[back] Vaccination and pregnancy

Autism : Is There a Vaccine Connection? Part II.
around Pregnancy.

F. Edward Yazbak, MD, FAAP.  

Copyright 1999 Part 1.   Part 3. 

The Centers for Disease Control and Prevention (1,2,3,4 ) and the vaccine  manufacturers (5,6,7) have always warned against the administration of live virus vaccines during pregnancy, and shortly prior to conception.

This report describes six mothers  who received live virus vaccines and one who received a Hepatitis B vaccine during pregnancy (8) after having  received an MMR booster  five months prior to conception.

All the children who resulted from these pregnancies have had developmental problems,  six out seven (85%) were diagnosed with autism, and the seventh seems to exhibit symptoms often associated with  autistic spectrum disorders. 

Autism : Is there a vaccine connection?  Part I. Vaccination after delivery

A remarkable study from California released in March 1999, showed a 273% increase in Autism in that State in the last ten years. (9)

Shortly thereafter “Autism 99, A National Emergency” a study based on the yearly reports of  The U.S. Department of Education to Congress  described similarly impressive nationwide increases.(10)

Parents of children with autism are looking for answers to questions such as:

        What could be causing such an increase in autism in this generation of children, when autism was so rare in the past ?

        What environmental factors could be implicated?

        Could something that happened to the mothers somehow predispose their children to autism?

Many parents have reported that their children’s autistic symptoms had started shortly after they received their MMR vaccination. Was it possible the vaccine somehow reacted with antibodies which the child had received from his or her mother? And, if so, could that reaction start a chain of immune events which eventually would lead to autism?

A study was devised to investigate whether there is any association between vaccination with live virus vaccine and autism.

It was decided to target mothers who had received a live virus vaccine after the age of 16, whether or not they had an autistic child. If maternal antibodies were in any way a factor in the children’s illness, then it would be reasonable to presume that the higher the maternal titers the more likely they are to precipitate  the suspected immune reactions. Late re-vaccinations were the most liable to result in higher titers.

 Women in the target group are usually re-vaccinated for two reasons:

        They need to fulfill requirements for higher education or employment.

        They fail to develop protective antibodies in response to prior live virus vaccinations.

This second group of mothers is particularly interesting, because their inability to produce protective antibody titers may not have been due to problems with the vaccine  but rather to some immune dysfunction in the mothers themselves which could be passed to their children. 

Neither a prospective study of the general population nor credible retrospective studies are presently available and therefore members of vaccine groups and parents of children with autism were contacted via e-mail, newsletters and the internet, and asked to identify friends and relatives.

Over 280 replies were received in 120 days. Of these, about 240 entries were complete and accepted. They will be included in the main study, due to be published soon.

Seven situations where a mother was vaccinated during pregnancy are reported.

 Case Reports

 Case 1: Mother who had been fully immunized received an MMR booster in College in 1985 and another during her postgraduate training in 1988.

In 1992, she applied for employment in a hospital and was found to be measles susceptible Because she was pregnant and was afraid of the rubella vaccine component of the MMR, she requested and was given the single measles vaccine.  She was carrying twins, and one died in utero at about term. A few days later, the mother was induced (pitocin) and delivered. 

The second twin, a boy, seemed healthy at birth. He is now described by the mother as “a high need child…. vaccine affected…. and nervous system oriented”. Mother does not believe he is autistic yet describes several social and sensory constellations of symptoms which could be associated with autistic spectrum disorders. Mother has remained measles susceptible but has declined further vaccines

 Case 2: Mother received a rubella vaccine while pregnant with her first child. This boy has autism and according to the mother, “he seemed to lose some of the delayed skills that he already had” after he was given the MMR vaccine.

The mother also states : “My other two sons have a lot of traits”.

 Case 3: Mother had all three live virus vaccines as a child and a booster as a teenager. In 1984, she was given a measles vaccine to fulfill college requirements. When she found out that she was pregnant she immediately contacted the health office at the college and her own HMO physicians, who were not concerned.

Mother delivered a boy who reportedly had poor eye contact and was less responsive than expected. He was given his first MMR at age 16 months and according to the mother seemed to deteriorate after that.

By age two, he was “visibly autistic”, and the diagnosis was made at 26 months.

