AIDS cases in children in the 

United States. Most of the children with AIDS are 

members of minority races/ethnicities [2].

STATISTICS

HIV/AIDS in 2005

The following bullets are data from the 33 states 

with long-term, confidential name-based HIV 

reporting. For a list of the 33 states, see the box at 

the end of this fact sheet.

• HIV/AIDS was diagnosed for an estimated 142 

children less than 13 years old who had been 

infected with HIV perinatally [2].

• An estimated 6,051 persons who had been 

infected with HIV perinatally were living with 

HIV/AIDS at the end of 2005 [2].

• Of the perinatally infected persons living with 

HIV/AIDS at the end of 2005, an estimated 

66% were black (not Hispanic or Latino), and 

an estimated 20% were Hispanic/Latino [2].

AIDS in 2005

• Of the estimated 68 children for whom AIDS 

was diagnosed during 2005, an estimated 67 had 

been infected with HIV perinatally [2].

• An estimated 46 persons with AIDS who had 

been infected with HIV perinatally died in 

2005 [2].

• Since the beginning of the epidemic, AIDS has 

been diagnosed for an estimated 8,460 children 

who were infected perinatally. Of those, an 

estimated 4,800 (57%) had died [2].

• Over the course of the epidemic, the number 

of AIDS cases associated with perinatal 

transmission has decreased dramatically. 

This decrease is largely due to the increased 

identification of women infected with HIV 

and timely interventions to prevent perinatal 

transmission [3]. 
Mother-to-Ch ild (Per inatal) H IV Transm iss ion and PreveNt ion

2

AIDS cases due to the perinatal 

transmission of HIV infection, by year of 

diagnosis, 2001–2005, United States [2]

Race/ethnicity of children (<13 years) with 

AIDS diagnosed during 2005 (includes all 

children with a diagnosis of AIDS, not just 

those who contracted HIV perinatally)

Note. Includes children of unknown race or multiple 

races. Because the total is less than 100, this graph 

shows numbers, not percentages. No cases of AIDS were 

diagnosed among American Indian/Alaska Native children.

RISK FACTORS AND BARRIERS 

TO PREVENTION

Lack of Awareness of HIV Serostatus

The main risk factor, which is also a barrier to 

the prevention of perinatal HIV transmission, is 

lack of awareness of HIV status among pregnant 

women.

• Because approximately 25% of all people 

infected with HIV do not know their HIV 

status [4], many women who are infected with 

HIV may not know they are infected. This is 

why CDC has recommended routine, optout1

 HIV testing for all pregnant women [5]. 

If women are tested early in their pregnancy, 

those who are infected can be given therapy to 

improve their own health and reduce the risk of 

transmitting HIV to the baby.

•In the United States, without antiretroviral 

therapy, approximately 25% of pregnant 

women infected with HIV will transmit the 

virus to their child [1].

Uneven HIV Testing Rates

Recent CDC studies found that HIV testing 

rates for pregnant women varied widely and 

that a relatively high proportion of women of 

childbearing age were unaware that treatment 

is available to reduce the risk for perinatal 

transmission [6, 7]. In a 2002 study of HIV testing 

in the United States, 31% of the 748 women who 

had recently been pregnant reported that they had 

not been tested during prenatal care [8]. Continued 

efforts are needed to ensure that all women know 

their HIV status as early as possible in pregnancy.

• Because of prenatal testing, most HIV-infected 

women know they are infected before they 

give birth [3]. Still, testing rates in the United 

States remain uneven: 18% of the women 

in another study were not tested until after 

childbirth [9].

• State HIV testing rates differ, depending on the 

testing approach used. For example, rates for 

1

Opt-out HIV testing: women are told that an HIV test will be included in 

the standard group of prenatal tests but that they may decline HIV testing.
3

Mother-to-Ch ild (Per inatal) H IV Transm iss ion and PreveNt ion

states using the opt-in2 approach ranged from 

25% to 69%. The opt-out approach results in 

higher testing rates [6]. CDC recommends the 

opt-out approach [5], but in many prenatal 

settings, it has not been implemented. 

CDC is working with state and local health 

departments and national organizations to 

increase the rates of HIV testing among 

pregnant women.

PREVENTION

To reduce further the incidence of HIV infection, 

CDC announced a new initiative, Advancing 

HIV Prevention (AHP) (http://www.cdc.gov/hiv/

partners/AHP.htm), in 2003 [10]. This initiative 

comprises 4 strategies: making HIV testing a 

routine part of medical care, implementing new 

models for diagnosing HIV infections outside 

medical settings, preventing new infections by 

working with HIV-infected persons and their 

partners, and further decreasing perinatal HIV 

transmission.

