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Perinatal HIV Transmission
and Birth Options for HIV positive Mothers
by Laura Jones
Many people are misinformed
about the risks of perinatal HIV transmission, including many
healthcare providers. Some people mistakenly believe that
all babies born to HIV positive women will be infected, or
that HIV positive women are too sick to have healthy pregnancies
and give birth to healthy children. Many people also don’t
know that there are ways to greatly reduce the risk of mother-to-child
HIV transmission. About 25% of children born to HIV positive
women who receive no treatment or interventions against perinatal
HIV transmission become infected with HIV—that means
an average of 25 out of 100 babies, or 1 in 4, can pick up
HIV from their mothers during pregnancy, birth, or afterward
from breastfeeding. But perinatal HIV infection rates can
drop to as low as 1% or 2% for babies whose mothers are able
to use combination antiretroviral therapy during pregnancy,
AZT or nevirapine prophylaxis during labor and after birth,
and choose the birth option that’s safest, according
to maternal viral load levels, for both mother and baby.
You are a good place for
your baby to grow, and you deserve respectful care. If your
HIV care specialist or prenatal care provider tries to dissuade
you from becoming pregnant or recommends you terminate a wanted
pregnancy, get another provider! With good care and support,
your risk of transmitting HIV to your fetus or baby is very
low. Don’t let that worry stop you if you want to be
a mother.
How perinatal HIV transmission
happens
A fetus (your baby from 8
weeks gestation until birth) or newborn can become infected
with HIV through contact with virus in their mother’s
blood, cervical and vaginal secretions, and breast milk. It’s
the mom’s HIV status that matters, not the father’s—HIV
transmission to babies is all about the virus in their mom’s
fluids, not in their father’s semen. If the mom stays
HIV negative throughout her pregnancy, there’s no risk
to the baby even if the father is HIV positive.
No one knows the exact mechanisms
involved in perinatal transmission, but it’s believed
to occur three different ways:
Prenatally (in utero):
Some babies acquire HIV because the virus crossed the placenta
during pregnancy—this doesn’t happen very often,
but it can. During pregnancy, the mother’s blood supply
is connected to the fetal blood supply via the umbilical cord
and placenta. The mother and the baby do not share the same
blood supply, but sometimes HIV in the mother’s blood
is able to cross the placenta and infect the baby. The following
conditions can increase the risk of transmission during gestation:
- Becoming infected with HIV during
pregnancy. A person’s viral load is very high right
after they acquire the virus, and a high viral load increases
the transmission risk to the fetus.
- Infections of the chorion, amniotic
membranes, or reproductive tract. Sexually-transmitted vaginal
infections like chlamydia, gonorrhea, and trichomoniasis
can cause a spike in the pregnant woman’s viral load,
which can in turn increase the risk of transmission to her
fetus.
- Placenta Previa. This is when
the placenta grows over part or all of the cervix—a
condition that can lead to heavy bleeding before or during
labor. Placenta previa often corrects itself as the uterus
expands during pregnancy.
At
birth: During labor and delivery, the baby comes into
contact with her/his mother’s blood and cervical/vaginal
secretions while passing through the cervix and vagina. Research
indicates that the majority of babies who pick up HIV infection
from their mothers probably acquire the virus during the birth
process.
During
breastfeeding: There have been several documented cases
in which HIV has been transmitted through breastfeeding. HIV
has been isolated in breast milk, and the documented cases
of transmission through breastfeeding indicate that the virus
was passed through the milk rather than during gestation or
the birth process. Blood from cracked nipples or breast infection
(mastitis) may also be present during breastfeeding, and may
contribute to the risk of infection.
The risk of perinatal transmission
risk at any stage can be greatly reduced by:
- Taking combination therapy during pregnancy
to reduce maternal viral load.
- Taking AZT
during labor and birth to help protect the baby while it’s
exposed to HIV in blood and cervical secretions.
- Choosing the
birth option that poses the least risk to both mother and
baby—a normal vaginal birth, or an elective cesarean
section (surgical birth).
- Administering
AZT to the newborn for up to six weeks after birth.
- Bottle-feeding
formula or breast milk from a milk bank instead of breastfeeding
or bottle-feeding your baby your own breast milk.
