Understanding Obesity During Pregnancy

A pregnant woman measuring her waist
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Pregnancy and weight are something that is often talked about, though most of the discussions tend to center around gaining weight while you are pregnant. Another issue to discuss is what happens to a woman and her pregnancy when she starts pregnancy in the overweight or obese categories. The truth is this is a multifaceted issue, not just medical or weight related.

How Obesity Is Defined in Pregnancy

Obesity is an increasing issue with more and more women beginning pregnancy already in the overweight or obese categories. About forty percent of women are in the overweight category and fifteen percent are considered obese according to the World Health Organization (WHO). Overweight is defined as having a body mass index (BMI) between twenty-five and twenty-nine point nine, while obesity is defined as a BMI above thirty. These are the same definitions that are used prior to pregnancy. The BMI is typically calculated on the pre-pregnancy weight and not the weight gain in pregnancy.

Care in Pregnancy and Beyond

One of the biggest but rarely spoken about issues about pregnancy and weight is how pregnant women of size are treated. We know that in general, patients who are obese or overweight can wind up feeling unsatisfied with their care or feeling like they are not receiving adequate care. This is unacceptable and you should not tolerate being treated poorly because of your weight.

As a pregnant person, you have a right to be treated respectfully and with the care that is appropriate for your pregnancy and/or medical conditions. This includes ensuring that you have adequate medical instruments for your weight—a great example is a well fitting blood pressure cuff. This is instrumental in ensuring that your blood pressure is being measured adequately more examples: scales that weigh you accurately and furniture that fits you, including a labor bed and exam table.

How Obesity Affects Pregnancy

The very first issue that someone may suffer from when trying to get pregnant while being overweight or obese is trouble conceiving. There are certain women who will suffer from issues with polycystic ovarian syndrome (PCOS), which can cause infertility or trouble getting pregnant. There are also some women who simply have a lower fertility rate called subfertility. This is in addition to the potential risks of impaired fertility from the complications of obesity in general, such as high blood pressure and diabetes.

Once pregnant, there are also other potential complications from the increased weight including:

Each of these issues has their own risks associated with them. It can mean that you need to have an increased number of prenatal care visits, that you require medications or closer monitoring. This is one reason why prenatal care is so important and why it is important that it be tailored to you.

Pregnancy Weight Gain 

One thing that is clear, even if you start pregnancy with more weight than your practitioners would like, it is still important to gain weight in pregnancy. A woman in the obese or overweight category will need to gain less weight for a healthy pregnancy, but weight gain is still something that is encouraged.

For women who are overweight, a weight gain of fifteen to twenty-five pounds is recommended, with about two to six and a half pounds being from the first trimester, and about a half pound of weight gain every week in the second and third trimesters. This weight gain increases with twins to be thirty-one to fifty pounds total.

If you are obese at the start of pregnancy, it is recommended that you gain no more than just over four pounds by the end of the first trimester, and gain only about a half pound a week in the second and third trimesters. The goal is to have a weight gain total between eleven and twenty pounds. If you are expecting twins, that number rises to twenty-five to forty-two pounds total.

Losing Weight While Pregnant

It is not recommended that anyone attempt to lose weight in pregnancy. This is true, no matter what your starting weight is. Dieting in pregnancy deprives your baby of needed calories. It is also thought to cause a potential problem with burning maternal fat stores potentially releasing toxins into the body. This is not to say that you should eat whatever you want, a diet that is well rounded and full of hearty foods is much better for your pregnancy and baby than a diet that is high calorie and low quality.

Labor in Obese Women

There are many things that have been said or beliefs that have been held about labor with a woman who is overweight or obese. A recent wave of research has helped us clarify these thoughts and to put them into place within a modern medical context.

You may be at an increased risk in labor for:

Women in these weight categories may have a longer first stage of labor, the part where the cervix is dilating. A practitioner would be advised to provide extra time in this phase of labor and not intervene as long as the mother and baby are doing well.

Epidural anesthesia is possible for women in a higher weight category. Though it may be technically more challenging from the perspective of the anesthesiologist. If you fall into this category, you might want to consider a pre-labor consult with the anesthesia department at your hospital for information that is specific to you. Labor is not when you want a surprise sprung.

The second stage of labor, or pushing, was once thought to be longer for overweight or obese women. Recent research has not found that to be the case. In fact, a small study showed that these women had similar intraabdominal pressures to normal weight counterparts. That said, augmentation with synthetic oxytocin was more common. It is also an important point to note that an increased BMI seems to have a protective effect against having a third or fourth-degree laceration on the perineum.

Induction of Labor and Cesarean Birth

Cesarean section has its own set of issues in overweight and obese women. Though it is important to note that a planned cesarean section for weight alone does not improve the outcomes for baby or mother. The risk for needing a cesarean is not as straightforward as one might assume.

If you begin labor spontaneously, the rates of cesarean section during labor are the same for women of all weight categories. When the risk for cesarean section rises for mothers in the overweight and obese categories is when labor is induced or started artificially. While there are currently studies being done to look at what could be altered to control this rise, there are currently no recommendations for what type of induction would be the most effective.

What we do know is that women who are overweight or obese do have a higher rate of complications that would make an induction of labor the appropriate intervention. What comes next is balancing the risks of prolonging the pregnancy and the risks of induction and potential cesarean birth.
A cesarean birth is technically more challenging from the standpoint of the anesthesia team and the surgeon. This is another time when having adequately sized equipment can be very helpful for both the surgeon and the patient.

Preconception Planning for the Future

One thing that is often recommended is that obesity and weight related issues are addressed prior to pregnancy. However, there have been no real studies on what is effective and what isn’t in terms of which is best. Though what experts do agree on is that when possible you should lose weight, even if it doesn’t completely resolve a weight issue, any weight lost is considered beneficial.

If you are having trouble with losing weight or chose not to wait, then ensuring that you are working to be as healthy as possible. Being overweight or obese can have a detrimental effect on your health, but it is not a promise of complications. Good prenconceptional health screening can identify any potential issues and you can address those prior to getting pregnant. This already can help your future pregnancy be healthier when you are not trying to identify and treat additional issues during pregnancy.

All of that said, there is research that shows that losing weight in between pregnancies can cause basically a yo-yo effect with the weight, potentially even causing a woman to gain more weight during her pregnancy or between her pregnancies. One of the most effective things to do is to deal with weight-related illnesses prior to pregnancy, the high blood pressure, and blood glucose issues, as many of the complications seen in pregnancy come from these issues.

High-Risk Label

Many overweight or obese women find themselves being forced into medical practices that are all high risk, even in absence of chronic problems and being forced to accept interventions or testing that they may not want. This is because the majority of women in the overweight and obese category are often labeled as high-risk patients.

While being overweight or obese may increase some complications, the majority of complications that happen in pregnancies within these weight categories are still because of a chronic condition, which may or may not be related to the weight. A great example would be pre-existing blood pressure problems. Though it is also true that many women don’t understand that being labeled high risk is not the same thing as saying you will absolutely have complications in pregnancy, simply that there is a greater chance of it happening.

Even with the high-risk label, a good number of women should be able to have low intervention pregnancy and births. This largely depends on the practitioner that you chose and their guiding philosophy. As a pregnant person, you do have rights and can exercise them, this can include finding a new practitioner if appropriate.

What to Do If You Feel Like You Are Treated Poorly Because of Your Weight

You should first of all speak up. Your doctor or midwife may not realize that you are feeling bad about your care. This allows you a chance to clear the air. If you aren’t comfortable doing this in person, consider writing a letter to your provider. If your concerns are not addressed in a manner that is to your liking, consider seeking care from another group of physicians.

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