Long-Term Implications of a High Cesarean Rate in Obese Women

April is Cesarean Awareness Month.

This is an annual observance sponsored by the International Cesarean Awareness Network (ICAN) to raise awareness of the implications of a high cesarean rate and lack of access to VBAC (Vaginal Birth After Cesarean).

It's always important to remind readers that this observance is not meant to make anyone feel bad about having had a cesarean, or to imply that having a cesarean makes you "less of a mother" or "less of a woman." Nonsense.

Cesareans can be life-saving and wonderful when used appropriately, but they are not risk-free. When over-utilized, they can have dramatic negative consequences too, especially long-term.

Cesarean Awareness Month is not about any one person's experience at all, but rather about the widespread public health implications of a high cesarean rate and lack of access to VBAC. And this certainly is an under-appreciated public health care issue.

Long-Term Risks of Too Many Cesareans

As we posted about extensively last year, one of the overlooked long-term consequences of a high cesarean rate is an increase in the risk for placental disorders.

Specifically, there is a substantial increase in the risk for:

• placenta previa (a low-lying placenta which is near or which covers the cervix)
• placental abruption (where the placenta pulls away from the uterus prematurely)
• placenta accreta (an abnormally-attached placenta that does not detach after birth). 

Here is yet another study that confirms cesarean section as a strong risk factor for placental disorders.

Although this meta-analysis does not evaluate the risk by number of prior cesareans, merely by the presence of prior cesarean, a number of other studies have shown that the risk increases strongly with multiple prior cesareans in a dose-dependent manner.

This is why it is important not to have cesarean after cesarean unless it is medically necessary, and why the ban on VBACs in many hospitals is so frustrating.

The ban on VBAC (Vaginal Birth After Cesarean) in some places means that thousands of women have been and are continuing to be subjected to unnecessary cesareans. This in turn is raising the incidence of placental disorders like previa, abruption, and accreta, as well as maternal morbidity from the surgeries and the very serious complication of cesarean scar pregnancy.

Although with good care, many of these complications can be handled, they do often result in life-threatening hemorrhages, bladder or renal damage, uterine ruptures, hysterectomies, prematurity, stillbirth, and even maternal deaths at times.

Although these complications are overall rare, they are happening to real women, with real results, sometimes devastating ones.

This is why it is SO important to do cesareans only when truly indicated, to avoid automatic repeat cesareans, and to keep VBACs available as an option everywhere.

Implications for Women of Size

Long-term complications of cesareans is a particularly pertinent issue for women of size.

If a 32.8% overall national c-section rate is too high, then the rate in "obese" women is an even GREATER reason for concern because in most studies it starts at 30% and goes as high as 40%, 50%, 60%, and even 70% in some places and groups.

And many of the cesareans done in obese women are done without any labor at all. Many care providers have a de-facto policy of automatic "elective" cesareans for very obese women, despite the fact that this does not improve outcomes.

This disproportionately exposes the larger mother to the risks of cesareans (hemorrhage, infection, blood clots, bladder injury, and anesthesia problems) and subsequent placental disorders. This is insane. Yet few in the obstetric community even question the high cesarean rate in obese women.

This is why observing Cesarean Awareness Month is so important. It's not about putting down anyone who had a c-section, but to raise awareness of the health implications of a too-high cesarean rate.

In addition, it's time for care providers to focus on the implications of the sky-high cesarean rate in women of size and what can be done to lower that rate.

This is why I always observe Cesarean Awareness Month here and why I urge others to do so too.


References

Cesareans and Subsequent Placental Disorders

J Perinat Med. 2014 Feb 24. pii: /j/jpme-ahead-of-print/jpm-2013-0199/jpm-2013-0199.xml. doi: 10.1515/jpm-2013-0199. [Epub ahead of print] Cesarean section and placental disorders in subsequent pregnancies - a meta-analysis. Klar M, Michels KB. PMID: 24566357

...OBJECTIVE: To examine the association between CS and three major types of placental disorders (placental abruption, placenta previa, and placenta accreta with its variants increta/percreta) in subsequent pregnancies. SEARCH STRATEGY: ...observational studies published between January 1990 and July 2011 for examining the association between CS and placental disorders in subsequent pregnancies, without focusing on the effect of increasing number of CSs... DATA COLLECTION AND ANALYSIS: Five cohort and 11 case-control studies met the inclusion criteria for this meta-analysis...MAIN RESULTS: The calculated summary odds ratio was 1.47 (95% confidence interval, CI: 1.44-1.51) for placenta previa, 1.96 (95% CI: 1.41-2.74) for placenta accreta, and 1.38 (95% CI: 1.35-1.41) for placental abruption. CONCLUSION: In this meta-analysis, cesarean delivery appeared as a consistently reported risk factor for all three major forms of placental disorders in subsequent pregnancies.

Obstet Gynecol Clin North Am. 2013 Mar;40(1):137-54. doi: 10.1016/j.ogc.2012.12.002. Placenta accreta, increta, and percreta. Wortman AC, Alexander JM. PMID: 23466142

Placenta accreta is an abnormal adherence of the placenta to the uterine wall that can lead to significant maternal morbidity and mortality. The incidence of placenta accreta has increased 13-fold since the early 1900s and directly correlates with the increasing cesarean delivery rate...