In 2006, CDC published “Revised 

Recommendations for HIV Testing of Adults, 

Adolescents, and Pregnant Women in Health-Care 

Settings” [5]. To further reduce the number of 

children who are infected with HIV perinatally, 

these recommendations called for routine opt-out 

HIV screening for all pregnant women, with repeat 

HIV screening in the third trimester for women 

who meet 1 or more of 4 criteria (for example, 

women at high risk and women who receive health 

care in jurisdictions with elevated rates of HIV 

infection among women). Women whose HIV 

status is unknown at the time of labor should be 

offered opt-out screening with a rapid HIV test.

In support of these recommendations, CDC 

developed a social marketing campaign—One 

Test. Two Lives. —with the goal of ensuring 

that all women are tested for HIV early in their 

pregnancy. The campaign provides quick access 

to a variety of resources for health care providers, 

along with materials for their patients, to 

2

Opt-in HIV testing: women are provided pretest counseling and must specifically consent to an HIV test.

encourage universal voluntary prenatal testing for 

HIV. Information on this campaign can be found at 

http://www.cdc.gov/1test2lives.

Already, perinatal HIV prevention has saved lives. 

• The number of children with a diagnosis of 

AIDS who had been perinatally exposed to 

HIV declined from 118 in 2001 to 67 in 2005 

[2]. The number of infants infected with HIV 

through perinatal transmission decreased 

from an estimated peak of 1,650 HIV-infected 

infants born in 1991 [3] to 96–186 infants born 

in 2004 [11].

• Antiretroviral therapy administered to the 

mother during pregnancy, labor and delivery, 

and then to the newborn, as well as elective 

cesarean section for women with high viral 

loads (more than 1,000 copies/ml), can reduce 

the rate of perinatal HIV transmission to 

2% or less [12]. If medications are started 

during labor and delivery, the rate of perinatal 

transmission can still be decreased to less than 

10% [13].

CDC funds 15 state and local health departments 

to conduct perinatal HIV prevention programs. 

The following are examples of CDC-funded 

perinatal HIV prevention programs:

• Comprehensive social marketing campaigns in 

New York to encourage women to be tested for 

HIV and to get early prenatal care [14]

• Tracking and surveillance programs in 

Louisiana to identify HIV-infected pregnant 

women who are not receiving medical care and 

connect these women to health care 

resources [15]

• Outreach programs in Florida for women in 

nontraditional settings, including jails [15]

• Intensive provider education programs in New 

Jersey to disseminate the state standard of care 

for perinatal HIV prevention, educate providers 

about interventions for perinatal prevention, 

and implement rapid HIV testing for women 

whose HIV status is unknown at the time of 

labor and delivery
4

Mother-to-Ch ild (Per inatal) H IV Transm iss ion and PreveNt ion

• Technical assistance to hospitals in Illinois to 

increase readiness and compliance with the 

Illinois Perinatal HIV Prevention Act [16]

• Regional strategic planning workshops 

supported by CDC-funded national 

organizations to help hospitals implement rapid 

HIV testing for women in labor whose HIV 

status is unknown [17]

REFERENCES

1. Connor EM, Sperling RS, Gelber R, et al. 

Reduction of maternal-infant transmission of human 

immunodeficiency virus type 1 with zidovudine 

treatment. New England Journal of Medicine

1994;331:1173–1180.

2. CDC. HIV/AIDS Surveillance Report, 2005. Vol. 

17. Rev. ed. Atlanta: US Department of Health and 

Human Services, CDC; 2007:1–54. Available at http://

www.cdc.gov/hiv/topics/surveillance/resources/

reports/2005report/. Accessed September 25, 2007.

3. Lindegren ML, Byers RH, Thomas P, et al. Trends 

in perinatal transmission of HIV/AIDS in the United 

States. JAMA 1999;282:531–538.

4. Marks G, Crepaz N, Janssen RS. Estimating sexual 

transmission of HIV from persons aware and unaware 

that they are infected with the virus in the USA. AIDS

2006;20(10):1447–1450.

5. CDC. Revised recommendations for HIV testing of 

adults, adolescents, and pregnant women in health-care 

settings. MMWR 2006;55(RR-14):1–17. 

6. CDC. HIV testing among pregnant women―United 

States and Canada, 1998–2001. MMWR

2002;51:1013–1016.

7. Anderson JE, Ebrahim S, Sansom S. Women’s 

knowledge about treatment to prevent mother-to-child 

human immunodeficiency virus transmission. Obstetrics 

and Gynecology 2004;103:165–168.

8. Anderson JE, Sansom S. HIV testing among U.S. 

women during prenatal care: findings from the 2002 

National Survey of Family Growth. Maternal and Child 

Health Journal 2006;10(5):413–417.

