Saturday, January 31, 2009
Take for example this week's highly publicized U.S. report, 'Severe Obstetric Morbidity in the United States: 1998-2005', by EV Kuklina et al. They found that the "prevalence of delivery hospitalizations (per 1,000) complicated by at least one severe obstetric complication increased from 0.64% (n=48,645) in 1998-1999 to 0.81% (n=68,433) in 2004-2005." And that
Perception of risk - actual increase versus percentage increase
Clearly, these numbers in real terms - especially when you consider that they take into account ALL delivery complications (including emergency cesareans) - are relatively small (less than 1%), but what many media reports concentrated on was the '% increase' number, which of course looks a lot higher - and riskier - when reported without the 'per 1000' figures.
For example, renal failure increased "by 21% (from 0.23 to 0.28), pulmonary embolism by 52% (0.12 to 0.18), adult respiratory distress syndrome by 26% (0.36 to 0.45), shock by 24% (0.15 to 0.19), blood transfusion by 92% (2.38 to 4.58), and ventilation by 21 % (0.47 to 0.57).
The authors conclude that: "Rates of severe obstetric complications increased from 1998-1999 to 2004-2005. For many of these complications, these increases were associated with the increasing rate of cesarean delivery.
But is cesarean surgery the reason for greater severe morbidity - or are other factors to blame?
Adding to a growing body of evidence on this subject, a Scottish review this month by A Poobalan et al, 'Obesity as an independent risk factor for elective and emergency caesarean delivery in nulliparous women - systematic review and meta-analysis of cohort studies' tells us that cesarean delivery "risk is increased by 50% in overweight women and is more than double for obese women compared with women with normal BMI."
And in 2003, KS Joseph et al's Canadian study, 'Changes in maternal characteristics and obstetric practice and recent increases in primary cesarean delivery', which set out to "estimate the contribution of changes in maternal characteristics (namely, age, parity, prepregnancy weight, weight gain in pregnancy, smoking status) and obstetric practice (namely, labor induction, epidural anesthesia, delivery by an obstetrician, midpelvic forceps delivery) to recent increases in primary cesarean delivery rates", concluded that "Recent increases in primary cesarean delivery rates are a consequence of changes in maternal characteristics. Obstetric practice, which has altered due to changes in maternal characteristics and concerns related to fetal and maternal safety, has also contributed to increases in primary cesarean delivery."
Specifically, the researchers noted a 14% increase in cesarean deliveries for dystocia, 24% for breech, 21% for suspected fetal distress, 47% for hypertension, and 73% for miscellaneous indications between 1988 and 2000. Importantly: "Adjustment for maternal characteristics reduced the temporal increase" in cesarean rates from 21% to 2% [and] Additional adjustment for obstetric practice factors further reduced period effects."
The future of cesarean rates
A review by Rebecca Simmons, MD., 'Perinatal Programming of Obesity', published in the U.S. in October 2008, reminds us that the prevalence of obesity "has risen dramatically over the last decade [and a] number of epidemiological studies have shown that there is a direct relationship between birth weight and BMI in childhood and in adult life." I would suggest that with no sign of a decline in obesity rates (in fact, quite the opposite) and with women continuing to have their babies later and later in life, we are not going to see any significant reduction in primary cesarean rates at all, and we need to be very careful about implementing strategies to drastically reduce them since this will result in greater morbidity and mortality for these women and their babies.
Monday, January 26, 2009
When I saw this new study from Canada by M Tanaka et al, 'ED95 of phenylephrine to prevent spinal-induced hypotension and/or nausea at elective cesarean delivery', it reminded me of my own experience during the birth of my daughter in 2007. The anesthetist had warned me prior to the start of surgery that I may experience some nausea, and to let him know if I did as he would be able to administer something for it. Well, I did, and he did, and in truth, I have no idea what the drug was, but I felt better almost immediately.
For those of who would like to be able to discuss this occurence of nausea and its treatment during your cesarean surgery in more detail (with your OBGYN or anesthetist), you might find this study interesting. It set out to "determine the 95% effective dose (ED95) of phenylephrine by intermittent i.v. bolus, to prevent spinal-induced hypotension and/or nausea at elective cesarean delivery" and involved 50 patients undergoing elective cesarean delivery under spinal anesthesia.
The study results
"The ED95 of phenylephrine was estimated as 159 mug (95% confidence interval: 122-371 mug), although the largest dose given in the study was only 120 mug. Hypertension (systolic blood pressure >120% of baseline) was observed in 14 cases, immediately after intrathecal injection and prophylactic phenylephrine administration in all cases." The authors conclude that the "safety of this dose warrants further studies."
