HIV Seroconversion During Pregnancy and Mother-to-Child HIV Transmission:

Data from Enhanced Perinatal Surveillance, United States, 2005-2010

Singh S, Lampe M, Surendera Babu A, Rao S, Borkowf CB, Nesheim SR

XIX International AIDS ConferenceWashington, DC

July 26, 2012

No financial relationships to disclose

National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention Division of HIV/AIDS Prevention

Background

• In the US, the Centers for Disease Control and Prevention (CDC) recommends that opt-out HIV screening be included in the routine panel of prenatal screening tests for all pregnant women

• In addition, CDC recommends repeat third-trimester testing in areas with elevated HIV infection among pregnant women and women at high risk

• Decline in mother-to-child transmission (MCT) in the US since the early 1990sCDC. Revised Recommendations for HIV Testing of Adults, Adults, Adolescents, and Pregnant Women in Health-Care Settings.

MMWR, September 22, 2006, 55(RR14);1-17.

Background• Acquisition and transmission of HIV by women is

higher during pregnancy1

• Studies of acute infection during pregnancy in the US include:– Birkhead et al (2010)2 reported 13.8% (9/65) in New York

City of perinatal infections occurred in maternal primary infection

– Patterson et al (2007)3 reported 50% (3/6) in North Carolina of perinatal infections occurred in maternal primary infection

• Acute infection during pregnancy can lead to higher MCT due to increased viral load during acute infection41Mugo NR et al. AIDS 2011;25:1887-1895.

2Birkhead GS et al. Obstet Gynecol 2010;115:1247-55.3Patterson KB et al. AIDS 2007;21:2303-2308.

4Marinda ET et al. Int J Epid 2011;40:945-954.

Objectives

• To estimate the numbers of seroconversions during pregnancy (DP) and prior-to-pregnancy (PTP)

• To examine the maternal and infant characteristics and uptake of interventions between DP and PTP seroconverters

• To determine the proportion of perinatal infection which occur in the context of maternal primary infections

• To compare the MCT between DP and PTP seroconverters

Enhanced Perinatal Surveillance• EPS is a population‑ or facility-based surveillance

system for HIV‑infected mothers and their perinatally-exposed children

• EPS includes– Case ascertainment– Linking of mother‑infant pairs– Review of medical records for HIV testing history, prenatal care

and treatment, follow‑up to assess infection status of infants and initiation of HIV‑related care

• Data sources– Prenatal care records– Labor and delivery charts– Pediatric HIV medical records– Birth and death certificates– Mother’s HIV medical records for care– Health department record

GA

SC

TX

NY

LA

PR

MDDE

CTNJ

Methods

• HIV-infected women who delivered live infants 2005-2010

• EPS data linked with National HIV Surveillance System data through June 2011

• Determined number of DP and PTP seroconverters– DP seroconverters had negative HIV test during

pregnancy and positive HIV test during pregnancy, labor/delivery or 90 days after infant date of birth

– PTP seroconverters diagnosed prior to pregnancy

Methods• Comparisons were limited to DP and PTP

seroconverters

• Differences in characteristics and intervention uptake between DP and PTP seroconverters assessed by the chi-squared test

• Determined proportion of perinatal infection which occur in the context of maternal primary infections

• Calculated MCT among DP and PTP seroconverters

• Estimated annual percent change used to examine trends in percentages of DP and PTP seroconverters and MCT in seroconverter groups

Assumptions for Handling Missing Data

• Conditions– Used infant date of birth to replace missing HIV positive

test date – If HIV positive or negative tests missing, used additional

information from EPS questionnaire• Initiation of ART• Variable on mother’s HIV status

– HIV-positive before this pregnancy– HIV-positive at the time of delivery

RESULTS

HIV Seroconversions During Pregnancy and Prior-to-Pregnancy, EPS, 2005-2010

2005 2006 2007 2008 2009 2010 2005-2010

N (%) N (%) N (%) N (%) N (%) N (%) N (%)All Pregnancies 2,064 1,975 1,814 1,720 1,543 1,192 10,308

