A mother's intuition...

Is not always right.  I’d been feeling crappy for a couple of weeks—tired, a little queasy.  Then one day at 7w2d pregnant, all of that went away.  Knowing that sudden loss of symptoms can be a bad sign, I started freaking out.  (Although I’d had a bad feeling about the pregnancy from the beginning.)  At 7w3d I called and asked for an appointment.  By 4pm that afternoon, I started bleeding again—over a week after my last episode.  But this bleeding was different than the last two episodes.  It was heavier than spotting, but certainly not filling a pad (like the first time).  And it was more mucus-ey (TMI?).  So I was certain my pregnancy was done for.  I went home and cried my little eyes out.

At my appointment at 7w4d, I had completely convinced myself (and my husband and my doctor?) that this was the end.  Imagine my surprise when we saw a little embryo still growing, measuring on time with a little heartbeat.  (Although that damn yolk sac is still absolutely puny – still 2.5mm.  It should be 4mm by now.  My doc did not seem too worried—repeating what we heard last week that they worry more about big yolks than small ones.)

With respect to the bleed, they could not see anything.  So I don’t have a hematoma (pooling of blood).  When I do bleed (the cause being a mystery), it just falls out of me, hopefully leaving that little fetus totally undisturbed.  Nevertheless, they want me to rest, which means no exercise, heavy lifting, stairs, sex, etc.  In other words, Netflix and chill.

SO here we are.  This is certainly not a sure thing, but my doc says with a chromosomally normal embryo and a “normal” 7 week appointment, the miscarriage rate is like 5%.  My chances of failure are probably a bit higher because of my history and prior hematoma and teeny yolk sac, but they’re not terrible.

I’m just going to wait.  And try—really TRY—not to freak out over every little thing.*

*Still no morning sickness, but my boobs are now super sore.  Not that I’m worried about that one way or the other….

"Injecting" some levity

I feel like my posts have been really sad recently, so I want to post a few funny anecdotes.

First, I’m still doing the intermuscular progesterone shots.  Yes, the needles as big as toothpicks.  I think my husband hates giving me the shots more than I hate getting them.  Anyway, the other day my husband had just given me my shot and he was getting ready to put a Band-Aid on the spot.  The un-sheathed needle was sitting on our coffee table.  As he reached for the Band-Aid, he bumped the needle and it fell off of the table—and right into his leg!  I heard “aaaaaaah!” and then turned around to see the needle stuck through his pants and deep into his thigh.  I know it really hurt, but the look on his face (“oh, SHIT! That dirty needle sticking out of me really f-ing hurts!”) was priceless.  I could not stop laughing for like five minutes.  He  was pretty good natured about it.

Second, when we went to our heart beat appointment last week, we bumped into one of my husband’s good friends on his way out.  We had no idea he was seeing a fertility doctor, but he just got married and he and his wife are older, so no surprise.  Anyway, he was alone.  There’s only one thing a man is doing at a fertility doc’s office alone—leaving a sample (blood or… the other kind).  And he was coming from the part of the office where you only leave one kind of sample.  He was obviously pretty embarrassed.  We assured him—truthfully—that we bump into people there all the time.  My husband texted him after that he was sorry we interrupted his walk of shame.  ;)

Malaise

I’m pretty depressed right now.  I feel like shit—but not morning sickness.  Just like general yuckiness.  I can’t work out.  I can’t drink.  No sex.  I’m tired.  I have this overwhelming feeling of doom.  I hate the drugs and the uncertainty and the worry.  BLAH.

Okay, stay with me here, I’m going to lay out my feelings / grievances in a bit of a winding fashion….

After my anencephaly pregnancy, I was close to 150 lbs.  As my long-time readers may recall, I was ABSOLUTELY famished for the first 17 weeks of that pregnancy and gained around 15lbs—much more weight than I gained during that time period of my pregnancy with my son.  (I’ve wondered since then if my hunger / nausea was particularly strong because of the anencephaly.  I’ve never read anything suggesting as much, but I still wonder.)  And when I got pregnant that time, I was still carrying a little weight (about 5 lbs) from after my pregnancy with my son.  AND when I got pregnant with my son, I was about 5lbs heavier than my ideal weight (because I’d cut back on exercise—eggs hate sweat, or so I’ve been told).

