Low blood sugars during second trimester?

I have been type 1 diabetic for 24 years. I am 30 and am 20 weeks pregnant on the second pregnancy. Sadly our first pregnancy resulted in a stillbirth and our son Anthony died at 35 weeks of pregnancy. 10 weeks after the stillbirth and I became pregnant again and am now 20 weeks.
The doctors were unable to give us a reason why the first still birth happened. The only noticeable thing with our baby after the autopsy was that he was big (9 pounds at 35 weeks).
Now at 20 weeks pregnancy with our little girl, I have noticed with the endo and obyn that my insulin demand has not increased as it should normally in a pregnancy but rather has been decreasing even as recent as week 19. The doctors said that this could be because of a problem with the hormones from the placenta and if this trend of not needing to increase the insulin continues, then there is a high chance that the baby would need to be prematurely born after taking some steroids to help the lungs. They did say it is still too early to tell and no blood test or ultrasound can identify this problem but it can cause premature birth(34 weeks was their estimate).
Has anyone experienced a decrease in insulin needs during mid pregnancy or have any experience with a similar situation. We are looking for any type of knowledge on this.
Thank you,

Hi there,

I'm so sorry to hear of your loss.

I am 22 weeks pregnant with my second. I did not have second trimester lows but I did in the last trimester during my first pregnancy.

I was told that lows in the third trimester are a sign of poor placental health. My son was born 1 month premature and the placenta was found to be very calcified.

If you're in Canada I would contact the following clinic in Toronto:


This is a world renowned placenta obstetrician and they can take a closer look at the placenta via a specialied ultrasound.

I just went to the clinic last week, it's remarkable.

If you are in another country, try googling a similar specialist. I'd really demand seeing someone with a high specialty in this area. You could even email/call Dr. Kingdom, here in Canada and see what his opinion would be, as to what you should do.

I've emailed specialists in the US before and received quick replies.

Another suggestion would be to see a doctor who specilizes in bio-identical hormones. Here is what I do (they are wonderful and track your hormones in pregnancy):


Here is a potentially relavant section of the page above:

However, a decrease in progesterone production, presumably by the placenta, during the second and third trimester of pregnancy in a variety of different pregnancy-related complications and previous pregnancy historical events was also observed.

This suggests that the role of progesterone as an indication of placental function may be more significant than what had been previously appreciated and is especially important into the second and third trimesters of pregnancy. This stage of pregnancy has only been minimally studied in the past. While it is not new that a variety of pregnancy-related complications are associated with decreased progesterone production, in the study conducted at the Pope Paul VI Institute, there was an expanded evaluation of that very type of assessment.

For example, it has been shown previously that serum progesterone levels have been noted to be decreased in intrauterine death, premature labor, threatened premature labor, premature rupture of the membranes, amnionitis and abruption of the placenta. Increased levels of progesterone have also been observed in twin pregnancies, Rh isoimmunization and hydatidiform mole. The last two conditions were not a component of the study at the Pope Paul VI Institute.

I've been found to have low progesterone in this pregnancy and definitely believe, as it says above, that it contibutes to placental health.

Sorry for the long reply. I don't want to overwhelm you. I'm praying for the best outcome for you and your baby.

All the best,

Melissa Shannon

Thanks for the reply, what you mentioned about the placenta is very interesting. However, according to all the tests that they conducted on me and my baby, the placenta was fine but I will ask my doctor just to be sure. The endocrinologist is concerned with the little amount of insulin that I am taking and the fact that I am decreasing my insulin doses and not increasing it. Also, the doctors said that there was no way in verifying if my placenta was affected or is being affected by this phenomenon so as a precaution they are talking about inducing me at 34 weeks. I'm still pretty early in my pregnancy so hopefully as things progress they will be able to tell me more.

I appreciate your response and I will be looking into the info you sent.


Melissa Thibault

I'm sorry to hear about the loss of Anthony.

In both of my pregnancies, my insulin needs decreased from week 9 until week 20 and then they turned around. I am now 21 weeks in my second pregnancy. My doctor was surprised by the continued low insulin needs. I am still taking about 2/3 of my pre-pregnancy insulin levels, but that indeed should change in the coming weeks.

I just wanted to let you know that my insulin needs did not increase until later and we are all a bit different in this.

Thanks for the info, my insulin requirements also increased especially in my third trimester. Hopefully everything will be ok this time around.

Thanks again