9. Aynalem G, Mendoza P, Mascola L, Frederick T. Trends 

and associated factors in timing of maternal HIV status 

identification: implications for preventing perinatal HIV/

AIDS infection. National HIV Prevention Conference; 

August 2003; Atlanta. Abstract M2-B0303. 

10. CDC. Advancing HIV Prevention: New Strategies for 

a Changing Epidemic—United States, 2003. MMWR

2003;52(15):329–332.

11. McKenna MT, Hu X. Recent trends in the incidence 

and morbidity associated with perinatal human 

immunodeficiency virus infection in the United States. 

American Journal of Obstetrics and Gynecology

2007;197(3)(suppl 1):S10–S16.

12. Cooper ER, Charurat M, Mofenson LM, et al. 

Combination antiretroviral strategies for the treatment 

of pregnant HIV-1–infected women and prevention 

of perinatal HIV-1 transmission. Journal of Acquired 

Immune Deficiency Syndromes 2002;29(5):484–494.

13. Wade NA, Birkhead GS, Warren BL, et al. Abbreviated 

regimens of zidovudine prophylaxis and perinatal 

transmission of the human immunodeficiency virus. New 

England Journal of Medicine 1998;339(20):1409–1414.

14. Doyle PA, Rogers P, Gerka M, et al. Implementation of a 

comprehensive model for recruiting pregnant women at 

risk for HIV and late or no prenatal care. National HIV 

Prevention Conference; August 2003; Atlanta. Abstract 

T1-C1002.

15. Clark J, Sansom S, Simpson BJ, et al. Promising 

strategies for preventing perinatal HIV transmission: 

model programs from three states. Maternal and Child 

Health Journal 2006;10(4):367–373.

16. Bryant Borders AE, Eary RL, Olszewski Y, et al. 

Ready or not—intrapartum prevention of perinatal HIV 

transmission in Illinois. Maternal and Child Health 

Journal 2007;11(5):485–493.

17. Burr CK, Lampe MA, Gross E, Clark J, Jones R. A 

strategic planning approach to influencing hospital 

practice regarding rapid HIV testing in labor and 

delivery. Annual Meeting of the American Public Health 

Association; 2007; Washington DC. Abstract 161680.
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Mother-to-Ch ild (Per inatal) H IV Transm iss ion and PreveNt ion

Understanding HIV and AIDS Data

AIDS surveillance: Through a uniform system, CDC 

receives reports of AIDS cases from all US states and 

dependent areas. Since the beginning of the epidemic, 

these data have been used to monitor trends. The data 

are statistically adjusted for reporting delays and for 

the redistribution of cases initially reported without risk 

factors. As treatment has become more available, trends 

in new AIDS diagnoses no longer accurately represent 

trends in new HIV infections; these data now represent 

persons who are tested late in the course of HIV 

infection, who have limited access to care, or in whom 

treatment has failed.

HIV surveillance: Monitoring trends in the HIV 

epidemic today requires collecting information on 

HIV cases that have not progressed to AIDS. Areas 

with confidential name-based HIV infection reporting 

requirements use the same uniform system for data 

collection on HIV cases as for AIDS cases. A total 

of 33 states (Alabama, Alaska, Arizona, Arkansas, 

Colorado, Florida, Idaho, Indiana, Iowa, Kansas, 

Louisiana, Michigan, Minnesota, Mississippi, Missouri, 

Nebraska, Nevada, New Jersey, New Mexico, New 

York, North Carolina, North Dakota, Ohio, Oklahoma, 

South Carolina, South Dakota, Tennessee, Texas, Utah, 

Virginia, West Virginia, Wisconsin, and Wyoming) 

have collected these data for at least 5 years, providing 

sufficient data to monitor HIV trends and to estimate 

risk behaviors for HIV infection. 

HIV/AIDS: This term is used to refer to 3 categories of 

diagnoses collectively: (1) a diagnosis of HIV infection 

(not AIDS), (2) a diagnosis of HIV infection and a later 

diagnosis of AIDS, and (3) concurrent diagnoses of 

HIV infection and AIDS.

For more information . . . 

CDC HIV/AIDS

http://www.cdc.gov/hiv

CDC HIV/AIDS resources

CDC-INFO

1-800-232-4636

Information about personal risk and where to 

get an HIV test

CDC National HIV Testing Resources

http://www.hivtest.org

Location of HIV testing sites

CDC National Prevention Information 

Network (NPIN)

1-800-458-5231

http://www.cdcnpin.org

CDC resources, technical assistance, and 

publications

AIDSinfo

1-800-448-0440

http://www.aidsinfo.nih.gov

Resources on HIV/AIDS treatment and 

clinical trials