Anyway, I raise all of this because after my anencephaly pregnancy I was 25lbs heavier than my ideal weight.  I certainly was not morbidly obese, but I was definitely at a weight that I did not need to stay at.  Unfortunately, the weight was almost IMPOSSIBLE to lose.  But, because I’m never going to use my eggs again, I was not particularly worried about sweat.  And after working out just about every day very hard for 8 months (I would always take 2 weeks off during my failed frozen embryo transfers) I lost ALL of the weight.  I was downright skinny—back to my college weight!!  Awesome, right?  

Yes, but I think that’s contributing to my current misery.  I got so used to the endorphins from a good workout that just sitting around is making me FREAKING MISERABLE.  M-I-S-E-R-A-B-L-E.  And sitting around being miserable, I just see the weight coming on again.  I know I shouldn’t worry about this, but I hate thinking I’m going to gain a ton of weight only to have this not work out.

My husband is encouraging me to ease back in to working out, for my mental health.  He points out that this week they could not find any evidence of the hematoma and that the doctor (not my regular) said I could do light exercise if I wanted to.  But I’m nervous.  I was bleeding just last weekend.  I don’t feel ready to work out yet.  If, at my follow-up appointment next week (at 8 weeks) there’s no heart beat or a super tiny yolk sac or the hematoma is back, I’ll never forgive myself if I start up with exercise (or sex) too early.  I know that seems sort of silly, but I’ve been through a lot.  I’m allowed to be a little crazy.

Speaking of crazy, I told my husband today I don’t even want a second kid.  That seems impossible to believe, considering all the shit I’ve chosen to put myself through over the past 2+ years, but I really meant it.  I mean, yes, if it had been easy I would have LOVED to have a second kid.  (My heart breaks a little bit whenever I walk into the nursery we set up for the anencephaly pregnancy.)  But I just really hate that the last two years of my life have been dominated with so much stress and sadness and uncertainty.  If I could go back in time, I would have had my son and then donated all of my pregnancy clothes to Goodwill and never looked back.

But, as my husband tells me all the time, hindsight is 20/20.  And at this point we have this pregnancy, which could theoretically be successful (although the feeling of malaise is strong), and I have one last transfer in me.  (As I told my husband, no embryo left behind.)

So I’m just going to try to suck it up as much as I can.  And maybe go for a short swim tomorrow.

Expecting Science

Over the years, I’ve run across a lot of blogs on fertility and related issues, and one I just found is my new favorite:

http://expectingscience.com/

The author is a research scientist and she takes topics and breaks down the research surrounding them.  Very interesting.  Her most recent one is on morning sickness and miscarriage risk:

http://expectingscience.com/2016/03/11/nausea-and-the-risk-of-miscarriage-how-much-does-morning-sickness-lower-your-risk/

I won’t summarize the whole thing (it’s worth a read), but as it relates to me she says that for moms over 35 that experience morning sickness, the risk of miscarriage is 1/5 of women who do not experience it.  Woah!  She does point out that 20-30% of women who go on to have healthy pregnancies do not experience any morning sickness (I didn’t have any with my son).  She also notes that the more kids you’ve had the more likely you are to have morning sickness, that your ethnicity may play a part, and (in the notes) that older women tend to have less severe morning sickness.

She also notes that before 7 weeks, a lack of nausea does not predict miscarriage risk.  But if you do not have morning sickness by 8 weeks, that is predictive of a higher risk of miscarriage.

Whooh!  I’m 6 weeks 5 days and I have nothing.  (Maybe a teeny bit—a general sense of malaise.  I think that might be stress-related, though.)

As I said, I had no morning sickness with my son.  I did have mild morning sickness with my anencephaly pregnancy.  (No vomiting, but very, very nauseated and completely starving at the same time.  Yech.)  I suffered happily, knowing it was a good sign as it related to miscarriage risk.

Like most things relating to pregnancy, I have no control over whether I have morning sickness or not.  I just have to sit and wait to see what happens.

Diagnosing anencephaly

Going back to the theme of never relaxing or celebrating good news….  The minute I left my heart beat appointment, I immediately (like, in the parking lot) called my OB’s office and demanded a referral to a high-risk OB so that I could get a transvaginal ultrasound appointment at 9 weeks to see if anencephaly could be diagnosed or ruled out.

Anencephaly is one of the most certain prenatal diagnoses.  And I’ve read it can be seen on an ultrasound as early as 8 weeks, when the crown to rump length is 32mm or greater:

http://onlinelibrary.wiley.com/doi/10.1002/uog.14075/epdf

(The researchers call it the “Mickey Mouse” sign.)

