Need to induce at 42 weeks? Maybe it just runs in the family.

An interesting study was released online in BJOG, An International Journal of Obstetrics and Gynecology. Apparently, parents born after 42 weeks are more likely to have babies born just as late.

The study examined the relationship between post-dates births (pregnancies extending beyond 41, 42, and 43 weeks) and parents who were themselves born post-term. This study shows that parents who were themselves born post-term are more likely to have babies born post-term. The genetic link seems to be more prevalent with mothers (49% increase) than fathers (23% increase).

So, what does this mean for the average expectant parent?

Know your family history! If mom is still pregnant at 42 weeks, but she was born at 42 weeks 5 days, there is a good chance that baby is just not done cooking yet. As long as baby checks out as healthy on a bio-physical profile, and mom is taking good care of herself with no medical problems (lucky for most of us, discomforts like a sore back don’t count as medical problems), there is probably no need to rush into an induction. The same thing is true if dad was the one born later than average.

So, what can you do?

If you are expecting (mom and dad), find out your family history. Ask your mom or whoever else might know when you were born in relation to your due date. Also ask about your siblings, and if your mom and dad know if *they* were also late. Discuss this information with your doctor or midwife sometime in your third trimester, preferably before 40 weeks, if not earlier. Try to come to an agreement about when induction would be recommended. Some birth attendants may be willing to wait longer with a good biophysical profile and a family history of long pregnancies.

Some birth attendants really are ok with long pregnancy under these circumstances. I used to know a local childbirth educator who had long pregnancies run in her family. She had at least 4 kids when I last knew her (she moved out of state some years ago), and if I remember right, not one was born before 42 weeks. Of course, neither was she. It just ran in the family. Fortunately, she also had excellent lifestyle habits, so pregnancy – even a long one – was comfortable for her, relatively speaking.

What ELSE can you do if you don’t want to go post-dates?

Your body may not give you a choice. But there are a lot of other factors that influence how long pregnancy lasts. Some factors you can address include:

  • Make sure your pelvis and baby are in a good position by practicing good posture habits for pregnancy and seeing a Webster-certified chiropractor (see ).
  • Make sure your body is well nourished, especially essential fatty acids.
  • Reduce your exposure to endocrine-disrupting chemicals.
  • Try not to stress if your body is not showing signs of labor when you think it should.

If you would like to discuss the specific needs your body may have to be ready for labor, feel free to reach out.

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Morken N-H, Melve K, Skjaerven R. Recurrence of prolonged and post-term gestational age across generations: maternal and paternal contribution. BJOG 2011; DOI: 10.1111/j.1471-0528.2011.03154.x.


Posted by Melinda in Birth, Long Pregnancy, Pregnancy

Tags: biophysical profile, genetics, induction, post-dates, post-term, postterm, pregnancy, pregnancy length, pregnant, should I induce

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