Placenta. 2012 Apr;33(4):244-51. doi: 10.1016/j.placenta.2011.11.010. Epub 2012 Jan 28. Placenta accreta: pathogenesis of a 20th century iatrogenic uterine disease. Jauniaux E, Jurkovic D. PMID: 22284667

...Overall these data support the concept that abnormal decidualization and trophoblastic changes of the placental bed in placenta accreta are secondary to the uterine scar and thus entirely iatrogenic.

Am J Obstet Gynecol. 2011 Dec;205(6 Suppl):S2-10. doi: 10.1016/j.ajog.2011.09.028. Epub 2011 Oct 6. Long-term maternal morbidity associated with repeat cesarean delivery. Clark EA, Silver RM. PMID: 22114995

Concern regarding the association between cesarean delivery and long-term maternal morbidity is growing as the rate of cesarean delivery continues to increase. Observational evidence suggests that the risk of morbidity increases with increasing number of cesarean deliveries. The dominant maternal risk in subsequent pregnancies is placenta accreta spectrum disorder and its associated complications. A history of multiple cesarean deliveries is the major risk factor for this condition. Pregnancies following cesarean delivery also have increased risk for other types of abnormal placentation, reduced fetal growth, preterm birth, and possibly stillbirth. Chronic maternal morbidities associated with cesarean delivery include pelvic pain and adhesions. Adverse reproductive effects may include decreased fertility and increased risk of spontaneous abortion and ectopic pregnancy. Clinicians and patients need to be aware of the long-term risks associated with cesarean delivery so that they can be considered when determining the method of delivery for first and subsequent births.

J Matern Fetal Neonatal Med. 2011 Nov;24(11):1341-6. doi: 10.3109/14767058.2011.553695. Epub 2011 Mar 7. The effect of cesarean delivery rates on the future incidence of placenta previa, placenta accreta, and maternal mortality. Solheim KN1, Esakoff TF, Little SE, Cheng YW, Sparks TN, Caughey AB. PMID: 21381881

OBJECTIVE: The overall annual incidence rate of caesarean delivery in the United States has been steadily rising since 1996, reaching 32.9% in 2009. Primary cesareans often lead to repeat cesareans, which may lead to placenta previa and placenta accreta. This study's goal was to forecast the effect of rising primary and secondary cesarean rates on annual incidence of placenta previa, placenta accreta, and maternal mortality. METHODS: A decision-analytic model was built using TreeAge Pro software to estimate the future annual incidence of placenta previa, placenta accreta, and maternal mortality using data on national birthing order trends and cesarean and vaginal birth after cesarean rates. Baseline assumptions were derived from the literature, including the likelihood of previa and accreta among women with multiple previous cesarean deliveries. RESULTS: If primary and secondary cesarean rates continue to rise as they have in recent years, by 2020 the cesarean delivery rate will be 56.2%, and there will be an additional 6236 placenta previas, 4504 placenta accretas, and 130 maternal deaths annually. The rise in these complications will lag behind the rise in cesareans by approximately 6 years. CONCLUSIONS: If cesarean rates continue to increase, the annual incidence of placenta previa, placenta accreta, and maternal death will also rise substantially.

Obesity and Over-Utilization of Cesareans

Am J Obstet Gynecol. 2012 May;206(5):417.e1-6. doi: 10.1016/j.ajog.2012.02.037. Epub 2012 Mar 7. Maternal superobesity and perinatal outcomes. Marshall NE1, Guild C, Cheng YW, Caughey AB, Halloran DR. PMID: 22542116

OBJECTIVE: The purpose of this study was to determine the effect of maternal superobesity (body mass index [BMI], ≥ 50 kg/m(2)) compared with morbid obesity (BMI, 40-49.9 kg/m(2)) or obesity (BMI, 30-39.9 kg/m(2)) on perinatal outcomes. STUDY DESIGN: We conducted a retrospective cohort study of birth records that were linked to hospital discharge data for all liveborn singleton term infants who were born to obese Missouri residents from 2000-2006. We excluded major congenital anomalies and women with diabetes mellitus or chronic hypertension. RESULTS: There were 64,272 births that met the study criteria, which included 1185 superobese mothers (1.8%)...Almost one-half of all superobese women (49.1%) delivered by cesarean section, and 33.8% of superobese nulliparous women underwent scheduled primary cesarean delivery. 

BJOG. 2011 Mar;118(4):480-7. doi: 10.1111/j.1471-0528.2010.02832.x. Epub 2011 Jan 18.
Planned vaginal delivery or planned caesarean delivery in women with extreme obesity.
Homer CS1, Kurinczuk JJ, Spark P, Brocklehurst P, Knight M. PMID: 21244616

OBJECTIVE: To compare the outcomes of planned vaginal versus planned caesarean delivery in a cohort of extremely obese women (body mass index ≥ 50 kg/m(2)). DESIGN: A national cohort study using the UK Obstetric Surveillance System (UKOSS). SETTING: All hospitals with consultant-led maternity units in the UK. POPULATION: Five hundred and ninety-one extremely obese women delivering in the UK between September 2007 and August 2008...CONCLUSIONS: This study does not provide evidence to support a routine policy of caesarean delivery for extremely obese women on the basis of concern about higher rates of delivery complications, but does support a policy of individualised decision-making on the mode of delivery based on a thorough assessment of potential risk factors for poor delivery outcomes.