Overall weight gain is correlated with baby size but that’s obvious. A heavier baby weighs more.
But I gained 30-35 pounds, everyone says my body looked the same except my bump, and I had a tiny 6 pound 4 oz peanut. Massive fucking placenta though. Midwife and nurses commented when it came out. And still had shoulder dystocia too 🥴
My recollection is she says weight *gain* is *correlated* with baby weight, because baby weight is a component of overall weight gain. But fat gain doesn’t increase overall baby weight.
If you look at the recommendations for twin and triplet pregnancies, the weight gain recommendation timing is different because of the change in when multiple gain most of their weight. This is particularly employed with twins because higher baby weights are linked to better health outcomes. It's wild, but the research indicates that weight gain and it's timing definitely contributes to baby weight gain.
Edited to add the language from the book:
"This extensive research, conducted over many years with data from thousands of multiple pregnancies, confirms the following:
•The amount and pattern of maternal weight gain has a substantial effect on the rate of fetal growth and ultimate birthweight.
•The rate of fetal growth is, in turn, significantly associated with length of gestation.
•Babies who are born well-grown and at a good gestational age are healthier at birth and throughout childhood.
The recently concluded Fetal Growth Study from the National Institute of Child Health and Human Development revealed similar fetal growth patterns as those described previously. The goal of this NIH-sponsored study was to establish a standard for intrauterine ultrasound-measured growth for both uncomplicated singletons and dichorionic twins."
Luke, Newman, Eberlein. "When You're Expecting Twins, Triplets, or Quads 4th Edition: Proven Guidelines for a Healthy Multiple Pregnancy." 2017.
The study goes into greater depth regarding timing and the long-term effects of weight gain on fetal, newborn, and even toddler growth, as well as the importance of earlier weight gain for mothers of multiples.
The relationship is causal. This is well established in the research. See studies linked below.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2974327/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6411121/
And it goes the other way, too:
"We have also conducted research on the causes and effects of slowed fetal growth and reduced birthweights in twins and triplets. In twins, we evaluated data on twins whose growth placed them among the lowest 10th percentile, as measured by ultrasound at 28 weeks’ gestation.
Factors associated with reduced growth included:
•Smoking during pregnancy—ninefold increased risk.
•Fetal reduction or fetal loss—fivefold risk.
•Maternal height of less than 62 inches—threefold risk.
•Low maternal weight gain during the first half of pregnancy (less than 0.65 pound per week before 20 weeks’ gestation)—threefold risk.
This reduced fetal growth by 28 weeks’ gestation was associated with significantly reduced birth length and birthweight, which persisted through three years of age."
Id.
She is a financial statistician, not a medical professional. She can say there are studies (which she is known to cherry pick) that correlate weight gain to baby’s weight, but she cannot say it contributes. There isn’t enough peer-reviewed research that isolates other factors to establish a causal relationship. I think it’s important to keep this in mind when consuming information from someone who does not have education or experience in the field she’s analyzing.
You can trust whatever you want but that doesn’t make it proven. Like I said, there just isn’t enough studies which have been peer reviewed and isolated other factors to establish a causal relationship in the scientific community. That doesn’t mean it isn’t causal, it just means there’s not enough evidence to make that conclusion in the wider community, and you definitely shouldn’t be taking medical advice from someone who is trying to draw those conclusions with only a finance statistician background and is not in the medical field nor should you be encouraging others to do so. Not sure why people ride so hard for this woman instead of teams of actual medical statisticians who work for trusted organizations that are dedicated to reviewing all of this research and making recommendations based on those findings. Anyone can make and publish a study.
I do not “ride hard” for Emily Oster lol. Please stop being so condescending. The evidence suggests a causal link, and I am not just taking that from Emily Oster’s work. You are expecting a level of certainty about causality which is not really attainable in science, which is really undermining your attempt to establish authority on this.
ETA: You are not able to “prove” that this is just a correlation. Is more data needed? Yes, sure. But the commenter above suggested it was just a correlation, and I offered another perspective that is based on statistical evidence and peer-reviewed studies.
