Here is the situation: there was a large study that recorded all births in New York City from 1995 to 2003 and now people are analyzing the data. This data is presented in short form at national specialist meetings - called abstracts or posters - this week at the Annual Meeting of the Society for Maternal Fetal Medicine.
Out of 800 abstracts and posters, two of them have specifically made the news. Abstract #13 and Abstract #474 headed by Dr. Erika Werner from Johns Hopkins. You can go to the Society for Maternal Fetal Medicine meeting site at http://www.eventkaddy.com/smfm2012/, click on the top option above the cowboy boots and then search 'Werner' or look in posters to find those poster/abstract numbers.
(In case you were wondering, there are also abstracts at the same meeting that says there is no difference in survival/complications from C-sections, and Dr. Werner's group published a paper in December 2011 using the same data on term children that suggested C-sections are PERFECTLY safe for term children and the forcep method might be superior in some cases.)
About the study, looking at the data, in preterm infants from single babies born at 25-34 weeks gestation, they compared the Apgar score at 5 minutes, the risk of brain hemorrhage, and the risk of respiratory distress syndrome between vaginal and c-section births. All of those things are VERY short term outcomes. (If the Apgar score is zero at 10 minutes, that is bad but it means very little otherwise.) They also excluded all of the babies with congenital abnormalities, birth weight below 500 grams, and need for vacuum or forceps. They used some statistical techniques to take into account ethnicity, diabetes, blood pressure, maternal education, insurance status, and pre-pregnancy weight.
So what did they find?
Csections and vaginal deliveries of these 'healthier' premature infants, small or normal size for gestational age (SGA/AGA), had somewhere between 1.7-2 times higher risk of respiratory distress syndrome. Apgar scores corrected to being the same, seizures, brain bleeds, and infection occurred at the same rates.
What does that mean?
It means that a premature 'healthy' premature child in their age range has a double risk of needing oxygen compared to a vaginal delivery of the statistically/demographically same child delivered vaginally. For example, if the risk of needing oxygen is normally 1%, it is 2% with a c-section. If it were 10%, it is somewhere between 17-20% of needing oxygen. I say 'needing oxygen' because that the most typical cause in a premature infant for getting diagnosed with 'respiratory distress.' Other things you might have heard of that require oxygen, transient tachypnea of the newborn, meconium aspiration, persistant pulmonary hypertension all are disorders of term infants which pretty much leaves respiratory distress and congentital abnormality as your other causes of oxygen requirement in a preterm infant.
Okay, so c-sections are dangerous, just like they said on the Today Show!
Actually, they left out a TON of information on what this means and then tried to talk about C-sections in general being bad for full term babies. Typical alarmist talk-show hosts. The study they are referring to addresses none of these things. It only looks at those babies very narrowly and only from viewing annonymous hospital records. Note that the author is from Johns Hopkins in Baltimore, not New York City. All of the information they used can be pulled from the electronic medical record of the delivery check-boxes. It has nothing about prenatal care or clinical situation that caused each C-section.
That is important? YES! Here is why -
C-section Scenario: The mom is 28 weeks pregnant, has a fever, and her water just broke. The baby on the monitor is showing bizarre patterns that may mean it is not getting enough blood/oxygen from mom. Every hour her water is broken this early, the risk of life-threatening infection for the mom and baby increases. The OB gives the mom a dose of steriods to mature the baby's lungs, puts the mom on antibiotics, gives some meds to hold off labor, and hopes the baby can wait 24-48 hours which you need for the steroids to take affect for the baby.
16 hours after the dose of steriods, the baby starts showing even more abnormal patterns on the monitor. Mom's heart rate and fever are up too. The OB knows the mom and baby are on the border of being deathly ill and has to make a decision. Labor has not started yet, so she can induce the mom and hope the baby will deliver in the next 2-3 hours. Of course, it could take 24 hours you cannot tell how long it will take. The OB has no control of exactly what point the baby passes from being someone that can be saved to someone that cannot. It could be 10 minutes, 3 hours, 12 hours. The baby has to survive the labor and delivery which will last an unknown time. The longer they wait, the higher chance the mom has of bleeding to death during delivery as her blood may not clot properly due to the infection, despite maximum antibiotics.
If the OB performs a C-section, she/he can get the baby out in the next 10 minutes. Jane MD will arrive with her delivery team and all the supplies to resucitate the infant. In fact, the OR has the best equipment for preterm delivery and even an emergency C-section has 5 minutes warning. That means Jane MD will have the life and lung saving surfactant in the OR during the delivery, which will make the baby's immature lungs be able to pass oxygen. The goal is to get the baby the surfactant before 10 minutes of life - most babies under 30 weeks will need to be intubated for respiratory support no matter what and require oxygen. If the baby got steroids and surfactant at the right times, the time on the ventilator with oxygen is often much shorter. (Did you notice that the 5 minute Apgar isn't concerning me at all?)
Vaginal delivery scenario: The mom is 28 weeks pregnant and her water just broke. The baby looks fine on monitor. The OB gives the mom steroids and antibiotics. The OB uses different drugs to prevent labor from starting a full 48 hours, but when the contractions start, they can't be stopped. The mom still doesn't have a fever and the baby looks good on monitor. It takes 4 hours of labor for the baby to be born. Jane MD is called in time and is able to give surfactant before 10 minutes of life and the baby does not spend a long time on the ventilator.
These two babies and moms were very similar, but the clinical situations were very different. The c-section scenario was much sicker. If the vaginal birth baby had started to look bad on the monitors, she would have had a c-section too. Obviously, some women will come with a 28 weeker and deliver immediately vaginally without antibiotics or steroids but those women are also often sicker and will often receive an immediate emergency c-section. The study didn't tell us if the c-section babies were more likely to have steroids, which prevent respiratory distress because the study did not examine that as an outcome.
Basically, it all comes down to clinical situation. C-sections can be done quickly and remove a baby that is in distress almost immediately. Vaginal birth is much less predictable, so C-sections are going to be favored for sicker, premature babies. Thus is is not surprising their oxygen needs/respiratory distress issues will be higher. The study is looking at the past without having any control of what decision was made or why it was made.
I am not saying that vaginal deliveries for preterm babies can never be safe. If the baby is stable, they are very safe. If the mom or baby is not stable, it is important to be in as control as possible of the situation and get the baby out ASAP. Would you want to have a conversation with your doctor like this, "You/Your baby is showing bad signs of illness, let's just wait a few hours to see if you can delivery vaginally."
To make matters worse, the Today show medical correspondent then tries to link ashthma to respiratory distress syndrome - which it is not. Smoking, African American descent, low socio-economic status, multiple respiratory infections, and genetics are linked to asthma. Not respiratory distress syndrome. Asthma rates are going up in general on all populations so also NOT related to respiratory distress.
Even worse, she goes on to suggest that women don't want to 'feel' the pain of labor and that is why the C-section rate is so high. She says everyone should be getting a VBAC (vaginal birth after C-section). She knows NOTHING! VBACS can be very safe if you are a good candidate - had only 1 c-section, not with high blood pressure, not overweight, not diabetic, not carrying multiples, not getting an induction, had good prenatal care, are white, and have an OB that will be in the hospital 24-7 to change you over to a C-section if something goes wrong. (There is a 1% chance the uterus will rupture and without prompt C-section and management, both the mom and baby could die).
Don't let the Today Show scare you. If you have a question about C-sections or what they showed on TV today, ask your OB/GYN. If you want to know what pediatricians think, ask them or comment on my blog.
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