GBS- The truth

Top 10 things about GBS of the newborn for which there is a lack of research:

1.  How many full term babies are permanently injured (not  killed) from GBS disease of the newborn?  How many experience each of the various types (deafness, learning disabilities, CP) of morbidity?

2. Do prophylactic antibiotics to GBS positive women prevent or decrease long term GBS morbidity in full term newborns (vs. mortality)?

3. The presence of GBS antibodies in the mother has been shown to be protective against Newborn GBS(10).  Women with high titers of antibodies to GBS are thought to pass on immunity to GBS to their fetus and thereby have less GBS infected babies. Smokers, drug abusers, obese and immune suppressed women produce less antibodies.  Are they more likely to have a baby with GBS disease? Is some/most/all GBS disease of the newborn associated with women with low titers of antibodies to GBS?

4. There is only one published study asking whether pregnant women who culture GBS positive in urine, also culture positive in rectovaginal culture.  Of 1036 assymptomatic women who underwent routine urine culture in pregnancy, 10.7% had GBS in their urine, of those 70% of those had <10,000 CFU (colony forming units) and 30% had >10,000 CFU which is considered highly colonized. Of the 111 women who had GBS in their urine (bacteriuria), 40% cultured negative for GBS on rectovaginal swabs. Women who were heavily colonized in urine were no more likely than those lightly colonized in urine to have  positive rectovaginal cultures. (16)

Approximately 11% of women colonized positive for GBS in urine and their healthy babies culture positive for GBS than other babies, however no one has ever documented higher rates of GBS DISEASE associated with maternal GBS bacteriuria. GBS in urine has been associated with chorioamnionitis- uterine infections in the mother- which is most closely associated with prolonged labors, as well as frequent vaginal exams, internal monitoring, prolonged ROM, cesareans, and teenage pregnancies,  but to date not documented to be associated with GBS disease of the newborn.

There are many claims that antibiotics during pregnancy given to women wiht GBS bacteriuria can prevent preterm birth, but this data is confounded by studying high risk populations. A RCT study contradicts this claim, found that women with GBS bacteriuria, additional exposure to antibiotics is associated with an increased, not decreased, risk of preterm birth.  In this study the rate of preterm birth for women with bacteriuria was 16% and without GBS bacteriuria was also 16% and 28% among women with GBS bacteriuria who received antibiotics. (17)  All three rates reflect outcomes only seen in extremely high risk populations. Healthy, well fed populations,   the preterm rate is 7%.   Asymptomatic  GBS bacteriuria may not have a role in preterm birth but rather may be a marker for low socioeconomic status which is associated with low birth weight. (18) The quality of even the best studies on asymptomatic bacteriuria in pregnancy is poor. (18)

The unanswered question is: Do heavily colonized full term women have more GBS newborn disease or perhaps less newborn GBS due to higher titers of antibodies against GBS that they pass to the fetus?  Are women who heavily colonized  with GBS, whether in urine or vagina,  more likely or less likely to have babies with GBS disease?  We dont know.

Does giving oral antibiotics to pregnant women with asymptomatic GBS bacteriuria decrease or increase the occurrence of GBS disease of newborn?

5. 50% of GBS disease of the newborn occurs to babies of women with the following risk factors: Premature, IUGR, LBW, ROM > 18 hours, and fever.  The other 50% occurs to babies of women without those risk factors.  Of those women, how many had ROM between 2 and 17.9 hours?  Since prolonged ROM is known to increase the risk of GBS disease, how would eliminating AROM affect the occurrence of GBS disease of newborn?

Is there a difference in the GBS disease among women with impressive, flowing ROM which fills up pads quickly and women who have a high leak that is leaks 1 to 2 cc per hour?  Is a high leak a risk of newborn GBS at all?

