Weight is a sensitive topic, and we understand that many have difficulty discussing it. In the context of family planning, it’s important to talk about it – as maintaining a healthy weight is a key component to bolstering your overall health, as well as your fertility health. For adults and children alike, most doctors agree that excess weight and obesity can increase the likelihood of some health risks such as Type 2 diabetes, high blood pressure, cardiovascular irregularities and stroke. Being underweight can impact your overall health and cause cycle irregularities, making it difficult to conceive- as well as once you do become pregnant, increasing the risk for obstetrical problems such as premature delivery. Being underweight can also increase your risk for later life osteoporosis, cardiovascular problems and stroke.
For individuals who may be trying to conceive, weight management is an especially important consideration, as having excess weight, or not enough weight, can result in hormone dysregulation and higher risk pregnancy.
BMI and fertility
BMI, or Body Mass Index, refers to a ratio of weight and height used to assess body fat percentage and obesity. To understand how BMI affects fertility, it is important to first understand BMI generally, and how some physicians use it as a scale of health:
- Underweight individuals have a BMI of less than 18.5
- Normal weight individuals have a BMI that falls between 18.5 and 24.9
- Overweight individuals have a BMI that falls between 25 and 29.9
- Individuals with obesity have a BMI of 30 or greater
Understanding a patient’s BMI allows providers to assess their risk for certain health conditions such as heart disease, sleep apnea and Type 2 diabetes. For patients trying to get pregnant, providers may use this tool to understand the patient’s overall risk in pregnancy, as well as fertility impacts, such as first trimester miscarriage or ovulatory dysfunction.
There are many factors that can impact an individual’s BMI, like your age, gender, and ethnicity. It is also important to note that there are also other conditions that can impact fertility and weight such as Polycystic Ovarian Syndrome (PCOS) and untreated thyroid disease. These conditions may make it harder to lose or gain weight and reach your optimal BMI. For instance, PCOS makes it difficult for the body to use insulin, and high levels of this hormone can increase the production of male hormones, leading to weight gain.
Weight looks different for each individual and if you have concerns about your BMI and your ability to get pregnant, we recommend speaking to your provider.
Risks of being overweight or underweight in people with ovaries
Ovulatory Dysfunction: Ovulation is the ability to release an egg every month, with the average menstrual cycle length ranging from 21 to 35 days. Cycles falling outside of that range of days could signal ovulatory dysfunction, meaning the hormonal signals from the brain to the ovaries are out of balance; both underweight and overweight can interfere with these hormonal signals:
- Higher estrogen levels: With increased excess weight, women can have higher estrogen levels. This comes from the fact that adipose tissue, or fat tissue, can make estrogen itself. Higher estrogen levels can lead to ovulatory dysfunction.
- Decrease in Gonadotropin-Releasing Hormone (GnRH): If you are underweight, the brain may not produce enough GnRH–the hormone that tells the pituitary gland to release FSH (follicle stimulating hormone) and LH (luteinizing hormone). Without enough of these hormones, ovarian follicles cannot develop, which can lead to irregular or sporadic ovulation, or cessation of ovulation.
High-risk pregnancy: In addition to posing fertility health complications, being underweight or overweight can result in higher risk pregnancies, according to the American College of Obstetricians and Gynecologists (ACOG):
- Underweight individuals are at a higher risk for having babies that are underweight and are at risk for preterm labor and preterm birth.
- Overweight individuals are at an increased risk for first-trimester miscarriage and fetal demise, which is the passing of the infant after 20 weeks-gestation. Excess weight also increases the risk of high blood pressure during pregnancy, which can lead to pre-eclampsia, a condition that can cause serious complications during pregnancy and delivery. Additionally, excess weight is linked to an increased risk for diabetes in pregnancy (gestational diabetes), as well as birth defects; in particular, cardiac defects and neural tube defects. There is also an increased risk of preterm birth.
Risks of excess weight in people with testes
Hormone imbalance: For people with testes, having excess weight can lead to hormone imbalances as well. Obesity elevates body temperatures, specifically around the scrotum, which studies show can result in lower testosterone production and higher estrogen production.
Abnormal sperm production: Abnormal hormones can, in turn, lead to abnormal sperm production, which are associated with irregularities such as low sperm count or motility, which often results in poor fertilization rates.
Nutrition and exercise for weight maintenance
A healthy diet, coupled with exercise, is tremendously important for reproductive health. According to the American Society for Reproductive Medicine, the best foods for fertility include plant-based proteins, whole grains, and a wide variety of fruits and vegetables. Experts also suggest limiting trans fats and opting for monounsaturated fats such as avocado and olive oil. Studies also show that this anti-inflammatory diet is ideal for managing weight and blood sugar. The Mediterranean Diet is often recommended as the best diet to follow when trying to conceive and maintaining a healthy diet and lifestyle.
For help with meal planning and maintaining a healthy diet, many find meeting with a nutritionist or dietician very helpful. It can feel overwhelming to manage your nutrition and talking with an expert can help. For helpful and easy to follow guidelines, check out this government release guide.
In addition to supporting general well-being, exercise is a key factor to keeping weight at healthy levels and is a great lifestyle consideration for those trying to conceive. Experts advise that people with ovaries trying to get pregnant keep their exercise moderate, as intense physical activity may disrupt the menstrual cycle. Consider moving in a gentle form that increases your heart rate – such as jogging or swimming – for thirty minutes per day, four to seven days per week. Please consult with your doctor for individual needs.
It’s also important for people with sperm to implement moderate physical activity, as evidence shows that exercise is related to high sperm quality. Experts most often advise weight resistance and cardiovascular exercises for this community – two forms of movement that can boost testosterone levels.
If you’ve optimized your nutrition and added exercise to your schedule and are having challenges, talk to your doctor who may be able to run tests to help you understand what may be affecting your overall health.
Progyny prioritizes whole-person wellbeing wherever you are on your family building journey, and members have access to ongoing support from Patient Care Advocates (PCAs) who can help provide more education and guidance. Please reach out to your dedicated PCA for additional information, and as always, speak with a provider for treatment consultation. Please note this content is for informational purposes and is not intended as a substitute for medical advice. Please consult with your healthcare provider about your specific journey.