Blood loss following surgery
This second study from Iran, 'Efficacy of tranexamic acid in reducing blood loss after cesarean section' by L Sekhavat et al, was conducted on 90 primiparas divided into two groups who underwent cesarean delivery. "The study group, 45 women, received tranexamic acid immediately before CS, whereas the control group, 45 women received placebo" and then blood loss volume for each group was measured from the end of surgery to 2 hours postpartum.
The authors conclude that: "Tranexamic acid statistically reduces blood loss from end to 2 h after CS and its use was not associated with any side effects or complications. Consequently, tranexamic acid can be used safely and effectively to reduce bleeding resulting from CS." My second baby is due shortly, and a cesarean delivery is planned, so I will certainly be asking my doctor about whether the findings in this study are relevant to my potential recovery experience.
Thursday, January 22, 2009
The researchers conclude that "Vaginal birth is not associated with POPQ stages III and IV prolapse, but it is associated with an increase in POPQ stage II defect."
Birth risk/benefit analysis
This study demonstrates that there IS a link between vaginal delivery and subsequent pelvic organ prolapse (POP), and is in fact one of a number of studies to do so. Unfortunately, women planning vaginal deliveries are not always advised of this risk. In fact, in the U.S. December 2006 'Pelvic Organ Prolapse Topline Summary by ICR', an Ethicon Women's Health & Urology survey found that among the total female population age 21 and older, only 1 in 5 (19%) are even aware that such a female condition exists.
Furthermore, 2 out of 3 (68%) women diagnosed with POP were not aware of its existence before experiencing symptoms, and the majority (81%) of women who have given birth did not receive education about the relationship between a vaginal delivery and possible pelvic organ prolapse from their OB/GYN.
Are we truly informing women of the risks associated with vaginal delivery?
"Only 15% of women who have given birth report that their OB/GYN educated them about the relationship between a vaginal delivery and the condition [yet the] greatest risk factor for pelvic organ prolapse is a vaginal delivery, at any age."
Sze and Hobbs analyzed 458 nulliparas (first-time mothers) and 892 multiparas, including 272 with one, 299 with two and 321 with at least three term vaginal deliveries, and found that the "prevalence of POPQ stage II defect among nulliparas and multiparas that had one, two, and at least three term vaginal deliveries was 25% (119/458), 50% (137/272), 66% (198/299), and 69% (220/321), respectively (p<0.001), p="0.618)." style="font-weight: bold; color: rgb(0, 0, 102);">
In releasing the figures, the Utah Department of Health is reported as saying that 14% is "lower than expected compared to national figures. But the tears can cause long lasting problems, including painful sex and fecal incontinence."
The article also cites comments from Ashley Nelson, a women's health physical therapist in Salt Lake City, who says: "It's hush, hush. Most people don't talk about this". She sees women seeking help to strengthen their pelvic floor muscles or who have irritated or damaged nerves because of scarring from tearing or subsequent care. "A lot of times they may sew them up too tight [and women experience] pain [from] penetration. Or just the way they've been sewn back up - it's irritated nerves and [they] constantly have pelvic pain," she said.
14% is the risk for SEVERE tears - many more women experience "minor tearing"
"...While minor tearing during delivery is common, the health department report focused on third and fourth-degree lacerations, which extend from the vagina to the anus. Using instruments increases the risk of severe tears. So does delivering large babies or having an episiotomy, a surgical cut between the vagina and anus. Doctors use instruments if the baby's heart beat drops dangerously or if the mother is worn out from pushing.
Some Utah hospitals have a 29% vaginal tear rate
"Utah hospitals' rate of vaginal tears range from 4.5 percent at Ogden Regional Medical Center to nearly 29 percent at Uintah Basin Medical Center in Roosevelt. "
The full report, '2007 Utah Hospital Comparison Report: Maternity and Newborns', can be accessed here.
Wednesday, January 21, 2009
He says: "The article gives the impression that Caesarean section is detrimental to the health of the baby and should not be resorted to at all. Our greatest concern is that mothers may refuse to give consent when a Caesarean section is indicated in times of emergency after reading the article."
He continues: "In any operative delivery or, for that matter, in any operation, the benefits from the operation must be weighed against the short-term and long-term risks of the operation. Perhaps, one of the long-term risks to a baby born by Caesarean section may very well be a higher incidence of asthma but this must be balanced against the immediate and long-term risks to the baby when there is delay or no intervention by Caesarean section.