See this article indicating what the tech should be looking for:

http://www.stritch.luc.edu/lumen/MedEd/Radio/curriculum/OBGYN/Anencephaly.htm

Here’s an article discussing diagnosis with 100% certainty by 12 weeks when a transvaginal ultrasound is used:

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&sqi=2&ved=0ahUKEwi4heyXlKbLAhXlmnIKHVbrABcQFggiMAE&url=http%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1046%2Fj.1469-0705.1999.13030196.x%2Fpdf&usg=AFQjCNFqugdUdp8eXVwswJXusvY6ASqSLw&bvm=bv.115339255,d.bGQ

(The researchers also call it the “Mickey Mouse” sign.)

Obviously I’m going to be on pins and needles through this whole pregnancy.  And one of the things I will be looking for is certainty, as soon as possible, that this is not a repeat of our last pregnancy.  I’m glad that I know what to look for.  Screw you, Mickey.

Yolk sacs – size really does matter

Ugghhhhh.  I really wish I could just hear the ultrasound tech say, “there’s the heartbeat!” and be super excited and go home and start decorating the nursery and picking baby names.

But that’s not who I am.  I’ve been through too much.  I’ve seen too much.

Today I was 6w3d.  And I got what should be, by all accounts, great news.  There’s a heartbeat.  My doc’s office does not give a heart rate measurement, but I pressed repeatedly (“is it slow?  It looks slow”) to be told it looks fine and not slow.  (He said it would be obvious the heart rate was slow if it was below 100bpm.  I’m not so sure about that.)  The subchorionic hematoma is invisible.  (Cured!)  The crown to rump length is 5.6mm—right where it should be.  (Recall yesterday I said the average was 5.4mm with a range of 3.4mm (5^th percent) to 7.9mm (95^th percent).)  The gestational sac diameter was 20.9mm, right where it should be.  (Ave 17.4mm, range 11.7mm (5%)-24.3mm (95%).)  And the yolk sac diameter was 2.5mm, far far far below what it should be.  (Ave 3.6mm, range 2.7mm (5%) to 4.5mm (95%).)

Wait, what?  

You heard me—now I’m worried about my tiny yolk sac.

It literally never occurred to me to worry about the size of my yolk sac until I looked at the “average” and “normal” (ie. 5^th-95^th percentile) numbers.  My yolk sac is TEENY.  Well below the 5^th percentile.

Cut to me reading whatever I can about small yolk sacs.  People tend to agree that below 3mm at this gestational age is an abnormally small yolk sac, but the only articles I could find suggesting increased adverse outcomes were for yolk sacs smaller than 2mm.  Interestingly, large yolk sacs (above 6mm) were associated with adverse outcomes.

What the heck?!  Well, apparently a large yolk sac can indicate that the embryo is developing abnormally (and not using its yolk?).  And a small yolk sac suggests there are not enough nutrients to sustain the developing pregnancy.  (I couldn’t find any medical journal articles suggesting that, just a website.)

Okay, this article says in the first trimester a normal yolk sac is 3-6mm and that a yolk sac of less than 3mm is “too small” and “related to spontaneous abortion prediction”:

http://www.jaypeejournals.com/eJournals/ShowText.aspx?ID=98&Type=FREE&TYP=TOP&IN=_eJournals/Journal%20of%20Ultrasound%20in%20Obstetrics%20and%20Gynecology.jpg&IID=11&AID=2&Year=2008&isPDF=YES

BUT, later in the article it suggests that at 6 weeks pregnant, the mean is 3.1mm in a “normal” pregnancy with a range of 2.5-3.8mm.  Okay, assholes, so if 3.1mm is the mean in a normal pregnancy, how can below 3mm be the beginning of the bad range?  Later the authors cite an article (by Green) that suggests that between 8 and 12 weeks pregnant, a yolk sac diameter below 2mm is associated with an adverse pregnancy outcome.

So basically I’m calling bullshit on the suggestion that 3mm is “too small.”  The only data the authors cite suggests that 2mm is “too small.”  (I could not find a free full copy of the Green article.)

