WAY postdate...dangers and research?

[happyartmama]

My friend is pregnant with third child, knows exact date of last period. Using the standard EDD calculation, she would have been due June 5th....so 3 weeks "overdue" at this point. However, she was ten days past EDD with first child, 18 days past EDD with second, so knowing her history, her doctor slid her due date to the 14th. In any case, obviously that has come and gone. She's a natural childbirth teacher and comfortable (to a point) letting her body do what it needs to given that BPP, NST, fluid level check, and everything else is currently good.

Both of us have heard of placental deterioration, higher risk of maternal hemmorrhage (*she had that with #2), etc. but neither of us can find actual research about how soon the placenta decreases in viability, other risk factors, etc. Anyone know of any links or have any advice for her?

At this point, she's tried (continues to try) nipple stim., intercourse, walking, evening primrose oil, etc. Hasn't done cervadil, castor oil, or any herbs as of yet. Anyone seen a pregnancy last this long? :

[Veritaserum]

An acquaintance of mine recently went to 45 weeks and all was well. I don't have any stats for you, though, sorry!

[courtenay_e]

My mom's oldest sister carried her two babies (one was a still birth) to exactly 45 weeks.

My mom's second oldest sister also carried each of her FIVE children to 45 weeks 2 days.

I believe that the research shows that women at the highest risk for sick babies are those who were ALREADY at highest risk, for instance those with heart troubles, type 1 diabetes, and the like...but mwherbs is REALLY good at finding the research!

[bryonyvaughn]

Originally Posted by happyartmama

My friend is pregnant with third child, knows exact date of last period.

Knowing the date of conception would give an accurate due date. LMP is good if the cycle of conception would have been a 28 day cycle.

Using the standard EDD calculation, she would have been due June 5th....so 3 weeks "overdue" at this point. However, she was ten days past EDD with first child, 18 days past EDD with second, so knowing her history, her doctor slid her due date to the 14th. In any case, obviously that has come and gone. She's a natural childbirth teacher and comfortable (to a point) letting her body do what it needs to given that BPP, NST, fluid level check, and everything else is currently good.

While a "due date" is given at 40 weeks past LMP, a baby is term from 38 to 42 weeks. Based on the revised due date your friend won't be "post-dates" or post-term until the day after tomorrow.

Both of us have heard of placental deterioration, higher risk of maternal hemmorrhage (*she had that with #2), etc. but neither of us can find actual research about how soon the placenta decreases in viability, other risk factors, etc. Anyone know of any links or have any advice for her?

Post-maturity syndrome is not related to dates but placental deterioration. Premies can have post-maturity syndrome. Several years ago I talked to a DEM Tennessee midwife many years ago. She said many of her Amish first-time moms had small babies come early with significantly calcified placentas. She attributed this to their working through their pregnancy sorting tobacco leaves. She said their placentas looked like those of heavy smokers. The good news was after their first babies they work in or out of the home and had subsequent pregnancies to term with larger babies and healthier placentas.

My long in coming point is placentas decrease in viability not so much as a function of time but with continued exposure to toxins and continued deprivation of nutrients. IMO healthy women grow healthy placentas. That being said I've heard of a few women on special pregnancy diets (one example is Tom Brewer's Blue Ribbon Baby Diet) who've had very bad placentas that lasted far longer and grew far larger and healthier babies than those who examined the placentas would ever imagine.

At this point, she's tried (continues to try) nipple stim., intercourse, walking, evening primrose oil, etc. Hasn't done cervadil, castor oil, or any herbs as of yet. Anyone seen a pregnancy last this long? :

After two failed inductions my mother went 42w4d with my sister. The doctor figured she was a "slow cooker" and so didn't induce with me. After a spontaneous labor I arrived at 43w7d (should have typed 43w6d.) With my family history of post-dates pregnancies, I sought a HCP that wouldn't induce for post dates. My spontaneous post-dates pregnancies went 42w4d, 44w3d, 42w5d, 43w4d. My babies and I were healthy.

I believe a lot of the prejudice against post-dates pregnancies is fueled by babies with sever congenital abnormalities. It's my beliefs that many of these babies can't maintain the pregnancy and come very early or can't initiate labor and come very late or only upon induction. Length of normal and healthy gestations is like a bell curve; the farther you get out the fewer healthy babies are left to be born. I think the graph for gestations of babies with low likelihood of survival is the reverse. IMO many HCPs misapply that information and panic about long gestations in healthy women.

BV, at the drop of a hat is also able to rant about prejudice against big babies

[happyartmama]

Thanks for all the responses, and detailed info. bryonyvaughn; I believe it was in part because of menstrual cycle variation that her OB gave the revised due date. It's helpful to hear about other long(er) healthy pregnancies. Thanks!