Prenatal Care
You’ll receive the same
prenatal care as an HIV negative woman, except for a few instances.
You’ll be working either with a prenatal healthcare provider
who is also an HIV specialist, or with an obstetrician in
addition to your regular HIV specialist.
During prenatal care, your
OB should avoid the following tests and procedures unless
they are considered medically necessary, because they are
invasive and may increase the risk of HIV transmission to
your fetus during pregnancy:
Amniocentesis:
a diagnostic test for chromosomal abnormalities like neural
tube defects and Down’s syndrome. It involves inserting
a long, very thin needle through your abdomen and into your
uterus to obtain a sample of amniotic fluid. Another screening
method that checks for alfa fetal protein (AFP) levels in
a blood sample can be done instead.
Chorionic
villi sampling (CVS): taking a sample of the chorionic
villi, tissue which will form the placenta. This is another
way to check for chromosomal abnormalities, but because it
disturbs the placental site and causes some bleeding, it’s
not as safe for your fetus as AFP testing.
Your provider may also want
to perform more ultrasounds (visualizing the fetus in the
uterus) than they would for a woman without HIV, especially
if there is a question about your fetus’s gestational
age due to irregular menstration. If this bothers you, talk
with your provider about how to keep ultrasound use at a minimum
while still getting information that will help you both decide
when an elective cesarean section can be done safely if you
decide to give birth via C-section.
Use of combination therapy
for controlling maternal HIV infection
Combination antiretroviral
therapy (also called Highly Active Antiretroviral Therapy,
or HAART) is recommended for use during pregnancy regardless
of a woman’s CD4 count or viral load. Using combination
therapy between 14 and 34 weeks in pregnancy can be helpful
in reducing your viral load, which in turn helps reduce the
risk of transmission to the fetus during gestation and also
during labor and birth. You can work with your HIV specialist
to choose a regimen from among the drugs recommended for non-pregnant
adults. Your HIV specialist may suggest a regimen that includes
AZT. If you are resistant to AZT or have experienced toxicity
with past use, be sure to tell your provider.
Avoid Sustiva! It’s
not recommended for use at any time during pregnancy due to
risk of birth defects. If you find out you’re pregnant
while using Sustiva, don’t panic! Just consult your HIV
specialist and change your regimen for the remainder of your
pregnancy. If Sustiva is working well for you, you should
be able to go back to it again after your baby is born.
For your own safety, you
should also avoid using the following meds in combination
with each other during pregnancy:
- d4T (Zerit) + ddI (Videx)
Can cause serious
and potentially fatal lactic acidosis.
- AZT (zidouvdine) + d4t (Zerit)
These don’t react well
together pharmacologically. If you’re taking Zerit
as part of your regular HAART regimen, talk with your provider
about substituting it altogether for the duration of your
pregnancy, or stopping it during labor and delivery so you
can safely use AZT prophylaxis.
If you’re already
on combination therapy when you become pregnant, most
healthcare providers will recommend that you stay on your
regimen during the first trimester of pregnancy unless you’re
too nauseous to keep your meds down. Pregnancy-related nausea
and vomiting (“morning sickness”) tends to be worst
during the first trimester for women who experience it—puking
up your pills isn’t helpful, so for some women it’s
safer to stop meds until morning sickness subsides. If you
decide to take a break from your meds, all drugs should be
stopped at the same time and then re-started at the same time
in order to reduce the risk of developing resistance (consult
your physician).
If you’ve never used
combination therapy before, many providers will recommend
waiting until after 12–14 weeks of pregnancy, unless
your viral load is very high or your health would benefit
from starting combination therapy right away. There are two
reasons for this recommendation: 1) to avoid potential side
effects such as nausea/vomiting and diarrhea at the same time
you may be struggling with morning sickness, and 2) because
the risk of medication-related birth defects (for any medication,
not just antiretrovirals) is considered highest in the first
trimester, when the fetal organ and skeletal systems are forming.
However, a woman cannot be denied therapy at any time during
a pregnancy—if you want it, you should be given it.