This article suggests that for women of 6-9 weeks pregnant, a yolk sac of 2-5mm is normal:

http://saspublisher.com/wp-content/uploads/2015/03/SJAMS-32A543-550.pdf

“The pregnancy outcome was optimum when the sac diameter ranged between 2 to 5 mm. The live pregnancy rate increased to 99.2% (250/252) with this yolk sac diameter range. However when the yolk sac diameter fell outside of this range live pregnancy rates were significantly decreased (for < 2 mm - 50%, > 5 mm – 66.6%).”

In other words, half of the women with “small” yolks (under 2mm) miscarried.  33% of the women with large yolks (above 5mm) miscarried.

The article also explains why a large yolk sac is a problem: “If a large yolk sac persists, it indicates aberrant embryonic development and high chance of miscarriage.”  There was no explanation for the cause of a small yolk sac or the reason for adverse outcomes with a small yolk sac.

The article also summarizes a bunch of other studies on embryo heart rate and yolk sac diameter.

The article also suggests that a study by Figueras “found that yolk sac volume outside the 5th to 95th percentile were associated with significant occurrence of retrochorialhaematoma and subsequent pregnancy loss.”  (That study’s range was 2-5mm as well.)  

Okay, wait, back to the hematoma?!?!  Retroplacental hematomas are hematomas entirely behind the placenta and not touching the gestational sac.  (As opposed to subchorionic hematomas, which are between the chorion and endometrium.)

Okay, here’s the Figueras article that talks about yolk sacs and hematomas:

https://www.researchgate.net/publication/10759938_Three-dimensional_yolk_and_gestational_sac_volumeA_prospective_study_of_prognostic_value

For women from 6-10 weeks pregnant, they collected a number of things, including fetal heart rate (FHR), mean gestational sac diameter (GSD), mean yolk sac diameter (YSD), gestational sac volume

(GSV), yolk sac volume (YSV) and presence of a subchorionic hematoma affecting at least 30% of the chorionic plate.  The authors found that maternal age (above 34), yolk sac volume, mean gestational sac diameter below than the 5th percentile, gestational sac volume below than the 5th percentile, and fetal heart rate below than the 5th percentile or above the 95^thpercentile, were all significantly associated with increased miscarriage.  Mean yolk sac diameter and presence of hematoma “showed no significant association with abortion.”  

Music to my ears!

Well, let’s not get too excited.  They suggest, “There was a tendency toward an association, although not statistically significant, between YSD [yolk sac diameter] and abortion [miscarriage].”  It mentioned nothing about hematomas beyond what I mentioned above.  Sigh.

Here’s another article that considers 2-5mm to be a “normal” yolk sac diameter for 5-6.5 weeks pregnant.  (Although it also notes elsewhere that 3-6mm is “normal”.)

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4258241/

Again, it suggests that for abnormally large yolk sacs, “Larger yolk sac diameters may represent evidence of certain diseases and the pregnancy loss in these pregnancies is reflective of the presence of such underlying diseases.”

But, again, there is no suggestion of why a small sac was a problem.  It just suggests, “The lack of a yolk sac or a smaller than gestational age yolk sac diameter are indicative of pregnancies that may result in spontaneous abortion. Pregnancies with a very large yolk sac are generally always associated with poor outcomes”

The source for the small sac diameter reference in that article is here:

http://opensample.info/yolk-sac-size-and-embryonic-heart-rate-as-prognostic-factors-of-first-trimester-pregnancy-outcome

This article sets up four groups:

Group I (42nd to 55th day (6–7weeks + 6 days)): pregnancy continued

Group II (56th to 69th day (8–9 weeks + 6 days)): pregnancy continued

Group III (70th to 84th day (10–12 weeks)): pregnancy continued

Group IV (all): pregnancy did not continue

In other words, three of the groups had continued pregnancies and one was the miscarriage group.  Then they measure embryo heart rate and yolk sac diameter in the two groups:

Embryonic heart rate and yolk sac diameter in the first trimester
	Embryo Heart Rate (bpm)			Yolk Size Diameter (mm)
	Group mean (ave)	Min-Max	Median (middle)	Group mean (ave)	Min-Max	Median (middle)
I	129.80	96–160	132	3.97	0.00–6.90	4.00
II	142.80	120–160	140	3.98	0.00–6.40	5.00
III	146.88	132–163	140	4.22	0.00–8.40	5.00
IV	102.33	92–116	102	2.30	0.00–3.90	2.70

The authors conclude, “We demonstrated the decreased diameter of pregnancies with poor outcome and we agree with recent studies that support the negative predictive value of the absence of yolk sac.”