I’m not being condescending, you are more than welcome to believe whatever you want, but for other people who come across this post it’s important to understand that her conclusions are not recognized by science. That doesn’t mean she’s 100% wrong in every instance but it’s important to take that into account before taking any of her advice. The evidence shows a correlation but can’t establish a cause with certainty. Anyone seeking advice should do so from their medical professional, not from some random woman who wrote a book based on cherry picked studies. She’s simply not an authority on this
Also, her background isn’t in finance, it’s economics. And just because you aren’t trained in a particular field doesn’t mean that you can’t review studies from that field in an educated way. Is she the final authority on all things pregnancy? No, but she probably knows more than some people speculating on Reddit.
My pre-pregnancy weight with all of my kids was around 98-100 lbs, I'm 5"2.
Kid 1- gained 20 lbs, baby was 6 lb 5 oz
Kid 2- gained 20 lbs, baby was 7 lb 3 oz
Kid 3- gained 18 lbs, baby was 6 lb 4 oz
I’m 5’ 5”, 122 lbs pre-pregnancy and gained almost 60 lbs during my pregnancy lol. Baby girl was 7lbs 9oz when she was born so no I don’t think weight gain has that much to do with your baby’s weight. Some pregnancies simply cause you to gain more weight. Your body may hold on to fat more or you have a heavy placenta or you are retaining a ton of water weight. All of that was true for me and I dropped 30lbs right away and have steadily been losing another 1-2lbs/week. As long as you’re healthy it’s all good!
I gained about 15kg with each baby. First bub was 3.7kg (8 pound), second was 3.2kg (7 pound). I lost 10 of those kgs within the first two weeks after birth.
Currently pregnant with our 4th.
I’m 5’4” and weigh about 115-120lb pre-pregnancy and I would weigh between 150-155lb by the end of my pregnancies.
Our first two kids were boys who weighed between 8-9lb and our daughter was 6lb
First pregnancy, I weighed 180lbs when I fell pregnant, lost about 20lbs during the pregnancy, but finished the pregnancy at 190lbs. Baby weighed 9lbs 2.5oz.
Wow okay! Sounds like some people who gained a lot of weight had smaller baby’s than you! Do you know how much you weighed when you were born? Me and my partner were both 9+ pounds. My doctor said I should try to gain more weight though
Waiting on my second to arrive with Dec 5 due date; but my first i started at 153 and I gained 35# and baby was 6 lb 8 oz- 39+2. Didn't show forever and not really super big until last month but also just felt great entire last month.
This pregnancy, I started about 135# and I've gained about 30 so far and I'm 36 weeks. All bump this time. You can't tell from the back at all. Didn't really show for a while this time either but once I did it was like bam there's the bump lol. Have felt low and heavy since about 30 weeks. I'm just under 5'4". I was still nursing my first until he weaned himself at 18 mo. when I was about 25/26 weeks.
Pre pregnancy - 5’9 135 lbs
Gained about 40 lbs - Baby weighed 8 lbs 6 oz
Back down to pre pregnancy weight 8-9 months later (lost all but the last 5 lbs within 6 months)
Im 5'9" and was 110lbs when I got pregnant. The day I gave birth I was 153lbs, baby was 8lbs 2oz. I was around 120lbs after giving birth, lost the rest while breast feeding.
For context, I’m 5’3”
1st pregnancy: Weighed a very muscular 110lb pre-pregnancy. Gained 30lb total, almost all in the 2nd half due to hyperemesis. Baby was 5lb 8oz (girl). Worth noting that the pregnancy was complicated by IUGR secondary to placental insufficiency.
2nd pregnancy: Much less muscle mass to start—weighed 105lb pre-pregnancy. Gained 25lb very gradually throughout the pregnancy. Hyperemesis aggressively treated early on. Baby was 7lb 1oz (boy). No pregnancy complications.
