Pregnancy weight gain when underweight - confused

[Roeslein]

So I have always been just on threshold between underweight and normal weight (BMI = 18). I eat healthy, just never had a big appetite, get sick when eating fatty foods and not really into sweets etc. Anyway I was only weighted at the 12 weeks appointment (had already put on 5 kg by then, so was technically normal weight at that point) and when I asked how much I should aim to gain the midwife said I needed to put on 11 kg during the whole pregnancy. I even asked if she meant in addition to my pre-pregnancy weight and she said yes. So I'm 38 weeks tomorrow and have put on exactly 11 kg on top of my pre-pregnancy weight (not on top of the 12 weeks weight). I just had a growth scan yesterday at which my baby measured on the 11th percentile for abdominal circumference. Consultant said he was not concerned as husband and I are quite small so the baby is proportional, but he also said that based on my "real" pre-pregnancy weight I actually should have put on more weight because I should have been in the underweight group? I've been eating healthy, lots of fruit etc. but haven't put on much in the third trimester due to not being hungry / not much space in stomach - most of my gain was in the 1st and 2nd tri. Also taking iron supplements due to a deficiency. Now I am worried I have hurt my baby when I just followed the midwife's advice. Can someone clarify?

Baby takes what it needs and leaves you with the leftovers - which might be why you have become a bit iron deficient? Honestly, it's not an issue in the biological sense (think of women who have babies in times of famine).

Everyone’s weight gain varies in pregnancy. As long as you haven’t been hungry/depriving yourself then it’s fine. The baby will take what it needs.
I am 22 weeks and have only just got back to my pre pregnancy weight due to severe sickness.

This is a very rough guide but I have found it quite useful:
www.babycenter.com/pregnancy-weight-gain-estimator

11kg is quite a small estimate for weight gain. It’s right at the bottom of what you’d expect someone in a healthy weight range to gain so for someone who is borderline/underweight, I would expect that to be higher. But at the end of the day if your baby is growing and you feel well, it isn’t important.

Interesting you say you’ve been ‘following the midwife’s advice’ though. Most women don’t overthink or manage their weight a great deal in pregnancy. Have you been trying not to gain more than 11kg?

Yes, I agree with StarfishSandwich ^. How much have you been trying to control your weight gain throughout the pregnancy?
To be honest I’ve always treated the weight gain guidelines as a rough guide, I’ve just eaten when hungry, mainly eaten healthily with the odd treat (just like i usually eat to be honest).

Yes also interested in how you followed the advice. I have no idea how much I have gained, I haven’t been weighed since my 12 week scan.

Starfish, I have not been "trying to not gain more than 11kg" but I meant more I have been weighing myself every now and then to make sure I was still gaining / not losing weight and thought I was fine given I had gained the required amount?

Well if you are ok and the baby is ok then find something else to worry about, everything is alright!
Best of luck!

I think midwife said it was a good idea to weight yourself every once in a while to make sure you're roughly on track to target weight gain, not way too low or too high so you can course correct if needed? Seems reasonable to me, otherwise how do you know how you are doing?

I was medically underweight both pre pregnancy and throughout. And on paper didn't gain much in pregnancy either.

In reality I was naturally thin, and due to small build combined with being tall bmi isn't reflective of healthy weight. I also started pregnancy with a lot of muscle and little fat, which changed throughout pregnancy. So although my limbs/ bum/ hips went up 1/2 clothes sizes the scales didn't really show it.

Some hcps raised concerns, however others looked at fact, not scales.

Babies don't grow from fat reserves. Provided you are taking ample nourishment to maintain what is a natural healthy weight for you, and additional on top for the baby you're doing everything the baby needs.

It's only a problem when it isn't a natural weight for you and you are restricting what you eat to maintain it.

Maybe the midwife didn't realise you had already gained 5kg so was giving you advice based on your weight at the time? I was slightly underweight before dcs1 and 2 and was definitely told to put on more, the idea is about stores of things like iron as well as fat to get you ready for bfing (especially with hungry dc2 I lose a lot of weight really quickly with feeding, I would have had trouble without more gained in advance) I'm sure you'll be fine in any case, we all have different physiques, but maybe it's a good idea to look at some higher calorie things that are still appealing.
I've often found that in the 3rd trimester I don't feel like cooking but if there's food I'll eat it, can your DH or anyone else do the prep? Avocado or nut butters on toast are high energy and easy, milkshakes and smoothies can also be made high energy without being high in junk. Or if you just want more cake, that's an important 3rd trimester and postnatal food group

Don't get yourself worried. If anyone was worried about your weight they would tell you.

I'm naturally thin and normally just underweight. Was given extra scans due to this in both pregnancies. Was never told to gain weight. Never once was weighed. Also never weighed myself.

Both babies always measured above 50th centile and were average weight when born. 7.1 and 7.6

I also breastfed both. Dd1 for 22 months and dd2 still going at 7 months.

As people have said your body priorities the baby so they get the nutrients from your diet before you.

If anyone was concerned you would know about it. It's not the kind of thing that is glossed over. We have enough to worry and stress over when pregnant without adding to it.

Happy pregnancy xx

I either started or was underweight by my booking appointment due to morning sickness plus very low appetite for three of my pregnancies and each time I got different guidance and very different attitudes throughout. Seriously, I got everything from what felt to me like an overly happy that I was gaining barely the minimum expected to another who pretty much said I mustn't care for my child because of how I struggled to eat and kept having ketones in my urine.

I know it's concerning though it reads to me like it's just a difference of professional opinion rather than likely harm has been done. Starting underweight does carry additional risks but if the consultant is not concerned but just thinks the guidance you were given should be different, I would try not to worry about it.

As you said you are struggling to eat, I would recommend to ease some of your concerns a supplement drink like Meritene which can help cover the nutritional basis when you can't stomach eating or products like this which are easy to add to other foods and give a good boost of healthy fats and proteins without much change to flavour or added pressure on the stomach.