What their numbers show is that the mean (average) yolk sac diameter for the miscarriage group was 2.30mm.  The mean yolk sac diameter for the groups where the pregnancies continued was around 4mm and up.  (The median (middle) measurement for the miscarriage group was 2.70mm.  The median for the groups where the pregnancies continued was almost 4-5.)  Note also that the pregnancy loss group had much lower heart rates.  Mean (average) of 102 versus 130+.  (Median (middle) was similar.)

Sigh.  I’m not feeling good about my 2.5mm yolk sac.

Okay, almost done.  This article suggests that in week 6, yolk sac diameter mean is 2.9mm (min 2mm, max 7.2mm):

http://medultrason.ro/assets/Magazines/NewFolder/04Tan.pdf

That does not make 2.5mm look too bad.  It again concludes that “When compared with pregnancies that had a yolk sac diameter <5 mm, the pregnancies with a yolk sac diameter ≥5 mm had a significantly higher risk of miscarriage.”  There was not much about small yolk sacs.  

This article suggests “Usually the inner diameter of a yolk sac measures 3 to 5 mm”:

http://www.jultrasoundmed.org/content/31/1/87.full

It also has the most detail (but still not a lot) about a small yolk sac:

“Small Yolk Sac

The literature presents scant knowledge about the clinical importance of small yolk sacs. It has been claimed that a very small yolk sac may be a normal finding during early periods of normal embryologic development. On the other hand, a much earlier published study, with certain limitations, suggests that a yolk sac diameter of 2 mm or less may be associated with an adverse outcome in pregnancies with a gestational age of 8 to 12 weeks (Figure 7).14

It is well known that the yolk sac size begins to decrease during the late weeks of the first trimester.1,12 This process is why gestational age should be taken into account when the size of the yolk sac is assessed. However, it would be prudent to perform serial sonographic examinations within a short period whenever a smaller-than-expected yolk sac has been visualized.”

Okay, so a small yolk sac might be okay as long as it’s not below 2mm.  I guess only time will tell if my tiny sac is a problem (potentially caused by my hematoma??!!) or not.

Hoping my embryo’s heart is beating like a hammer

There are lots of articles reporting that lower heartbeats are indicators of a pregnancy that is less likely to be viable.

This is the best article I found, showing the loss rate based on the heartbeat rate (beats per minute) between 4-6 weeks of “embryo age” (EA was defined as gestational age minus 14 days).  In other words, 4-6 weeks of EA is 6-8 weeks “pregnant” (ie from LMP).

http://www.fertstert.org/article/S0015-0282(08)00597-9/pdf

Embryo heartrate (bpm)	Total no. of cases	Overall ongoing pregnancies, n (%)	Pregnancy loss rate <=35 yrs	Pregnancy loss rate >35 yrs
60–110	41	11 (27%)	9 (50%)	21 (91%)
111–120	66	53 (80%)	2 (7%)	11 (29%)
121–130	137	112 (82%)	5 (7%)	20 (28%)
131–140	144	132 (92%)	3 (4%)	10 (14%)
141–150	123	112 (91%)	5 (7%)	6 (11%)
151–160	84	81 (96%)	0 (0%)	3 (7%)
>160	55	54 (98%)	0 (0%)	1 (3 %)

As can be seen, a faster heartrate is always better, and older moms were more likely to lose pregnancies even at higher heartrates.  (The same percent of 35+ moms lost pregnancies at 151-160bpm as did the younger moms at 111-120bpm.)

It also shows the average heartrate for an ongoing pregnancy versus loss by week:

Embryo age (weeks)	Embryo heartrate (bpm) ongoing pregnancy (n = 555)	Embryo heartrate (bpm), pregnancy loss (n = 95)
4 [6 weeks pregnant]	131	123
5 [7 weeks pregnant]	143	118
6 [8 weeks pregnant]	160	109

What’s interesting is that at embryo age 4 weeks (ie. 6 weeks pregnant), the difference in embryo heartrate between the ongoing pregnancies and losses is very small.  By embryo age 6 weeks (ie. 8 weeks pregnant), there’s a noticeable difference. 