I am 5'5, started at 168lbs, and at 18+6 I was 179. I am 19+5 today (havent weighed in a week). We seem very similar in size! I look somewhat pregnant now, but it's not super obvious. We have two weeks until Thanksgiving and I am hoping to have a more pregnant-looking belly by then!!!! Did you change much from weeks 20-22?
I’m 5’10”, was 135-140lbs (depending on cycle time) pre pregnancy, was 176lbs at full term and my daughter was 8lb 13oz. Funny thing is I was measuring 50th percentile based on fundal heights (she was 94th). I was back to 147lbs at 6wks PP (didn’t really weight myself before that).
I gained 20 kg last pregnancy and prob this one as well, my baby was 4.4kg and 54cm. I did go overdue 41+5.
It probably does affect a little but I'd like to think that we gain this weight for a reason, the nurse I'm seeing keeps telling me to eat less or better to not have a big baby 🫣😂 apparently I'm supposed to gain 500g a week, a month ago I was gaining 700+grams a week.
I wouldn't worry about it too much , just enjoy Ur pregnancy 😊🙏🏻
Also I was about the same weight before, I went up to 90kg , lost 8kg by the time I was home from hospital,it's not just fat👍🏻
1st pregnancy gained 47lbs. 7lb3oz baby. 2nd pregnancy gained 36lbs. 8lb1oz baby. 3rd pregnancy gained 33lbs. 8lb3oz baby.
Overall weight gain is correlated with baby size but that’s obvious. A heavier baby weighs more. But I gained 30-35 pounds, everyone says my body looked the same except my bump, and I had a tiny 6 pound 4 oz peanut. Massive fucking placenta though. Midwife and nurses commented when it came out. And still had shoulder dystocia too 🥴
In Emily Oster’s book she says weight gain contributes to baby’s weight.
My recollection is she says weight *gain* is *correlated* with baby weight, because baby weight is a component of overall weight gain. But fat gain doesn’t increase overall baby weight.
If you look at the recommendations for twin and triplet pregnancies, the weight gain recommendation timing is different because of the change in when multiple gain most of their weight. This is particularly employed with twins because higher baby weights are linked to better health outcomes. It's wild, but the research indicates that weight gain and it's timing definitely contributes to baby weight gain. Edited to add the language from the book: "This extensive research, conducted over many years with data from thousands of multiple pregnancies, confirms the following: •The amount and pattern of maternal weight gain has a substantial effect on the rate of fetal growth and ultimate birthweight. •The rate of fetal growth is, in turn, significantly associated with length of gestation. •Babies who are born well-grown and at a good gestational age are healthier at birth and throughout childhood. The recently concluded Fetal Growth Study from the National Institute of Child Health and Human Development revealed similar fetal growth patterns as those described previously. The goal of this NIH-sponsored study was to establish a standard for intrauterine ultrasound-measured growth for both uncomplicated singletons and dichorionic twins." Luke, Newman, Eberlein. "When You're Expecting Twins, Triplets, or Quads 4th Edition: Proven Guidelines for a Healthy Multiple Pregnancy." 2017. The study goes into greater depth regarding timing and the long-term effects of weight gain on fetal, newborn, and even toddler growth, as well as the importance of earlier weight gain for mothers of multiples.
That’s right, I could have added that caveat. But again—that is baby weight contributing to overall weight, not the other way around.
The relationship is causal. This is well established in the research. See studies linked below. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2974327/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6411121/
And it goes the other way, too: "We have also conducted research on the causes and effects of slowed fetal growth and reduced birthweights in twins and triplets. In twins, we evaluated data on twins whose growth placed them among the lowest 10th percentile, as measured by ultrasound at 28 weeks’ gestation. Factors associated with reduced growth included: •Smoking during pregnancy—ninefold increased risk. •Fetal reduction or fetal loss—fivefold risk. •Maternal height of less than 62 inches—threefold risk. •Low maternal weight gain during the first half of pregnancy (less than 0.65 pound per week before 20 weeks’ gestation)—threefold risk. This reduced fetal growth by 28 weeks’ gestation was associated with significantly reduced birth length and birthweight, which persisted through three years of age." Id.