6. On page 11 of the 2002 CDC protocols appears one of several unqualified statement “GBS can cross intact amniotic membranes.”   A study of 550 babies born to GBS positive women, by CS without ROM, and without prophylaxis, demonstrated not a single case of GBS disease, where one would expected 5 sick newborn if GBS crossed membranes, supporting the theory that GBS either never crosses membranes. In vitro study has not been able to demonstrate GBS crossing membranes, even at concentrations of 1,000,000,000 CFU.  (20) Further investigation into how GBS could cross intact membranes demonstrated that GBS failed to invade amnion cells under a variety of assay conditions (21) and fetal membranes demonstrated an inhibitory effect on GBS. (22).  Cases of  colonized infants born by CS in the absence of ruptured membranes could be due to any number of other vectors other than the mother that come in contact with the baby.

7. Over 6 vaginal exams significantly increased rates of GBS disease(15).  Scalp electrodes double the risk of GBS colonization of amniotic fluid (19)

In my practice, with restricted AROM and Vaginal exams and no scalp electrodes, 3% of births the baby’s head comes out in the sac and never makes direct contact with the uterus, cervix or vaginal walls at all. How would restricted AROM, Vaginal exams and scalp electrodes affect GBS disease rates?.among low risk women? Among high risk women?

8. When does GBS cause disease? 99% of babies colonized with GBS, dont get GBS disease.  99.99% of women colonized with GBS, dont get GBS vaginitis. Why does GBS sometimes attack and sometimes live in ecological balance?   Why is GBS present in 2-3 times as many women in the USA than in Ireland, Cambodia, Taiwan, Philippines or Africa?  (11)  Why is long term (over 6 months duration) Symptomatic GBS Vulvovaginitis becoming more common in the western world? (12)

9.  How does GBS inhibit lactobacillus growth?

10. How many newborns will die of GBS disease in 10 years? 20 years? 40 years?

In the presence of so many unknowns, current protocols reflect an bias to take action in the presence of a lack of appreciation or humility for the complex habits of GBS and no consideration of the next generation of newborns.

1. Ohlsson A, Shah VS. Intrapartum antibiotics for known maternal Group B streptococcal colonization. Cochrane Database of Systematic Reviews 2009, Issue 3. Art. No.: CD007467

 

2. Yancey MK, Schuchat A, Brown LK, Ventura VL, Markenson GR.The accuracy of late antenatal screening cultures in predicting genital group B streptococcal colonization at delivery. Obstet Gynecol 1996;88:811–5.

 

3. Itakura A.Kurauchi O Morikawaa S, Matsuzawab K Mizutania S, Tomodaa Y. Variability of peripartum vaginal group B streptococcal colonization. International Journal of Gynecology & Obstetrics 55 (1996) 19-22.S
4. Tamerou Asrat, et.al.The accuracy of late third trimester antenatal screening for group B streptococcus in predicting GBS colonization at delivery American Journal of Obstetrics and Gynecology, Volume 195, Issue 6, Supplement 1, December 2006, Page S40
5. Chu YW, Tse C, Tsang GK, So DK, Fung JT, Lo JY. . Invasive group B Streptococcus isolates showing reduced susceptibility to penicillin in Hong Kong. Antimicrob Chemother. 2007 Dec;60(6):1407-9.

6.  Joachim A, Matee MI, Massawe FA, Lyamuya EF. Maternal and neonatal colonisation of group B streptococcus at Muhimbili National Hospital in Dar es Salaam, Tanzania: prevalence, risk factors and antimicrobial resistance. BMC Public Health.;2009: 9:437.

7. Klevens RM, Morrison MA, Nadle J, et al.Invasive methicillin-resistant Staphylococcus aureus infections in the United States. JAMA. 2007 Oct 17;298(15):1763-71.

8. Appelbaum, P. C. 1992. Antimicrobial resistance in Streptococcus pneumoniae: an overview. Clin. Infect. Dis. 15:77-83.

9. Jacobs, M. R., S. Bajaksouzian, A. Zilles, G. Lin, et al. 1999. Susceptibilities of Streptococcus pneumoniae and Haemophilus influenzae to 10 oral antimicrobial agents based on pharmacodynamic parameters: 1997 U.S. Surveillance study. Antimicrob. Agents Chemother. 43:1901-1908.