AZT for Fetal Protection
and Infant Prophylaxis
Even if you don’t use
any combination therapy during pregnancy, taking AZT during
the birth process and administering it to the baby after birth
will help to greatly reduce the risk of transmission. Remember,
the studies that showed AZT to be effective in reducing perinatal
transmission focused on the use of drugs during labor and
given to the baby after birth—that’s where they
found the reduction from 25% to 8%. Use of AZT and other meds
during pregnancy can help reduce the risk even more (down
to as low as 1%), but it’s almost never too late to do
something until 24 to 48 hours after the baby is born.
AZT is currently the standard
prophylactic treatment against perinatal transmission used
in the United States. If you use AZT during labor and birth,
it will be administered to you through an IV regardless of
whether you give birth vaginally or by elective C-section.
After birth, your baby will be given AZT syrup within 8 to
12 hours, and you’ll be shown how to give the syrup yourself
at home for the next six weeks.
HAART and Child Safety
It’s totally understandable
if you’re worried about what effect these powerful antiretrovirals
may have on your fetus or baby. Fortunately, studies conducted
by research entities such as the Antiretroviral
Pregnancy Registry are indicating that children born to
mothers who have used antiretroviral medications during pregnancy
do not appear to be statistically at higher risk for birth
defects than babies born to mothers who didn’t use HAART.
The preliminary results for the study following the children
who were born to women who participated in ACTG 076 (the study
that demonstrated AZT’s effectiveness in reducing perinatal
transmission) show that, after 6 years, these children do
not appear to be experiencing a greater degree of health problems
than are noted in the general population of children. However,
we can’t yet know the long-term outcomes for children
born to women who used combination therapy during pregnancy
and/or AZT prophylaxis. Research is being conducted continuously,
though, so we’re getting more and more information as
time goes on.
No one can force you to take
meds while pregnant. If you don’t want to or can’t
take meds during your pregnancy, you cannot legally be made
to take any medication on behalf of yourself or your fetus.
Right now, the use of AZT and other antiretroviral medications
in pregnancy is recommended because the known risks of pediatric
AIDS are thought to outweigh the unknown possible long-term
risks of their use during pregnancy for both mother and child.
If you have concerns about the effect AZT or other meds may
have on your child, now or in the future, discuss them with
your healthcare provider, HIV/OB specialist, or a local agency
that advocates for HIV positive people. The information in
these links may also be useful to you:
• Antiretroviral
Pregnancy Registry
http://www.apregistry.com/
• Information
About the Safety of Combination Antiretroviral Treatment for
Human Immunodeficiency Virus Infection During Pregnancy
http://www.thebody.com/cdc/pregnancy.html
• HIV/AIDS
Treatment Information Service
(800) 448-0440
http://www.hivatis.org
• AIDSinfo
website
http://aidsinfo.nih.gov
Options for Birth
If your viral load is less
than 1000 copies/ml, there is currently no evidence showing
that elective cesarean section will reduce the risk of perinatal
HIV transmission. C-section is major abdominal surgery—you
want to avoid it unless it’s considered beneficial to
you or your baby, because of the increased risk of post-operative
complications in mothers who give birth by C-section. Women
with viral loads under 1000 can consider a normal vaginal
birth to be the safest option for both them and their baby,
unless there are other factors (baby in difficult position
for birth, obstetric emergency, etc.) that necessitate C-section.
To reduce tissue damage,
extra bleeding, and infection risk during vaginal birth, your
care provider will avoid the following invasive procedures
and use of instruments unless medically indicated:
- Artifical Rupture of Membranes
(AROM—“breaking your water” with a small
instrument that looks like a crochet hook). When your bag
is intact, your baby remains protected by the amniotic fluid
and membranes that form a barrier between it and virus in
your blood and cervical secretions. Maintaining that protection
for as long as possible reduces the risk of HIV transmission
to your baby.
- Multiple vaginal exams after
membranes have ruptured. Vaginal exams are generally
done to check for progress in labor. Because there’s
an increased risk of bacterial infection each time an exam
is done, these exams will be kept to a minimum after your
water breaks.
- Internal fetal monitors and
fetal scalp tests. These cause small cuts in the baby’s
scalp, which would then be exposed to HIV in the mom’s
fluids.