We do not want a baby to be forever mentally handicapped for fear of a higher risk of asthma.
The study quoted in the report, from the Dec 3 issue of the medical journal Thorax, showed that Dutch children born by Caesarean section were 80 per cent more likely to develop asthma by the time they are 8 years old. This study, together with another Norwegian study published in June last year in the Journal of Pediatrics, has shown an increased risk.
However, previous studies have shown conflicting evidence. More prospective, multi-central studies from many different countries need to be done before this risk is accepted into evidence-based practice. More importantly, other aspects such as failure to breast-feed a baby after a Caesarean section need to be considered.
Nevertheless, the increase in Caesarean section rates in the past couple of decades cannot be denied. It has always been an important and heavily debated topic of discussion in practically every obstetrics conference all over the world. The reason for this is complex and every attempt has been made by the fraternity to reduce this rate. But its judicious use has saved many a mother and baby."
I agree with a great deal of what Dr Baskaran says, but it would be interesting to learn more about his views on planned cesarean delivery with no medical indication. He does mention above that "every attempt has been made by the fraternity to reduce this [cesarean] rate" and it concerns me that women making legitimate decisions to choose one set of birth risks and benefits over another may be not be supported in Malaysia. I only hope that this is not the case.
Friday, January 16, 2009
Dr. McGlynn makes the valid point that "information about choices to make as pregnant women enter into labor and delivery is not... straightforward." He says, "Questions about the birth process and whether to accept pain medication during labor or bypass labor altogether and have an elective caesarian section are very personal choices."
His advice?: "With so many decisions to make, pregnant women should be comfortable enough with their obstetricians to make sure they [are] even writing questions down in advance. After all, a healthy mom and a healthy baby is everyone’s ultimate goal."
I completely agree with Dr. McGlynn's advice; in fact, this is exactly what I did ahead of my visits with my OBGYN. I read as many medical studies on cesarean risks and benefits as I could find, and was fortunate enough to have a doctor who was willing to answer all my questions and help me to understand my own individual health risks. Pregnancy and childbirth are not without risk, but understanding and feeling comfortable with the decisions you make has been shown in studies (10,11,13,15) to help increase women's likelihood of post-birth satisfaction.
This type of comparative trial has been criticized for being unethical and/or unfeasible in the past (by other researchers and doctors), but this latest research from Australia isn't all negative. The authors begin by stating that "Elective caesarean section is controversial in the absence of compelling evidence of the relative benefits and harms compared with vaginal delivery. A randomised trial of the two procedures to compare outcomes for women and babies would provide the best quality scientific evidence to confirm this debate but it is not known whether such a trial would be feasible."
They set out to ascertain what proportion of pregnant women and clinicians would participate in a hypothetical randomised controlled trial comparing the two delivery methods by asking pregnant women (via interviews) and midwives, obstetricians, urogynaecologists and colorectal surgeons (via a mailed, self-administered questionnaire).
How many support a hypothetical trial?
Out of 100 pregnant women, 84 midwives, 166 obstetricians, 12 urogynaecologists and 87 colorectal surgeons, 14% of pregnant women and 31% of clinicians indicated that they would participate in a randomised controlled trial.
Is this enough?
14% is a very low number, but I would be interested to learn whether the 100 women questioned already had a birth plan in mind, and also whether the hypothetical trial (as explained to them) meant that they would get to choose between each delivery or whether that delivery method would be allocated to them. These factors are crucial and could make a huge difference to the final percentage tally.
31% is almost a third of clinicians saying 'yes', and this is actually a sizeable proportion. If nothing else, it indicates that aversion to such a trial is no longer in the minority.
The number of healthy women electing to have cesarean deliveries with no medical indication is reportedly low. However, these women do exist and their health outcome data is on record at hospitals (especially private hospitals) throughout the world. If we could gather the data available for some or all of these deliveries, this would go a long way to informing risk and benefit analysis as compared to planned vaginal deliveries in healthy women (the data of which is readily available at numerous large hospitals).
In 2003, doctors in Australia asked the question 'Should obstetricians support a 'term cephalic trial'? (Robson S, Ellwood D. Aust N Z J Obstet Gynaecol. 2003 Oct;43(5):341-3.) In subsequent media reports, they were quoted as saying:
Dr Robson: 'What a disaster it would be if it was found elective cesarean was safer than vaginal birth.'