10. Walsh CT Fischbach MA New ways to squash superbugs. Scientific American, 2009. 301:32.

11. Whitney CG. et.al.The International Infections in Pregnancy Study: group B streptococcal colonization in pregnant women. The Journal of Maternal–Fetal and Neonatal Medicine 2004;15:267–274.

12. Cohain, JS. Long term Symptomatic GBS Vulvovaginitis – 8 cases resolved with freshly cut garlic. European Journal of OBGYN Reprod Biology. 2009;146(1):110-1.

13.   Lin FY, Troendle JF. Hypothesis: Neonatal respiratory distress may be related to asymptomatic colonization with group B streptococci. Pediatr Infect Dis J. 2006 Oct;25(10):884-8.

14.  McKeever TM, Lewis SA, Smith C, Hubbard R. . The importance of prenatal exposures on the development of allergic disease: a birth cohort study using the West Midlands General Practice Database. Am J Respir Crit Care Med. 2002 Sep 15;166(6):827-32.

15.  P T Heath,1 G F Balfour,1 H Tighe,1 N Q Verlander,2 T L Lamagni,3 A Efstratiou Group B streptococcal disease in infants: a case control study. Arch Dis Child 2009 94: 674-680.

16. Centelles-Serrano MJ, Pérez-Moreno MO, Llovet-Lombarte MI, Cortell-Ortolá M, Jardí-Baiges AM, Buj-González JI.Effectiveness of systematic investigation for Group B Streptococcus in urine samples to identify colonized pregnant women. Enferm Infecc Microbiol Clin. 2009 Aug-Sep;27(7):394-8.

 

17. Anderson BL, Simhan HN, Simons K, Wiesenfeld HC. Additional antibiotic use and preterm birth among bacteriuric and nonbacteriuric pregnant women. Int J Gynaecol Obstet. 2008;102(2):141-5.

 

18 .  Smaill F, Vazquez JC. Antibiotics for asymptomatic bacteriuria in pregnancy. Cochrane Database Syst Rev. 2007; 18;(2):CD000490.

 

19. Keski-Nisula L, Kirkinen P, Katila ML, Ollikainen M, Saarikoski S. Cesarean delivery. Microbial colonization in amniotic fluid.J Reprod Med. 1997;42(2):91-8.

 

20. Kjaergaard N, Helmig RB, Schønheyder HC, Uldbjerg N, Hansen ES, Madsen H. Chorioamniotic membranes constitute a competent barrier to group b streptococcus in vitro. Eur J Obstet Gynecol Reprod Biol. 1999 Apr;83(2):165-9.

 

21. Winram SB, Jonas M, Chi E, Rubens CE. Characterization of group B streptococcal invasion of human chorion and amnion epithelial cells In vitro. Infect Immun. 1998 Oct;66(10):4932-41.

 

22. Kjaergaard N, Hein M, Hyttel L, Helmig RB, Schønheyder HC, Uldbjerg N, Madsen H. Antibacterial properties of human amnion and chorion in vitro. Eur J Obstet Gynecol Reprod Biol. 2001;94(2):224-9.

 

23. Centers for Disease Control and Prevention (CDC). Trends in perinatal group B streptococcal disease – United States, 2000-2006. MMWR Morb Mortal Wkly Rep. 2009 Feb 13;58(5):109-12.

 

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Q: I have really enjoyed reading your column on JPost.com, and have a question for you. How many ultrasounds are safe for a baby? Has there been any real research on the effects in this area? I’ve heard Israel does many ultrasounds comparatively, and would like to gather more information before going along with all the doctor says. Thank you so much for your help! SS

A: : Thank you for asking this important question. Ultrasounds are ultra-high frequency sound waves emitted by a transducer that is moved over the mother’s abdomen, producing a picture of the baby in the uterus. In Israel this diagnostic test is done routinely 2 – 4 times during the pregnancy, though some doctors (almost always those who have ultrasound equipment in their offices) perform ultrasounds at every prenatal visit.