- Episiotomy (a surgical
incision to enlarge the vaginal opening). Episiotomies always
cause bleeding, increasing the amount of blood your baby
is exposed to as it’s being born.
- Instruments like forceps
or vacuum extractors that necessitate episiotomies and/or
can cause vaginal tears and bleeding.
If your viral load is over
1000 copies/ml, research shows that elective cesarean section
done prior to rupture of membranes can reduce the risk of
HIV transmission by preventing contact between the fetus and
the blood and cervical secretions that are present during
the birth process (“elective” means you choose to
do it, rather than have it done for emergency reasons). C-section
after the membranes have been ruptured for at least four hours
has not shown to be statistically helpful in reducing HIV
transmission, so elective C-sections done to reduce HIV transmission
are usually performed at 38 weeks gestation (well before most
women’s water breaks on its own). Because of the increased
risk of post-operative infections in women who give birth
by C-section, your care provider may give you antibiotics
to take after the surgery.
The choice of how to give
birth is ultimately yours. Your healthcare provider should
discuss your options with you and provide their professional
opinion based on your lab tests and overall health of both
you and your fetus, but you are still the person who makes
the final decision.
What about breastfeeding?
Because there are documented
cases showing that HIV can be transmitted from mother to infant
through breastfeeding, HIV positive women are counseled to
avoid breastfeeding if safe alternatives to breastfeeding
exist. If you don’t want to feed your baby formula, you
can try to find a milk bank (an organization that collects
donated breastmilk and ships it out) in your area and use
that instead. For more information on this option, call Human
Milk Banking Association of North America, Inc. at (919) 861–4530
or on the Internet at http://www.hmbana.com.
HIV positive women living
in places where clean water and consistent supplies of safe
formulas are not available need to weigh the risks and benefits
of breastfeeding their babies. If their children are at high
risk for starvation, dehydration, and diarrhea associated
with unsafe formula-feeding, breastfeeding may be the safer
alternative even though it increases the risk of HIV transmission
to the baby. In the U.S. and Canada, HIV positive women are
largely able to safely formula-feed, and are therefore encouraged
to do so. If you live in the United States and are considered
“low income”, please know that you should also qualify
for Medicaid and WIC supplements that provide free infant
formula (regardless of your immigration status, if that’s
a concern). In many places, services may be prioritized for
HIV positive mothers, so ask your healthcare provider or case
manager for more information.
Remember!
Preventing transmission of
HIV to your baby is one very important aspect of your care,
but it shouldn’t be the only focus. Your physical and
emotional health are important for your own sake, too—and
taking care of yourself is taking care of your baby! Aside
from HIV infection, you’re just like any other pregnant
woman. Your provider should respect your decision to become
pregnant and have a baby, and should assist you in having
the healthiest and happiest pregnancy you can have. You and
your baby deserve nothing less. Congrats, and good luck!
Note: This article was
written with assistance from the Pediatric AIDS Chicago Prevention
Initiative (PACPI). For more information on PACPI’s Chicago-area
services and classes for HIV positive pregnant women, call
(773) 327-0509. Clinicians and social service providers can
call the 24-hour hotline at (312) 926-7380. Thanks to Anne
and Brenda!
Sources:
• Recommendations
for Use of Antiretroviral Drugs in Pregnant HIV-1 Infected
Women for Maternal Health and Interventions to Reduce Perinatal
HIV-1 Transmission in the United States, 8/30/2002.
• American College
of Obstetrics and Gynecology Committee Opinion Number 234,
5/00: Scheduled Cesarean Delivery and the Prevention of Vertical
Transmission of HIV Infection
• Anderson, Jean
R. MD “Cesarean Section and Perinatal Transmission”—The
Johns Hopkins HIV Report 5/99
• Elliott, Richard.
Policy & Research of the Canadian HIV/AIDS Legal Network.
Volume 5, Number 1, Fall/Winter 1999: HIV Testing & Treatment
of Children - Canadian HIV/AIDS Policy & Law Newsletter
• Guidelines for
the Use of Antiretroviral Agents in HIV-1-Infected Adults
and Adolescents, 7/14/2003
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