Dr Ellwood: 'There is an increasing trend towards elective cesareans, and there have been discussions over the last couple of years about mounting the so-called term-cephalic trial, which would be a randomised trial comparing cesarean versus planned vaginal birth for women having their first babies. We're concerned that the impact of such a trial could well be quite far reaching, and that it needs to be well thought through before such a trial is mounted.' [The reporter continued:] His fear is that if caesarean sections were found to be safer in such a trial, doctors and patients might feel compelled to go that way.
Pregnancy is risky; childbirth is risky. It is a woman's progagative to decide which set of delivery risks (vaginal or cesarean) is most tolerable to her.
The autors found an incidence proportion of DVT post cesarean delivery of 0.5% and say this is the largest study to date that uses Doppler compression ultrasound to diagnose DVT in women after cesarean deliveries.
The research is certainly worth a read, but I've highlighted some of the interesting points made by the researchers in the 'Comment' section of their presentation:
*A Swedish prospective study found an incidence of DVT post cesarean delivery at 1.8% using impedance plethysmography, which is known to have high false positive rate compared to Doppler ultrasound. However, four other studies using Doppler ultrasound did not find any DVT in their cesarean delivery population... [many more studies are cited]
*This incidence of post cesarean delivery DVT is much lower than that reported among general surgical patients... This disparity between general surgical patients and patients undergoing CD may be due to many factors. First, patients undergoing CD are generally younger. This is still true even though 20% of our population would be described as “advanced maternal age” for being over 35 years old. Age is both an independent risk factor of VTE and is associated with increased likelihood of co-morbidities. Second, most cesarean deliveries are now performed under regional anesthesia, which is known to have a lower risk of postoperative DVT compared with general anesthesia. Third, postpartum mothers are more likely to be out of bed early and frequently (because of the needs of their newborn) as compared to patients who have undergone other abdominal surgeries.
*It is interesting to note that while our study population appears to have few VTE risk factors, 78% would have warranted thromboprophylaxis after cesarean delivery per RCOG guideline. The preeclampsia rate of nearly 10% in our study is higher than that of the general obstetric population likely because preeclampsia increases the risk of cesarean delivery and our participants all had cesarean deliveries.
The researchers analysed the complications from the 700,000 pain-killing injections given each year and "found the risk of harm was at least as low as one in 23,000 - 10 times less than tends to be estimated. Experts said it was important patients were told about the true risk."
You can read the article in full here, but it continues: "Researchers said expectant mothers, in particular, should not be overly concerned as their risk of permanent harm was as low a one in 80,000."
Spinal anesthesia rather than an epidural is often used in planned cesarean deliveries today, but this research is worth being aware of for both cesarean and vaginal delivery risk information.
Gordon reports that current estimates put the figure of unnecessary cesareans at nearly 60%, while the real number may be as low as 4%. Why the huge difference?
Mainly because of inaccuracies cited on birth certificates. When government experts analyzed birth certificates and hospital discharge data, they found the actual number of [unnecessary cesarean] deliveries was closer to 4%. The study author, Emily Kahn, an epidemiologist with the U.S. Centers for Disease Control and Prevention's division of reproductive health, explains that "You can't use the birth certificate alone to determine whether or not a woman is at risk for primary caesarean delivery."
"...The CDC researchers sifted through data on 565,767 births from women who were considered at low risk for needing a C-section. The women were all 37 weeks' to 41 weeks' pregnant when they went into labor and had singleton pregnancies. All of the women delivered in Georgia hospitals between 1999 and 2004. More than 70,000 of these women ended up having a Caesarean delivery, and almost 41,000 were listed on the birth certificate as having no risk factors. Yet, in the hospital discharge data, nearly 90 percent of these women had a risk factor listed. Overall, 58.3 percent of birth certificates suggested no risk factors. But when the researchers pooled the data and combined both birth certificate data and hospital discharge data, they found the rate of Caesareans with no reported risk factors at just 3.9 percent."
Doctors don't touch birth certificates
..."Kahn said there are several possible reasons for this discrepancy. One is that the main purpose of a birth certificate is simply to record the birth. Birth certificates aren't completed by physicians, but instead rely on worksheets filled out by the mother. And, she said, hospital discharge data is used to bill the insurance companies and doctors must be very detailed on these reports to get paid, which might make them more accurate. "Doctors don't touch birth certificates," said Dr. Miriam Greene, an obstetrician at New York University Langone Medical Center and author of the book Frankly Pregnant. "The person who writes up the birth certificate might not be knowledgeable about all the risk factors for C-section, and they see the baby is fine and may think there was no issue."