[rmzbm]

With DS2 I went to 43 1/2 weeks...then was induced & had four days of labor. Then a section as the labor didn't "work." No telling how long I'd of stayed pregnant! He was fine.

[mwherbs]

in very old and more recent records the information is similar stillbirth rates make a U shaped curve 36 weeks and beyond the rate for 42 and 38 weeks is pretty close to the same--- and below is an example of the later dates and you can see that the numbers are similar even in the US (even if they aren't showing what 38 weeks would be, the others are comparable)
here is an example of the info--

1: Acta Obstet Gynecol Scand. 1997 Aug;76(7):658-62.

Comment in:
Acta Obstet Gynecol Scand. 1998 May;77(5):582-3. Acta Obstet Gynecol Scand. 1998 May;77(5):583-4.
Stillbirths and rate of neonatal deaths in 76,761 postterm pregnancies in Sweden, 1982-1991: a register study.
Ingemarsson I, Källén K. Department of Obstetrics and Gynaecology,University Hospital and Tomblad
Institute, University of Lund, Sweden.

OBJECTIVE: To study stillbirths and neonatal mortality in the postterm period.
DESIGN: Register study of information obtained from the Swedish Medical Birth Registry (MBR), National Board of Health and Welfare, Stockholm. METHODS:
Singleton pregnancies with deliveries occurring between 1982 and 1991 were
selected involving 914,702 women (of whom 76,761 had a postterm pregnancy continuing beyond the 42nd week of amenorrhea). All 2,043 records of dead infants were scrutinized before analysis of neonatal deaths. Stratification was made for year of birth, maternal age, and parity. RESULTS: Generally, the rates of stillbirths and neonatal deaths were low. The stillbirth rate was highest for primiparas at 38 completed weeks (2.72%), lowest at 40 weeks (1.23%), then increasing to 2.26% in the postterm period. The difference vs. multiparas was significant from 41 weeks onwards. Neonatal mortality was increased at 41 completed weeks for primiparas, but for multiparas it changed significantly first in the postterm period. The OR for a primipara to have an intrauterine death increased from 1.50 at 41 weeks (1.0 at 40 weeks) to 1.79 at 42 weeks and beyond. The OR for multiparas showed no sign of increase as gestation progressed.
CONCLUSIONS: The results of this study indicate an increased risk of stillbirth with gestational age for primiparas but not for multiparas. The neonatal death rate was increased for both primiparas and multiparas (after 42 completed weeks).

Publication Types:
Review

PMID: 9292640 [PubMed - indexed for MEDLINE]
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Am. J. Obstet. Gynecol. 1998 Apr;178(4):726-31.

Fetal and neonatal mortality in the postterm pregnancy: the impact of gestational age and fetal growth restriction.

Divon MY, Haglund B, Nisell H, Otterblad PO, Westgren M.
Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York, USA.

OBJECTIVE: Our purpose was to examine the impact of gestational age and fetal growth restriction on fetal and neonatal mortality rates in the postterm
pregnancy. STUDY DESIGN: All deliveries occurring in Sweden between Jan. 1, 1987, and Dec. 31, 1992, were evaluated for participation in this study. Data were derived from the National Swedish Medical Birth Registry. Pregnancies were selected for inclusion in the study on the basis of the following criteria: (1) singleton pregnancy, (2) reliable dates, (3) gestational age > or = 40 weeks, and (4) maternal age 15 to 44 years. Fetal growth restriction was defined as birth weight <2 SD below the mean for gestational age. A total of 181,524 pregnancies met the inclusion criteria and formed the study population. Fetal and neonatal mortalities at 40 weeks' gestation were used as reference levels. Logistic regression analysis was used to estimate the independent effects of gestational age and fetal growth restriction on fetal and neonatal mortality rates. RESULTS: A significant rise in the odds ratio for fetal death was detected from 41 weeks' gestation and on (odds ratios 1.5, 1.8, and 2.9 at 41, 42, and 43 weeks, respectively). Odds ratios for neonatal mortality did not demonstrate a significant gestational age dependency. Fetal growth restriction was associated with significantly higher odds ratios for both fetal and neonatal mortality rates at every gestational age examined (with odds ratios ranging from 7.1 to 10.0 for fetal death and from 3.4 to 9.4 for neonatal death). CONCLUSIONS: Postterm pregnancies have long been considered to be at high risk for adverse perinatal outcome. This study documents a small but significant increase in fetal mortality in accurately dated pregnancies that extend beyond 41 weeks of gestation. This
study also demonstrates that fetal growth restriction is independently associated with increased perinatal mortality in these pregnancies.

Publication Types:
Research Support, Non-U.S. Gov't

PMID: 9579434 [PubMed - indexed for MEDLINE]