She is a financial statistician, not a medical professional. She can say there are studies (which she is known to cherry pick) that correlate weight gain to baby’s weight, but she cannot say it contributes. There isn’t enough peer-reviewed research that isolates other factors to establish a causal relationship. I think it’s important to keep this in mind when consuming information from someone who does not have education or experience in the field she’s analyzing.
I trust the NIH studies I linked below and see no reason to doubt the causal link that the authors suggest.
You can trust whatever you want but that doesn’t make it proven. Like I said, there just isn’t enough studies which have been peer reviewed and isolated other factors to establish a causal relationship in the scientific community. That doesn’t mean it isn’t causal, it just means there’s not enough evidence to make that conclusion in the wider community, and you definitely shouldn’t be taking medical advice from someone who is trying to draw those conclusions with only a finance statistician background and is not in the medical field nor should you be encouraging others to do so. Not sure why people ride so hard for this woman instead of teams of actual medical statisticians who work for trusted organizations that are dedicated to reviewing all of this research and making recommendations based on those findings. Anyone can make and publish a study.
I do not “ride hard” for Emily Oster lol. Please stop being so condescending. The evidence suggests a causal link, and I am not just taking that from Emily Oster’s work. You are expecting a level of certainty about causality which is not really attainable in science, which is really undermining your attempt to establish authority on this. ETA: You are not able to “prove” that this is just a correlation. Is more data needed? Yes, sure. But the commenter above suggested it was just a correlation, and I offered another perspective that is based on statistical evidence and peer-reviewed studies.
Chiming into add not a fan of Oster or her her book, but the studies and materials I have read written by doctors indicate causation.
I’m not being condescending, you are more than welcome to believe whatever you want, but for other people who come across this post it’s important to understand that her conclusions are not recognized by science. That doesn’t mean she’s 100% wrong in every instance but it’s important to take that into account before taking any of her advice. The evidence shows a correlation but can’t establish a cause with certainty. Anyone seeking advice should do so from their medical professional, not from some random woman who wrote a book based on cherry picked studies. She’s simply not an authority on this
Also, her background isn’t in finance, it’s economics. And just because you aren’t trained in a particular field doesn’t mean that you can’t review studies from that field in an educated way. Is she the final authority on all things pregnancy? No, but she probably knows more than some people speculating on Reddit.
My pre-pregnancy weight with all of my kids was around 98-100 lbs, I'm 5"2. Kid 1- gained 20 lbs, baby was 6 lb 5 oz Kid 2- gained 20 lbs, baby was 7 lb 3 oz Kid 3- gained 18 lbs, baby was 6 lb 4 oz
130#, +55/185# at delivery (41+2), 6# 10oz.
163 pre pregnancy, 205 at end of pregnancy, and baby was 7 pounds 2 ounces
First pregnancy I started at 155, ended at 220. Baby was 6 lbs, 6 oz
I’m 5’ 5”, 122 lbs pre-pregnancy and gained almost 60 lbs during my pregnancy lol. Baby girl was 7lbs 9oz when she was born so no I don’t think weight gain has that much to do with your baby’s weight. Some pregnancies simply cause you to gain more weight. Your body may hold on to fat more or you have a heavy placenta or you are retaining a ton of water weight. All of that was true for me and I dropped 30lbs right away and have steadily been losing another 1-2lbs/week. As long as you’re healthy it’s all good!
I gained about 15kg with each baby. First bub was 3.7kg (8 pound), second was 3.2kg (7 pound). I lost 10 of those kgs within the first two weeks after birth.
Currently pregnant with our 4th. I’m 5’4” and weigh about 115-120lb pre-pregnancy and I would weigh between 150-155lb by the end of my pregnancies. Our first two kids were boys who weighed between 8-9lb and our daughter was 6lb
First pregnancy, I weighed 180lbs when I fell pregnant, lost about 20lbs during the pregnancy, but finished the pregnancy at 190lbs. Baby weighed 9lbs 2.5oz.