Case 4: Mother received an MMR booster in June 1994 five months prior to conception. She was also given a dose of hepatitis B vaccine on 9/1/94 and another on 10/6/94. Her third and last hepatitis B vaccine was administered  on 4/6/95, while she was pregnant.

She delivered a boy on 8/4/95 and breast-fed him for 8 months.  The child was “normal in the first year of life except for some digestive problems”.  He received his hepatitis B vaccines on : 9/1/95, 10/2/95 and 6/6/96 and his first MMR at 16 months of age. He started exhibiting autistic symptoms at the age  of 18 months and lost all language by the time he was 23 months old.

He has been diagnosed with autism, has tested positive for Myelin Basic Protein Antibody, and has elevated measles antibody titers. He is often severely constipated and in need of stool softeners.

A younger brother is developing normally and has been immunized routinely.

Case 5: Mother returned to college and was given an MMR vaccine in March 1990. A few days later she realized she was pregnant at the time of the vaccination. She delivered a boy in November whom she breast fed for six months and who started exhibiting autistic symptoms at the age of 10 months.

The diagnosis of autism was subsequently confirmed.

This boy received his first MMR on 12/18/91, his second on 8/18/95 and his hepatitis B series in 1998. The second child, a girl, born May 1992 is in good health and has been routinely vaccinated.

Case 6:  This mother who was born 7/18/1965 was fully immunized as a child. She delivered her first child after a 5 months gestation on  December 18, 1985. The baby weighed 2 lbs. and lived one month.

On 10/8/1987 she delivered a daughter who reportedly has an anxiety disorder.

In April 1992, the mother who was 13 weeks pregnant, was admitted to a hospital to undergo cervical banding. While in the hospital she was given a rubella vaccine booster because she was rubella-susceptible.

She delivered thirteen weeks prematurely on July 5, 1992.   The baby, a girl, weighed 1lb 11oz and remained in the Neonatal Intensive Care Unit for 115 days. She developed and was treated for sepsis, broncho-pulmonary dysplasia, and apnea.   She was also given her routine immunizations. 

On October 19, 1992 the baby had an alarming hypotonic-hyporesponsive episode following her second set of DPT, Polio and HIB vaccines.

She was discharged from the hospital on October 28, with oxygen and an apnea monitor. Growth and development were reported delayed during the first year of life. The baby was given her MMR vaccine in  October 1993, and according to the parents she started with head banging and self abusing behavior shortly thereafter. She also developed severe constipation.

A diagnosis of autism was confirmed at age 40 months.

Case 7: This Canadian mother received a rubella vaccine in 1981 when she was only a few days pregnant. She delivered a girl who appeared to be developmentally delayed starting at the age of two to three months and was mostly breast-fed for the first six months. The child received her first MMR on 7/14/1983, shortly after her first birthday and has been diagnosed with autism.


 The Centers for Disease Control and Prevention (CDC) and the vaccine manufacturer have long advised against the administration of live virus vaccines to women during and immediately before delivery. 

Seven cases of women vaccinated during pregnancy are described in this report.

Three mothers received the rubella vaccine, two the measles vaccine, and one the MMR vaccine. The seventh mother (case 4) received the recombinant Hepatitis B vaccine, but had received an MMR vaccine five months prior to conception.

 Problems with either the pregnancy or the child are reported in every instance.  If these problems are indeed related to the vaccination, then the recommendation not to vaccinate during pregnancy is justified and should be enforced.

 Six out of the seven children (85%) who resulted from these pregnancies were diagnosed with autism, and the seventh, (case 1) whose mother received a measles vaccine, exhibits symptoms which suggest autistic spectrum. This child’s twin brother was stillborn.

 One mother (case 2) may have more than one child with autism.

 A mother vaccinated with the rubella vaccine in the thirteenth week of pregnancy (case 6) gave birth to a very small premature infant who had a stormy neonatal period.

 The problems with two children ( cases 1 and 6) were apparent at delivery.(3)

 It is impossible to know in case 4 whether the hepatitis B vaccine given during pregnancy, or the MMR vaccine administered five months prior to conception, played any role whatsoever in the development of the child’s autism.

If the MMR vaccine did, then it could conceivably affect mothers vaccinated some ten, twenty or more months prior to conception and in some way contribute to the development of autism in their children.

 Selection bias alone can not explain all the reported findings.

 Another study on vaccination after delivery (11) is reported separately.