During Pregnancy 8 (0.4) 26 (1.3) 14 (0.8) 28 (1.6) 26 (1.7) 22 (1.9) 124 (1.2)*

Prior-to-Pregnancy

1,470 (71.2)

1,381(69.9)

1,283 (70.7)

1,204 (70.0)

1,061 (68.8)

836 (70.1) 7,235 (70.2)

Unclassifiable 586 (28.4) 568

(28.8) 517 (28.5) 488 (28.4) 456 (29.6) 334 (28.0) 2,949 (28.6)

*Estimated Annual Percent Change p<0.0001)

Maternal Characteristics Among DP and PTP Seroconverters, EPS, 2005-2010*

CharacteristicsDP

Seroconverter

N (%)

PTP Seroconvert

erN (%)

P-value

Age at Delivery (years) <0.0001

13-19 19 (15.3) 391 (5.4) 20-24 51 (41.1) 1374 (19.1) 25-34 46 (37.1) 3753 (52.2) 35-50 8 (6.5) 1677 (23.3)Race/Ethnicity 0.63 Black 76 (62.3) 4767 (66.9) Hispanic 33 (27.1) 1578 (22.1) White 12 (9.8) 710 (10.0) Other 1 (0.8) 74 (1.0)*Missing values were excluded from the analysis. The number of records for each variable does not sum to the total number of records due to missing information

Maternal Characteristics Among DP and PTP Seroconverters, EPS, 2005-2010*

CharacteristicsDP

Seroconverter

N (%)

PTP Seroconvert

erN (%)

P-value

Marital Status <0.005 Single 89 (88.1) 3899 (73.8) Married 11 (10.9) 1201 (22.7) Divorced/Separated/Widowed

1 (1.0) 181 (3.4)

Transmission Category 0.061 Injection Drug Use 5 (6.4) 646 (13.6) Heterosexual ContactƗ 65 (83.3) 3384 (71.4) Other 8 (10.3) 707 (14.9)Place of Birth 0.45 United States/Dependent Areas

91 (79.8) 5108 (76.8)

Non-United States Areas 23 (20.2) 1541 (23.2)*Missing values were excluded from the analysis. The number of records for each variable does not sum to the total number of records due to missing informationƗPersons whose transmission category is classified as heterosexual contact are persons who report specific heterosexual contact with a person known to have, or to be at high risk for, HIV infection (e.g., an injection drug user)

Infant Characteristics by Maternal Time of Seroconversion, EPS, 2005-2010*

Infant CharacteristicsDP

Seroconverter

N (%)

PTP Seroconver

terN (%)

P-value

HIV Infection Status of Infant

<0.0001

Infected 16 (13.0) 118 (1.7) Not Infected 79 (64.2) 5458 (77.8) Indeterminate 28 (22.8) 1439 (20.5)Gestational Age 0.44 Normal 80 (65.6) 4382 (62.2) Preterm 42 (34.4) 2668 (37.8)Birth Weight 0.087 Normal 104 (83.9) 5574 (77.4) Low Birth Weight 20 (16.1) 1628 (22.6)*Missing values were excluded from the analysis. The number of records for each variable does not sum to the total number of records due to missing information

Maternal and Infant Interventions Among DP and PTP Seroconverters, EPS, 2005-2010*

InterventionsDP

Seroconverter

N (%)

PTP Seroconver

terN (%)

P-value

Receipt of Prenatal Care 0.32 Yes 119 (96.8) 6591 (94.7) No 4 (3.3) 367 (5.3)Breastfeeding <0.00

01 Yes 24 (20.9) 52 (0.8) No 91 (79.1) 6807 (99.2)Mode of Delivery 0.003 Vaginal 66 (53.7) 2872 (40.8) Elective C-section 32 (26.0) 2966 (42.1) Non-elective C-section 23 (18.7) 1045 (14.8) C-section, unknown type

2 (1.6) 159 (2.3)

*Missing values were excluded from the analysis. The number of records for each variable does not sum to the total number of records due to missing information

