Postdate VBAC Ammunition

I've had a few people ask me how I dealt with the pressure to schedule a c-section as I approached my due date. I had a successful VBA2C at 40w 5d (You can read my birth story here if you're interested). The pressure from my doctors to schedule a c-section for the date of my due date was tremendous, so I did a lot of research so that I could be prepared to stand my ground. I want to be clear that I am in no way an expert. So use this post as a starting point rather than as the thing you rely on. I'm just a mom who had to deal with all this. Here is what I came up with:

First, going past your due date does NOT make you postdate. A pregnancy is not considered postdate until 42 weeks gestation. That's important to know in and of itself.

Second, the research speaks for itself. There is no medical reason for your doctor to schedule a c-section just because you're approaching or have gone past your due date. Here is some of the research that I found in peer reviewed journals. It will be important to be familiar with these studies when dealing with your provider. Not only because you need to be educated in this matter in order to make an informed decision. But doctors have been known to outright lie to their patients. You'll need to be prepared for that.


Peer Reviewed Journals

•    Obstet Gynecol. 2005 Oct;106(4):700-6. (http://www.ncbi.nlm.nih.gov/pubmed/16199624 )
  Safety and efficacy of vaginal birth after cesarean attempts at or beyond 40 weeks of gestation 
  •  RESULTS: When the cohort was defined as 41 weeks or more of gestation, the risk of a failed VBAC was again significantly increased (35.4% compared with 24.3%, odds ratio 1.35, 95% confidence interval 1.20-1.53), but the risk of uterine rupture or overall morbidity was not increased. CONCLUSION: Women beyond 40 weeks of gestation can safely attempt VBAC, although the risk of VBAC failure is increased
•  J Reprod Med. 1999 Jul;44(7):606-10. (http://www.ncbi.nlm.nih.gov/pubmed/10442323 )
  Safety and efficacy of attempted vaginal birth after cesarean beyond the estimated date of delivery.
  •  CONCLUSION: The patient and her family can be reassured that passing her due date does not alter the efficacy or safety of a trial of labor. No change in counseling is warranted simply due to the completion of 40 weeks' gestation.
•  Obestet Gynecol. 2001; 97: 391-3.
  Trial of Labor After 40 Weeks' Gestation in Women With Prior Cesearean
  • Conclusion: The risk of uterine rupture does not increase substantially after 40 weeks but is increased with induction of labor regardless of gestational age. Because spontaneous labor after 40 weeks is associated with a cesarean rate similar to that following induced labor before 40 weeks, awaiting spontaneous labor after 40 weeks does not decrease the likelihood of successful vaginal delivery.
• http://www.ncbi.nlm.nih.gov/pubmed/12679819
  • Results: “...Fetal macrosomia does not appear to be a contraindication to VBAC, as success rates exceeding 50% are achieved and uterine rupture rates are not increased. .... Post-dates pregnancies may deliver successfully by VBAC in greater than two-thirds of cases.
• http://www.sogc.org/guidelines/public/155E-CPG-February2005.pdf
  • Postdatism
    Three studies have examined postdatism and TOL after Caesarean.106–108 In 2 of these studies, the rate of successful VBAC and uterine rupture in women who delivered at less than 40 weeks’ gestation was compared with those who delivered at more than 40 weeks.106,107 Success rates for VBAC after 40 weeks were reported from 65.6%107 to 73.1%106 and were comparable to success rates for women who delivered before 40 weeks’ gestation.106,107 Zelop et al. also compared the risk of uterine rupture in women who delivered before and after 40 weeks’ gestation in spontaneous labour and induced labour.108 They reported that the risk of uterine rupture in a TOL after Caesarean after 40 weeks’ gestation was not significantly increased when compared with women who delivered before 40 weeks, whether in spontaneous labour (1.0 % vs. 0.5%, P = 0.2, adjusted OR, 2.1; 95% CI, 0.7–5.7) or after induction (2.6% vs. 2.1%, P = 0.7, adjusted OR, 1.1; 95% CI, 0.4–3.4).108
  • Recommendation
    • 18. Postdatism is not a contraindication to a TOL after Caesarean (II-2B).

The key thing that I took away from these articles is that if there is that when you go postdate, the increase in the risk of uterine rupture is negligible. Some studies show that it doesn't go up at all! If you're interested in what non postdate rates are, check out this article:

Labor Outcomes With Increasing Number of Prior Vaginal Births After Cesarean Delivery

Some doctors like to use scare tactics and may use phrases like "you don't know what I've seen" or "its been known to happen". Of course this doctor has seen some horrible things and of course its been known to happen. But chances are, it's not going to happen to you. So let's stick with the statistics. Ask your doctor to please show you the specific studies they are using as validation for placing a time limit on your pregnancy. What they're going to come up with is studies showing the risks for postdate pregnancy such as oligohydramnios, meconium aspiration, placental insufficiency and macrosomia which may result in cephalopelvic disproportion. Lots of big scary words there, right? But guess what? Those are the exact same risks every woman, VBAC or first time mom, faces when going postdate. And when was postdate again? Oh yeah, 42 weeks. NOT 40 weeks and 1 day.

Now we don't want to endanger our sweet little babies because we're so determined to have that birth experience that we dream of. But there are things we can do to ensure we're doing everything possible to protect our baby AND get our VBAC! Here's what you need to do.

First, daily kick counts are very important. Make sure sure that baby keeps moving! And don't second guess yourself. If you feel like something is wrong, call L & D! They will either reassure you or tell you to come in.

Second, (and this may reassure your provider as well) agree to surveillance after 41 weeks. This may involve the following tests:

• Nonstress Test (NST)
• Contraction stress test (CST)
• Biophysical Profile (BPP)
• Amniotic Fluid Volume Assessment (AFV)

Know that if testing shows any problems at all, the doctors are obligated to deliver the baby. So be prepared for that. But again, you don't want to endanger your baby. However, if all testing is normal, there is no reason that you can't wait until a date that you're comfortable with. I was ready to wait it out until 43 weeks!

If your provider continues to pressure you, ask the following questions:

• Has testing revealed a problem with the baby?
• Has testing revealed a problem with the placenta?
• Has testing revealed a problem with me?

If the answer is no to all of the above, then why do they want to do a c-section? If it's just because they're uncomfortable with a post-date VBAC, that's simply not a good enough reason to start cutting.

In the end, you need to do everything you can to educate yourself so that you can make the best decision for you and your baby. It's not your doctor's decision, it's yours. It's not about what they will or will not "let" you do. They don't get to make decisions for you regarding your care. That's your job, and that's exactly what you need to tell them. 

The following isn't my phrase. I found it here: (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1948092/) But I love it. 

"In using specific phrases (e.g., “I hear…I understand…I decline…”), an educated, respectful patient demonstrates she or he has a clear understanding of the procedure and chooses an informed-refusal or informed-consent course of action for the treatment."