The results of the main research on the effects of maternal vaccination with live virus vaccines after age 16 will be published in March 2000.


 Seven mothers who were vaccinated during pregnancy have reported problems with the pregnancy or the resulting children.

These problems may not have happened if the mothers had not been vaccinated,

and therefore the recommendation not to administer live virus vaccines during early pregnancy and shortly before conception should be enforced more stridently.

 Consideration should be given to re-instate The Vaccine In Pregnancy Registry and to follow up the children born to mothers vaccinated during pregnancy for an extended period of time, as it is obvious that not all problems with the children were readily apparent at birth.(3)

 Six out of the seven children born to mothers vaccinated during pregnancy have been diagnosed with autism. If live virus vaccination during early pregnancy or several months prior to  conception is in any way a factor in the development of autism, then a similar relationship between autism and live virus vaccination in general should be seriously investigated by independent longitudinal large scale studies.

 Susceptible adult females do not necessarily develop protective antibodies after receiving live virus vaccine boosters.

 The administration of Hepatitis B vaccine during pregnancy should be reviewed.

 The logic of ongoing research to develop new vaccines which can be administered to pregnant women in an effort to “vaccinate two for the price of one” should be very critically questioned.

Autism : Is There a Vaccine Connection?: Part 3 Vaccination Around Pregnancy, The Sequel


1. CDC: Epidemiology and Prevention of Vaccine-Preventable Diseases, 5th Ed. page152: “Women known to be pregnant should not receive measles vaccine.    Pregnancy should be avoided for 1 month following receipt of measles vaccine   and 3 months following MMR vaccine.”

2. CDC: Epidemiology and Prevention of Vaccine-Preventable Diseases, 5th Ed.  page184: “Women known to be pregnant or attempting to become pregnant should not receive rubella vaccine. Although there is no evidence that rubella vaccine virus causes fetal damage (see below), pregnancy should be avoided for 3 months after rubella or MMR vaccination.”

3. CDC: Epidemiology and Prevention of Vaccine-PreventableDiseases, 5th Ed. page 186: “From 1971 to 1989 the Centers for Disease Control and prevention  ( CDC) maintained a registry of women vaccinated during pregnancy to determine whether congenital rubella congenital syndrome would occur in infants of such mothers.   Sub-clinical fetal infection has been detected serologically in approximately 1% to 2% of infants born to susceptible vaccinees regardless of the vaccine strain.  However, based on data collected by the CDC in the vaccine in pregnancy ( VIP) registry ( 1971-1989) no evidence of CRS has occurred in offspring of the 321 susceptible women who received rubella vaccine and who continued pregnancy to term. The observed risk of vaccine induced malformations is now 0% …..As of April 30, 1989, CDC discontinued the VIP registry.”

4. CDC: Epidemiology and Prevention of Vaccine-PreventableDiseases, 5th Ed. page 242: “Pregnant women who are otherwise eligible can be given hepatitis B vaccine”

5. PDR 1999, page 1737: “Do not give Attenuvax to pregnant females; the possible effects of the vaccine on fetal development are unknown at this time.  If vaccination of postpubertal females is undertaken, pregnancy should be avoided for three months following vaccination.”

6. PDR 1999, page 1833 : “Do not give Meruvax to pregnant females;  possible effects of the vaccine on fetal development are unknown at this time.   If vaccination of postpubertal females is undertaken, pregnancy should be avoided for three months following vaccination”.

PDR 1999, page 1834 : “It is also not known whether Meruvax can cause fetal harm.

In a ten year survey involving over 700 pregnant women who received rubella vaccine within three months before or after conception none of the newborns had abnormalities compatible with rubella congenital syndrome.”

8. PDR 1999, p. 1884 : “The (Hepatitis B) vaccine should be given to a pregnant woman only if clearly needed.”

9. Changes in the population of persons with Autism and Pervasive Developmental Disorders in    California’s Developmental Services system : 1987 through 1998. A report to the legislature.


10. Yazbak, F.E. :Autism 99 A National Emergency

 11.   Autism : Is there a vaccine connection?  Part I. Vaccination after delivery.------ F. Edward Yazbak, MD, FAAP.

 Dedicated to all the people of good will who are helping children and adults with autism.


 E-mail address : TLAutStudy@aol.com

The above may not represent the opinions of organizations to which I belong.

[VaccineWebsite]  [F. Edward Yazbak, MD]