Most ultrasound machines use pulses of ultrasound that last a fraction of a second. The time between the pulses is used to interpret the scan that returns to the machine. Doppler techniques used in specialized scans and fetal monitors use continuous waves of ultrasound.

The World Health Organization maintains that routine ultrasound testing has not been sufficiently evaluated to let the practice go unquestioned. The primary concern is the effect of ultrasound waves on fetal brains. The Federal Drug Administration (FDA) of the USA states, “Ultrasound is a form of energy and, even at low levels, laboratory studies have shown it can produce physical effects in the tissue, such as jarring vibrations and a rise in temperature.” They maintain that prenatal ultrasounds can’t be considered completely innocuous.

It is important to differentiate between selective and routine use of ultrasound. The time taken to do the scan, the type of equipment used and the experience of the technician also need to be examined. Ultrasounds can provide important information in specific clinical situations, such as if a fetus is alive or dead, to predict whether a pregnancy will continue after a threatened miscarriage and gestational age (particularly when this is done in the first or early second trimesters). Ultrasounds can also often diagnose a malformation and can be used with additional testing such as amniocentesis or chorion villus sampling and are used to assist procedures such as a cervical cerclage or external cephalic version (turning a breech baby). It can assess fetal growth in the second half of the pregnancy and can locate the position and health (grade) of the placenta. It can be used to confirm a suspected multiple pregnancy, assess the amount of amniotic fluid (this can vary based on the time of day and the amount of fluid ingested) and determine the fetal position (this can be assessed manually by a skilled practitioner).

Ultrasound waves affect the tissues in two ways. Firstly, the sonar beam heats the highlighted area and, secondly, the small pockets of gas that exist in the tissue being scanned vibrate and then collapse (an effect known as cavitation). Many animal studies have indicated that the effects of ultrasound waves can be harmful to the central nervous system.

Human studies have shown that ultrasound testing during pregnancy shows possible adverse effects including “premature ovulation, miscarriage or pre-term labor, low birth weight, poorer condition at birth, perinatal death, dyslexia, delayed speech development and less right-handedness. Non right-handedness (left-handedness and ambidexterity) is a consistent finding in many studies and is, in other circumstances, seen as a marker of damage to the developing brain.” (“Gentle Birth, Gentle Mothering” by Dr. Sarah J. Buckley, One Moon Press, 2005).

Many physicians claim that the benefits of ultrasound outweigh the risks, but a large randomized trial of 15,151 pregnant women, conducted by the RADIUS Study Group, found that in low-risk pregnancies, high-risk subgroups and even in cases of multiple gestations or major anomalies, the use of ultrasound did not result in improved outcome in the pregnancies (Ewigman, B.G. et al 1993 “Effect of Prenatal Ultrasound Screening on Perinatal Outcome” N. Engl. J. Med. 329 (12); 821-27). Some suggestion has even been made connecting frequent use of ultrasound in pregnancy with the steep increase in autism (“Questions about Prenatal Ultrasound and the Alarming Increase in Autism” by Caroline Rodgers in Midwifery Today, Winter 2006, # 80).

An important consideration in the decision to have ultrasound testing in pregnancy is the mother’s emotional attitude. Some women are eager to “see” their babies in utero and are more relaxed knowing that the baby is developing normally. This is often a positive step in developing the bond between the mother and her baby. Other women, however, feel that ultrasound is an invasion of the baby’s privacy and feel that the magical nature of the pregnancy is being medicalized.

Another consideration is what you plan to do with the information provided by the ultrasound. When used for diagnostic purposes, ultrasounds can lead to life-saving fetal surgery or can prepare specialists to be on hand at the birth to provide immediate care for a specific problem. However, when used routinely, ultrasounds can often be a cause for unnecessary anxiety without any benefit. Ultrasounds often pick up inconclusive abnormalities in late pregnancies when nothing can be done about them and the mother remains anxious until and frequently even after the birth which can adversely affect her bond with her baby.

http://well.blogs.nytimes.com/2012/07/02/fear-makes-labor-longer-study-finds/?src=recg

Fear Makes Labor Longer, Study Finds

By NICHOLAS BAKALAR