Here’s another one showing the correlation between pregnancy loss and slow heartrate:

http://pubs.rsna.org/doi/abs/10.1148/radiol.2362040880

“The heart rate was classified as slow if it was fewer than 90 beats per minute prior to 6.3 weeks or fewer than 110 beats/min at 6.3–7.0 weeks, normal if it was 100 or more beats/min at less than 6.3 weeks or 120 or more beats/min at 6.3–7.0 weeks, or borderline if it was 90–99 beats/min prior to 6.3 weeks or 110–119 beats/min at 6.3–7.0 weeks…. The rates of first-trimester demise were 60.6% for pregnancies with slow heart rates at 6.0–7.0 weeks (188 of 310), 17.4% for those with borderline heart rates (103 of 593), and 9.1% for those with normal heart rates (186 of 2034).”

And another one:

http://www.ncbi.nlm.nih.gov/pubmed/7658510

“Below 6.2 weeks, prognosis improved as heart rate increased to 100 beats per minute, then plateaued for rates > or = 100 beats per minute. At 6.3-7.0 weeks, prognosis improved up to 120 beats per minute, then plateaued. Heart rate norms could not be established at 7.1-8.0 weeks because of the small number of embryonic or fetal deaths in this age group; however, all embryos with heart rates below 110 beats per minute at 7.1-8.0 weeks died. We conclude that the lower limit of normal is 100 beats per minute up to 6.2 weeks' gestation and 120 bpm at 6.3-7.0 weeks”

A slower heartrate is (unsurprisingly) correlated with chromosomal abnormalities:

http://www.jultrasoundmed.org/content/28/5/609.full

This one has a super detailed chart showing gestation days, crown to rump length, embryonic heartrate, gestational sac diameter, and yolk sac diameter. 

http://www.fetalmedicine.com/synced/fmf/2010_27.pdf

Tomorrow I will be 6 weeks 3 days in gestational age.  That’s 45 days.  Here are their numbers for 45 days:

Gestation days	CRL, mm			Embryonic HR, bpm			GSD, mm			YSD, mm
	50th	5th	95th	50th	5th	95th	50th	5th	95th	50th	5th	95th
45	5.4	3.4	7.9	120	104	138	17.4	11.7	24.3	3.6	2.7	4.5

This is another super interesting article.  (Not a medical journal article.)  It shows what events are roughly occurring days after the last period, and ranges of HCG.  Although there is no clear “science” behind these numbers, it made me feel better that at my last appointment there was no heartbeat seen at 5w3d and an HCG over 11,000.  Of course by 6w3day (tomorrow) I better see a heartbeat.

http://www.babymed.com/normal-hcg-levels-pregnancy

Days from last period	Weeks from last period	Days from conception	Events	Mean hCG	Range hCG
26	3w+5d	12		25	0-50
27	3w+6d	13		50	25-100
28	4w+0d	14		75	50-100
29	4w+1d	15		150	100-200
30	4 2/7	16		300	200-400
31	4 3/7	17		700	400-1,000
32	4 4/7	18		1,710	1,050-2,800
33	4 5/7	19		2,320	1,440-3,760
34	4 6/7	20		3,100	1,940-4,980
35	5	21		4,090	2,580-6,530
36	5 1/7	22		5,340	3,400-8,450
37	5 2/7	23		6,880	4,420-10,810
38	5 3/7	24	yolk sac appears	8,770	5,680-13,660
39	5 4/7	25	yolk sac appears	11,040	7,220-17,050
40	5 5/7	26	yolk sac appears	13,730	9,050-21,040
41	5 6/7	27	yolk sac appears	15,300	10,140-23,340
42	6	28	heartbeat appears	16,870	11,230-25,640
43	6 1/7	29	heartbeat appears	20,480	13,750-30,880
44	6 2/7	30	heartbeat appears	24,560	16,650-36,750
45	6 3/7	31	embryo appears	29,110	19,910-43,220
46	6 4/7	32	embryo appears	34,100	25,530-50,210
47	6 5/7	33	embryo appears	39,460	27,470-57,640
48	6 6/7	34	embryo appears	45,120	31,700-65,380
49	7	35		50,970	36,130-73,280
50	7 1/7	36		56,900	40,700-81,150
51	7 2/7	37		62,760	45,300-88,790
52	7 3/7	38		68,390	49,810-95,990
53	7 4/7	39		73,640	54,120-102,540
54	7 5/7	40		78,350	58,200-108,230
55	7 6/7	41		82,370	61,640-112,870
56	8	42		85,560	64,600-116,310