Maternal and Infant Interventions Among DP and PTP Seroconverters, EPS, 2005-2010*

InterventionsDP Seroconverters

N (%)PTP

SeroconvertersN (%)

P-value

Prenatal ARV <0.0001

Yes 43 (34.7) 6193 (85.6) No 81 (65.3) 1042 (14.4)Intrapartum ARV

<0.0001

Yes 62 (50.0) 6290 (86.9) No 62 (50.0) 945 (13.1)Infant ARV <0.000

1 Yes 94 (75.8) 6873 (95.0) No 30 (24.2) 362 (5.0)Any ARV <0.000

1 Yes 94 (75.8) 6972 (96.4) No 30 (24.2) 263 (3.6)All Three ARV <0.000

1 Yes 42 (33.9) 5702 (78.8) No 82 (66.1) 1533 (21.2)*Missing values were excluded from the analysis. The number of records for each variable does not sum to the total number of records due to missing information

28-36 Weeks

36+ Weeks

Perinatal HIV Transmission Among DP and PTP Seroconverting Women, EPS, 2005-2010

2005 2006 2007 2008 2009 2010 2005-2010

N (%) N (%) N (%) N (%) N (%) N (%) N (%)

Perinatal HIV Transmission Among All Deliveries

56 (2.7) 35 (1.8) 42 (2.3) 29 (1.7) 26 (1.7) 22 (1.9) 210 (2.0)

Perinatal HIV Transmission AmongDP Seroconverters

2 (25.0) 3 (11.5) 2 (14.3) 3 (10.7) 2 (7.7) 4 (18.2) 16 (12.9)

Perinatal HIV Transmission Among PTP Seroconverters

32 (2.2) 22 (1.6) 21 (1.6) 17 (1.4) 14 (1.3) 12 (1.4) 118 (1.6)

Limitations

• EPS is a population-based and facility-based surveillance system and cannot be generalized to determine national estimates

• Surveillance areas use specific methods based on HIV-reporting laws or Institutional Review Board assurance which may result in variation in data collection methods

• Completeness of data including negative test date

Discussion

• From 2005 to 2010 there was a 25% estimated annual increase in the percent of DP seroconverters

• Unadjusted differences observed between PTP and DP seroconverters include mode of delivery, breastfeeding, HIV infection status of infant and ARVs

• MCT occurred among 2.0% of all deliveries and MCT among DP seroconverters was 12.9% and PTP seroconverters was 1.6%

• The proportion of perinatal infection which occur in the context of maternal primary infections was 7.6%

• Only 23.4% of DP seroconverters were tested during the CDC-recommended third trimester period

Conclusion

Mother-to-child transmission could be further reduced by greater adherence to CDC (2006) recommendations in the Revised Recommendations for HIV Testing of Adults, Adults, Adolescents, and Pregnant Women in Health-Care Settings

CDC’s HIV Testing Recommendations: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5514a1.htm/

AcknowledgementsCoauthors EPS ProgramMargaret Lampe Suzanne WhitmoreAruna Surendera Babu Gary WeeksShubha Rao Veena MinasandramCraig Borkowf Sabitha Dasari Steve Nesheim Renee Freeman

Grantee staff

Previous Work EPS ParticipantsStephanie SansomNan Ruffo

For more information please contact Centers for Disease Control and Prevention

1600 Clifton Road NE, Atlanta, GA 30333Telephone: 1-800-CDC-INFO (232-4636)/TTY: 1-888-232-6348E-mail: cdcinfo@cdc.gov Web: http://www.cdc.gov

The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.

National Center for HIV/AIDS, Viral Hepatitis, STD, and TB PreventionDivision of HIV/AIDS Prevention

Sonia Singh, PhD MHSEpidemiologist

HIV Incidence and Cases Surveillance BranchDivision of HIV/AIDS Prevention

National Center for HIV/AIDS, Viral Hepatitis, STD and TB PreventionCenters for Disease Control and Prevention

1600 Clifton Road NE, MS E-47Atlanta, GA 30333

Phone:  (404) 639-6337E-mail:  ssingh3@cdc.gov