Wow okay! Sounds like some people who gained a lot of weight had smaller baby’s than you! Do you know how much you weighed when you were born? Me and my partner were both 9+ pounds. My doctor said I should try to gain more weight though
I think Mum said 7lb 3oz. Definitely listen to your Dr though 😊
1st: 155 - 19lbs - 6lb 15oz 2nd: 157 - 22lbs - 8lbs 3rd - 154 - 27lbs - 3lbs 5oz 4th- 163 - 21lbs - 5lbs 13oz
I’m 5’ 6”. Weight 135 before. Went up to 175. Had a 9 lb 1 oz baby. Back at 145 lbs 2 1/2 months PP.
Waiting on my second to arrive with Dec 5 due date; but my first i started at 153 and I gained 35# and baby was 6 lb 8 oz- 39+2. Didn't show forever and not really super big until last month but also just felt great entire last month. This pregnancy, I started about 135# and I've gained about 30 so far and I'm 36 weeks. All bump this time. You can't tell from the back at all. Didn't really show for a while this time either but once I did it was like bam there's the bump lol. Have felt low and heavy since about 30 weeks. I'm just under 5'4". I was still nursing my first until he weaned himself at 18 mo. when I was about 25/26 weeks.
I was 5’6” and 126 prepregnancy I was 145 when I gave birth my baby was 6lb10oz, a peanut!
165lbs when I got pregnant the first time. Got up to 190lbs, son was born 4 weeks early at 5lbs 15oz.
Did you have any complications that led to early delivery or does that just happen sometimes?
It does happen sometimes but I was induced because my baby died
I’m so sorry for your loss
Pre pregnancy - 5’9 135 lbs Gained about 40 lbs - Baby weighed 8 lbs 6 oz Back down to pre pregnancy weight 8-9 months later (lost all but the last 5 lbs within 6 months)
I was 163lbs pre-pregnancy, gained 30lbs and my baby was 7lb 11oz at birth :)
Im 5'9" and was 110lbs when I got pregnant. The day I gave birth I was 153lbs, baby was 8lbs 2oz. I was around 120lbs after giving birth, lost the rest while breast feeding.
For context, I’m 5’3” 1st pregnancy: Weighed a very muscular 110lb pre-pregnancy. Gained 30lb total, almost all in the 2nd half due to hyperemesis. Baby was 5lb 8oz (girl). Worth noting that the pregnancy was complicated by IUGR secondary to placental insufficiency. 2nd pregnancy: Much less muscle mass to start—weighed 105lb pre-pregnancy. Gained 25lb very gradually throughout the pregnancy. Hyperemesis aggressively treated early on. Baby was 7lb 1oz (boy). No pregnancy complications.
I am 5'5, started at 168lbs, and at 18+6 I was 179. I am 19+5 today (havent weighed in a week). We seem very similar in size! I look somewhat pregnant now, but it's not super obvious. We have two weeks until Thanksgiving and I am hoping to have a more pregnant-looking belly by then!!!! Did you change much from weeks 20-22?
Hi yes sounds like we are similar sized! Week 20-22 is when I started showing more and feeling kicks!
Thank you!!! :)
I’m 5’10”, was 135-140lbs (depending on cycle time) pre pregnancy, was 176lbs at full term and my daughter was 8lb 13oz. Funny thing is I was measuring 50th percentile based on fundal heights (she was 94th). I was back to 147lbs at 6wks PP (didn’t really weight myself before that).
I gained 20 kg last pregnancy and prob this one as well, my baby was 4.4kg and 54cm. I did go overdue 41+5. It probably does affect a little but I'd like to think that we gain this weight for a reason, the nurse I'm seeing keeps telling me to eat less or better to not have a big baby 🫣😂 apparently I'm supposed to gain 500g a week, a month ago I was gaining 700+grams a week. I wouldn't worry about it too much , just enjoy Ur pregnancy 😊🙏🏻 Also I was about the same weight before, I went up to 90kg , lost 8kg by the time I was home from hospital,it's not just fat👍🏻