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From North Carolina, USA:

I am 29 years old and have had Type 1 diabetes for approximately 8 years. I have recently (within the past 4-6 months) changed from Humulin R to Humalog. I also use Humulin NPH. I have been trying to maintain strict control of my sugar levels due to anticipated pregnancy, but seem to be having trouble with random fluctuations. If my blood sugar is within the normal range in the early A.M. (fasting) and remains below 150 in the mid-morning, my blood sugar before lunch is pretty low -- between 35 and 60. If my blood sugar is high in the early-morning, and I fail to take enough Humalog to compensate (e.g., a mid-morning b.s. of 225-265), my blood sugar before lunch is closer to normal (e.g., 65-150). My fluctuations are frequent and cannot always be explained.

Is this normal? Should I be very concerned since I am attempting to get pregnant? My last hemoglobin A1C -- 3 months ago -- was 6.5. Is the Humalog contributing to my frequent mid-morning highs, and if so, should I switch back to Humulin R? How can I maintain blood sugar levels within the normal range in the mid-morning, without having low blood sugar levels at lunchtime? Finally, are the low blood sugar levels in the 30's and 40's dangerous for an unborn baby (pre-conception or post-conception)?

My husband says that I need to see a doctor who knows what he is talking about and I have tried to explain to him that the low blood sugar is a result of my strict control. My main concern is the frequent fluctuations with high blood sugar levels.


Your husband is correct that you should be working closely with a physician experienced in the management of diabetes both before and during pregnancy. You should try to obtain the best possible control before becoming pregnant. You should anticipate that after you become pregnant, you will have to frequently readjust your insulin dose to maintain the best possible control during the pregnancy. Often insulin requirements decrease during the first trimester and may dramatically increase during the second and third trimester.

Severe, unexpected low blood sugars can occur during the first trimester if you are not on the look out for them. You should always be prepared for an unexpected low blood sugar with a very quick acting source of sugar such as cake decorating gel. Keep in mind, that if you have nausea and vomiting during the first trimester, the sugar you take to treat a low blood sugar may take longer than usual to work. Old fashioned coke syrup (the syrup which is mixed with carbonated water to make coca cola - available in restaurant supply stores) works very quickly, is very concentrated so you only need a small amount, and used to be used to treat upset stomachs.

It is unlikely that a few mild low blood sugars have any adverse affect either on the mother or the developing fetus, though studies are still being done to confirm this. The source of "food" for the fetus is the sugar in the mother's blood. If the sugar is low in the mother's blood, the fetus will get less sugar than normal.

If however, the pregnant mother has a low blood sugar and gets into an accident and hurts herself, obviously this isn't good for either the pregnant mother or the fetus, so you should be on the lookout for low blood sugars, so you can treat them quickly. Some lows are bound to occur during pregnancy when you are aiming for strict control. High blood sugars definitely can increase the risk of problems occurring in the baby, so you must aim for strict control. Again, keep in mind, that some high blood sugars will occur. Insulin requirements may double or triple during the course of the pregnancy. The only way you will know you need to increase your insulin dose is to see some high blood sugars. If you are testing frequently, you will be able to adjust the insulin dose as necessary to quickly bring the blood sugar down into the normal range.

Studies with lispro insulin [Humalog®] in pregnancy have just begun so I can't give you any definite advice or facts. I will, however, give you my thoughts regarding what may occur based on what is known about Humalog. If on Humalog you are having problems with blood sugars being lower a few hours after you eat and then going higher before the next meal, this might be more of a problem during pregnancy if you have morning sickness and your food is absorbed and digested more slowly than when you are not pregnant. On the other hand, Humalog may help you get your blood sugar down faster and avoid highs after eating better than Regular. I suggest you first work with you physician to decide what insulin regimen works the best for you before you get pregnant.

If you are having problems with blood sugars going too low a few hours after eating, then increasing a few hours later, you may have to decrease the amount of NPH you are taking in the morning. Alternatively, you might want to take part of your "fast" acting insulin as Humalog and part of your "fast" acting insulin as Regular. If you are considering becoming pregnant, you might want to consider a more intensive regimen with "fast" acting insulin(s) 3 times a day before each meal along with NPH or Ultralente once or twice a day. You may also want to consider using an insulin pump. You should be working with your physician and diabetes team (including the nutritionist) now, before you get pregnant, to decide what works best for you, and to know more about the changes that may occur once you become pregnant.

I wish you and your husband all the best during this exciting time in your lives!


Original posting 7 Jul 97


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Last Updated: Tuesday April 06, 2010 15:08:54
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