My view - U.S. birth data collation is unhelpful
The story above illustrates one disadvantage with the reliance on birth certificates for analyzing cesarean delivery occurence in the U.S., but I have long talked about another area for improvement. That is, separating the number of elective/planned cesarean deliveries and the number of emergency cesarean deliveries. Many European countries already separate these types of cesarean deliveries, and this has helped to inform research into the differences in risks between the two.
Even better would be to separate 'planned cesarean deliveries in healthy women with no medial indication' (since we now know they DO exist), as this would help us to compile actual outcome data of this group without waiting for agreement to a controversial clinical trial comparing planned vaginal and cesarean deliveries in healthy women.
On a positive note, the U.S. does separate primary and repeat cesarean deliveries, which has been useful for researching health risk outcomes in multiple deliveries. It now just needs to go a few steps further in order to ensure clarity and accuracy in its cesarean data collation.
Interestlingly, the report state that according "to medical statistics, some doctors perform cesarean section at women's requests or when they need to ensure successful delivery, but some specialists disagree with the practice."
Other 2007 statistics cited
With 1.44 children per woman being born, this is a record high since 1993.
Women's average age at delivery has increased by 0.2% to 27.1 years at first delivery and 29.1 years in general.
Tuesday, January 13, 2009
What the research found
The researchers "studied a cohort of consecutive patients undergoing repeat cesarean sections performed at 19 centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network from 1999 through 2002. Women with viable singleton pregnancies delivered electively (i.e., before the onset of labor and without any recognized indications for delivery before 39 weeks of gestation) were included. The primary outcome was the composite of neonatal death and any of several adverse events, including respiratory complications, treated hypoglycemia, newborn sepsis, and admission to the neonatal intensive care unit (ICU)."
"Of 24,077 repeat cesarean deliveries at term, 13,258 were performed electively; of these, 35.8% were performed before 39 completed weeks of gestation (6.3% at 37 weeks and 29.5% at 38 weeks) and 49.1% at 39 weeks of gestation. One neonatal death occurred. As compared with births at 39 weeks, births at 37 weeks and at 38 weeks were associated with an increased risk of the primary outcome... The rates of adverse respiratory outcomes, mechanical ventilation, newborn sepsis, hypoglycemia, admission to the neonatal ICU, and hospitalization for 5 days or more were increased by a factor of 1.8 to 4.2 for births at 37 weeks and 1.3 to 2.1 for births at 38 weeks."
Obviously, some of these early deliveries are necessitated due to emerging or pre-existing medical conditions (either with the mother and/or the baby), but certainly wherever possible, doctors advise waiting until 39 weeks to deliver.
Wednesday, January 7, 2009
This simply confirms recommendations by ACOG and the NIH (among others) to wait until confirmed 39 weeks getstaional age before scheduling planned cesarean deliveries. The respiratory outcomes for babies at 39 weeks are greatly improved and therefore this study should not be used as an argument against cesarean delivery on maternal request in healthy pregnancies.
Tuesday, January 6, 2009
She also believes that the country's national cesarean rate is "absolutely too high", and says that "women's fears and a culture of negative talk around vaginal birth - both in the medical profession and broader community - should be addressed." The article continues: "The messages are that birth is dangerous; you're better to have a caesarean section," says Dr Fenwick, who is Associate Professor of Midwifery at the University of Technology Sydney.
"What we haven't done is say (to women) 'let's talk about your fear .. Let's try and help you understand that birth is a really normal, healthy life event and your body is very good at having babies'."
As many readers of my website will know, I carried out research into this area myself, and it is true that women often cite 'fear of birth' and/or 'fear of vaginal delivery pain - during and after the birth' as reasons for choosing cesarean delivery. While I agree with Dr Fenwick that it can be helpful to try and address this fear in the case of some women, it should not be forgotten or dismissed that many women do not wish to go through counselling or therapy for fear, and have made a valid and measured decision to choose the risks and benefits associated with a planned cesarean delivery instead of those associated with a planned vaginal delivery.
Don't assume that fear can or needs to be overcome
Dr Fenwick may describe birth as a "normal, healthy life event and your body is very good at having babies" but the fact is that many planned vaginal deliveries result in adverse outcomes for mother and baby, and it is perfectly reasonable for women to make the decision to avoid these risks.